The present Invention relates to a method for control of operation of a combustion engine of a vehicle. The invention relates also to a computer programme comprising programme code for a computer for implementing a method according to the invention. The invention relates also to a device for control of operation of a combustion engine of a vehicle and to a motor vehicle, e.g. a hybrid vehicle, which is equipped with the device.

BACKGROUND

Certain motor vehicles are equipped with functionality for saving fuel and reducing emissions by switching off and starting a combustion engine on the occasion of temporarily halts, as when idling at a traffic signal, e.g. a red light, or when loading or unloading freight. Said functionality may be called start/stop functionality or s/s functionality. An example of such vehicles is cars with so-called hybrid drive. Vehicles without hybrid drive may also be equipped with said start/stop functionality. The propulsion of vehicles with hybrid drive may be by means of a combustion engine or a hybrid system comprising an electrical machine and an energy store, e.g. a suitable battery.

During operation of vehicles with said start/stop functionality, said engine will be switched off and started more frequently than during operation of vehicles which are not equipped with said start/stop functionality. This entails greater risk of the vehicle going into unknown or undesirable malfunction modes which might adversely affect the operation of its systems, e.g. the control of various dampers and ancillaries, the operation of adaptations of various systems, the heat regulation of various components or the operation of various sensors and the like. In certain cases various malfunction codes may be generated.

There is at present no user-friendly and effective way for an operator, e.g. at a workshop or service station, to carry out diagnosis of the vehicle on the basis of said malfunction codes generated during the operation of start/stop functionality. According to prior art, an operator is severely limited in his/her scope for diagnosis of the vehicle, as in troubleshooting of malfunction modes relating to start/stop functionality. An operator may thus be forced to switch off or start the vehicle manually by means of a key, in certain cases where a cab of the vehicle is tilted, e.g. to listen for air leakage, inspect a damper of the vehicle or look visually for liquid leakage.

SUMMARY OF THE INVENTION

There is therefore a need to make it easier for an operator to investigate vehicles, e.g. at a service station. There is in particular a need to make it easier for an operator, e.g. during servicing, to investigate malfunctions of ancillaries, components, systems etc. or malfunction codes relating to start/stop functionality of vehicles such as trucks.

One object of the present invention is to propose a novel and advantageous method for control of operation of a combustion engine of a vehicle. Another object of the invention is to propose a novel and advantageous device and a novel and advantageous computer programme for control of operation of a combustion engine of a vehicle.

A further object of the invention is to propose a method, a device and a computer programme for controlling the operation of a combustion engine of a vehicle in a user-friendly and time-effective way during diagnosis of malfunctions relating to start/stop functionality. A further object of the invention is to propose a method, a device and a computer programme for controlling the operation of a combustion engine of a vehicle in a user-friendly and cost-effective way during diagnosis of malfunctions relating to start/stop functionality.

A further object of the invention is to propose a method, a device and a computer programme for conducting effective investigation and/or diagnosis of a motor vehicle.

These objects are achieved with a method for control of operation of a combustion engine of a vehicle according to claim 1 .

One aspect of the invention proposes a method for control of operation of a combustion engine of a vehicle, which vehicle has functions of starting and switching off said engine both via ignition switch and via a start and stop arrangement for temporarily switching said engine off with a view to saving fuel during routine driving. The method comprises the step of

- controlling at least said start and stop arrangement under operator supervision during functional testing of the vehicle.

The result is a user-friendly method whereby an operator can actively determine manually when starting and/or switching off of a combustion engine of a vehicle should take place. This may with advantage be achieved by wireless communication by means of a handheld electronic unit at a distance from a cab of the vehicle. The result in one aspect of the invention is a method whereby said operator has more control of the operation of the engine, e.g. during functional investigation relating to start/stop functionality. It should be noted than when said engine is switched off by means of said start/stop functionality the vehicle may still be in operation, i.e. various systems may be energised and running. In cases where the vehicle has a hybrid system, the latter may continue to be active while said engine is not. One aspect of the invention proposes a workshop test comprising control of operation of a combustion engine of a vehicle, which vehicle has functions of starting and switching off said engine both via ignition switch and via a start and stop arrangement for temporarily switching said engine off with a view to saving fuel during routine driving. The workshop test comprises the step of

- controlling at least said start and stop arrangement under operator supervision during functional testing of the vehicle. The result is a method for easier troubleshooting on a vehicle which has start/stop functionality. This may comprise determining manually when switching off and starting of the engine by start/stop functionality should take place. The method may further comprise the step of

- controlling both said start and stop arrangement and the function of starting and switching off said engine via ignition switch under operator supervision. Said control of starting and switching off said engine may be achieved electronically, e.g. by means of a virtual key.

The result is a versatile method whereby it is possible to conduct not only starting and switching off of the vehicle's engine by means of said start and stop arrangement but also its ordinary starting and/or switching off. This may be achieved by said handheld electronic unit serving as a virtual key for an ignition switch of the vehicle.

The method may further comprise the step

- during said control under operator supervision, of overriding at least certain existing predetermined conditions for allowing starting and/or switching off of said engine. The advantageous result is a method which is user-friendly for said operator. By overriding at least certain non-critical conditions it is possible for said starting and switching off of said engine to be conducted without limitations in the form of substantially unnecessary or unwanted unfulfilled predetermined conditions. A further result is the possibility of carrying out desired servicing or functional testing of said vehicle in a time-effective way.

The method may further comprise the step

- during said control under operator supervision, of adding further predetermined conditions to existing predetermined conditions for allowing starting and/or switching off of said engine.

An effective and safe method according to the present invention may thus be achieved. Said added further predetermined conditions may be safety- related. One example of such a safety-related condition might be that a handbrake or parking brake of the vehicle be activated before said switching off or starting of the engine. Another example might be that a prevailing temperature of a fluid in a certain system be below a predetermined temperature to prevent risk of said operator suffering burns during said functional testing.

The method may further comprise the step of

- controlling said start and stop arrangement for temporary switching off both in the form of discrete starts and stops and in the form of starts and stops according to a predetermined sequence. A discrete start thus represents a distinct event. A discrete stop likewise represents a distinct event. Discrete stops and starts in said sequence may be chosen independently of one another in one embodiment example. The result is a versatile and user-friendly method according to the invention which enables an operator to demand beforehand a predetermined sequence of starts and stops, e.g. at intervals of 2, 5 or 10 minutes. In one example a sequence may comprise a number of starts and switch-offs of said engine where the period of time between said starts and switch-offs may vary. Said sequence may be aligned with a certain checklist for said servicing or functional testing of said vehicle.

The method may further comprise the step of

- controlling said functions by means of an external operator device which may be a portable computer. The method may comprise the step of connecting said externa! operator device for wireless communication to a control unit of said vehicle in order to manage said start and stop functionality. The result is a user-friend!y method according to one aspect of the present invention.

The method may further comprise the step of

- controlling said functions by means of operator devices internal to the vehicle. The advantageous result is an alternative way of implementing an operator-controlled method according to the invention.

The method may further comprise the step

- during said control under operator supervision, of adapting functions relating to starting and/or switching off said engine to said control. This may for example entail predetermined control actions relating to switching off or starting said engine being inactivated. Control actions relating to switching off or starting said engine which do not normally relate to start/stop functionality may also be added and effected. The result is a versatile and user-friendly method according to the invention.

The method may further comprise the step

- during said control under operator supervision, of adapting the generation of malfunction codes to said control. This may entail certain malfunction codes which may normally be presented during operation of said start/stop functionality being inactivated and hence not being registered and/or displayed. In one version, all or some of the malfunction codes normally relating to start/stop functionality may be generated and presented routinely during the method according to the invention, i.e. when control of said functionality is exercised by the operator,

With advantage, the method according to the invention is applicable on vehicles which are equipped with a combustion engine and a hybrid system, e.g. a parallel hybrid system. Said hybrid systems may for example comprise suitable means for energy storage, e.g. a flywheel, pneumatic accumulator or capacitor. In one example said hybrid system may be provided with an energy store in the form of a battery. The method is therefore versatile.

The method may be implemented in existing motor vehicles. In one aspect of the invention, software for conducting the method according to the invention may be installed in a control unit of the vehicle during the manufacture of the vehicle. A purchaser of the vehicle may thus have the possibility of selecting the function of the method as an option. Alternatively, software comprising programme code for conducting the innovative method for control of operation of a combustion engine of a vehicle may be installed in a control unit of the vehicle on the occasion of upgrading at a service station, in which case said software may be loaded into a memory in the control unit.

Software which comprises programme code for control of operation of a combustion engine of a vehicle will be easy to update or replace. Moreover, different parts of the software which comprises programme code for control of operation of a combustion engine of a vehicle may be replaced independently of one another. This modular configuration is advantageous from a maintenance perspective.

One aspect of the invention is a proposed device for control of operation of a combustion engine of a vehicle, which vehicle has functions of starting and switching off said engine, comprising a start and stop arrangement suited to temporarily switching said engine off with a view to saving fuel during routine driving. The device comprises means suited to controlling at least said start and stop arrangement under operator supervision during functional testing of the vehicle.

One aspect of the invention is a proposed device for control of operation of a combustion engine of a vehicle, which vehicle has functions suited to starting and switching off said engine both via ignition switch and via a start and stop arrangement for temporarily switching said engine off with a view to saving fuel during routine driving. The device comprises means suited to controlling at least said start and stop arrangement under operator supervision during functional testing of the vehicle. The device may comprise

- means suited to controlling both said start and stop arrangement and the function of starting and switching off said engine via an ignition switch under operator supervision. The device may comprise

- means suited, during said control under operator supervision, to overriding at least certain existing predetermined conditions for allowing starting and/or switching off of said engine. The device may comprise

- means suited, during said control under operator supervision, to adding further predetermined conditions to existing predetermined conditions for allowing starting and/or switching off of said engine. The device may comprise - means suited to controlling said start and stop arrangement for temporary switching off both in the form of discrete starts and stops and in the form of starts and stops according to a predetermined sequence. The device may comprise

- means suited to controliing said functions by means of an external operator device.

The device may comprise

- means suited to controlling said functions by means of operator devices which are internal to the vehicle.

The device may comprise

- means suited, during said control under operator supervision, to adapting functions relating to starting and/or switching off said engine to said control.

In one version any malfunction codes relating to start/stop functionality are generated routinely but an operator of the vehicle may opt to disregard them when applying the method according to the invention. The device may comprise

- means suited, during said control under operator supervision, to adapting the generation of malfunction codes to said control.

Various means proposed for performing a certain function are herein described. It should be noted that said means are adapted or provided to perform said functions.

One aspect of the invention is a proposed motor vehicle provided with a device according to any one of claims 10-18. Said vehicle may be any from among truck, bus or car. it may be a hybrid vehicle. It may alternatively be a lift truck, dumper, bucket excavator, crane, forestry machine, mining machine, utility vehicle or some other suitable platform. One aspect of the invention is a proposed computer programme for control of operation of a combustion engine of a vehicle, which programme comprises programme code stored on a computer-readable medium for causing an electronic control unit or another computer connected to the electronic control unit to perform steps according to any one of claims 1-9.

One aspect of the invention is a proposed computer programme for control of operation of a combustion engine of a vehicle, which programme comprises programme code for causing an electronic control unit or another computer connected to the electronic control unit to perform steps according to any one of claims 1 -9.

One aspect of the invention is a proposed computer programme product which comprises a programme code stored on a computer-readable medium for performing method steps according to any one of claims 1-9 when said programme code is run on an electronic control unit or another computer connected to the electronic control unit. Further objects, advantages and novel features of the present invention will become apparent to one skilled in the art from the following details, and also by putting the invention into practice. Whereas the invention is described below, it should be noted that it is not confined to the specific details described. One skilled in the art having access to the teachings herein will recognise further applications, modifications and incorporations in other fields, which are within the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS For fuller understanding of the present invention and its further objects and advantages, the detailed description set out below should be read in conjunction with the accompanying drawings, in which the same reference notations denote similar items in the various diagrams, and

Figure 1 schematically illustrates a vehicle according to an embodiment of the invention;

Figure 2 schematically illustrates a subsystem of the vehicle depicted in Figure 1 , according to an embodiment of the invention;

Figure 3 schematically illustrates a subsystem of the vehicle depicted in Figure 1 , according to an embodiment of the invention;

Figure 4a is a schematic flowchart illustrating a method according to an embodiment of the invention;

Figure 4b is a more detailed schematic flowchart illustrating a method according to an embodiment of the invention; and

Figure 5 schematically illustrates a computer according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

Figure 1 depicts a side view of a vehicle 100. The vehicle exemplified comprises a tractor unit 1 10 and a semitrailer 112. The vehicle may be a heavy vehicle, e.g. a truck or a bus. it may alternatively be a car. The vehicle comprises in one aspect of the invention a control unit with so-called start/stop functionality. It may be a hybrid vehicle provided with a combustion engine and an electric drive system. It may be a hybrid vehicle provided with a combustion engine and a regenerative brake system. It may be a vehicle which only has for its propulsion a combustion engine, which may be an Otto engine or a diesel engine.

The term "link" refers herein to a communication link which may be a physical connection such as an opto-electronic communication line, or a non-physical connection such as a wireless connection, e.g. a radio link or microwave link. The term "regenerative brake system" refers herein to a suitable regenerative brake system arranged to be able to store energy imparted and thereafter use said stored energy in suitable ways. A parallel hybrid system comprising an energy store and an electrical machine is herein described but is merely one example of a regenerative brake system.

The term "routine driving" of the vehicle 100 refers herein to its ordinary, normal or usual driving. It covers various kinds of driving of the vehicle which may occur in its day-to-day use. In one example such use comprises day-to- day driving in urban environments in which the vehicle has at times to come to a complete halt at a traffic signal or a road sign or during queuing or traffic hold-ups. In another example such use comprises day-to-day driving in urban environments where the vehicle has at times to start from stationary, e.g. after coming to a halt at a traffic signal or a road sign. Said start and stop arrangement is herein described as intended for temporary switching off of said engine with a view to saving fuel during routine driving. This is to be interpreted as described above.

The method according to the invention and the device according to the invention are well suited in one aspect of the invention to other platforms than motor vehicles, e.g. watercraft. The watercraft might be of any suitable kind, e.g. motorboats, steamers, ferries, submarines, hovercraft or ships.

The method according to the invention and the device according to the invention are also well suited in one aspect of the invention to, for example, a rock crusher or the like.

The method according to the invention and the device according to the invention are also well suited in one aspect of the invention to systems which for example comprise industrial engines and/or engine-powered industrial robots. The method according to the invention and the device according to the invention are also well suited in one aspect of the invention to various kinds of power plants, e.g. an electrical power plant which comprises a diesel generator.

The method according to the invention and the device according to the invention are well suited to any suitable propulsion system which comprises a prime mover and start/stop functionality, e.g. on a locomotive or some other platform.

Figure 2 depicts a parallel hybrid system 299 of the vehicle 100. The parallel hybrid system is situated in the tractor unit 110.

The parallel hybrid system 299 comprises a combustion engine 230 which has an output shaft 235 connected to a clutch 240 which may be any suitable clutch. It might be a sliding clutch with pressure plate and disc. In one alternative the clutch might be implemented as a so-called lock-up function in a torque converter in cases where the vehicle's transmission has an automatic gearbox. The clutch is connected to an input shaft 245 of a gearbox 260. The gearbox has an output shaft 265 connected to a torque distributor 270 for transfer of power to a number of tractive wheels 280 via respective driveshafts 275.

The parallel hybrid system 299 further comprises an electrical machine configuration comprising an electrical machine 250 situated on the input shaft 245 of the gearbox 280. The electrical machine is connected electrically to an energy store 255. The electrical machine may in one example be arranged for an operating power output of 60-120 kW. The energy store may be of any suitable kind. It may in one example be a battery of any suitable kind, e.g. a lithium ion battery. It may alternatively be for example an NiMH battery. It may in another example be an electrochemical energy store, e.g. an electrochemical capacitor, a so-called SuperCap. Said energy store is herein exemplified by a battery of a conventional kind for parallel hybrid systems.

The electrical machine 250 is arranged in one version to be energised by said energy store 255 and thereby serve as a prime mover for the vehicle's power train in order to impart propulsive torque to the gearbox input shaft 245. The electrical machine is suited in one version to serving as a generator for the electrical machine configuration and thus charge the energy store 255 during braking of the vehicle. Said electrical machine may typically serve alternately as motor and generator. During regenerative braking of the vehicle, braking torque is applied to the input shaft 245, thereby charging the energy store 255.

In this embodiment example the battery 255 is connected electrically to an electrical rectifier 253 by a cable L255. The rectifier is suited to converting a DC voltage drawn from the battery via the cable L255 to a desired suitable three-phase voltage. The rectifier is suited to supplying this three-phase voltage to the electrical machine 250 via a cable L253 to energise and operate the electrical machine. Said DC voltage may be up to several hundred volts, e.g. 300 or 700 volts.

Said electrical machine configuration comprises said electrical machine 250, rectifier 253, battery 255 and necessary connections between them. The rectifier is appropriately arranged to respond to regenerative braking of the vehicle by converting to a DC voltage a three-phase voltage generated from the electrical machine 250 and supplied to the rectifier. The rectifier is arranged to supply said DC voltage to the battery 255 via the cable L255 in order to charge the battery.

The electrical machine configuration herein referred to takes the form of a component configuration comprising the electrical machine 250, the cable L253, the rectifier 253, the cable L255 and the energy store 255, but It should be noted that different versions of said electrical machine configuration are feasible. In one version the energy store and the rectifier may be manufactured as an integral unit connected electrically to the electrical machine. In another version the rectifier and the electrical machine may be manufactured as an integral unit connected electrically to the energy store. In a third version the energy store, the rectifier and the electrical machine may be manufactured as an integral unit. In one version at least one consumer unit 290 is connected electrically to an output side of the battery 255 and might for example be an AC (air conditioning) ancillary unit or cab fan. The battery 255 is suited to supplying said at least one consumer unit 290. In another version said parallel hybrid system has no such consumer unit. Alternatively said consumer unit may be arranged to be supplied directly by some other power source than said battery 255, e.g. the electrical machine 250.

A first control unit 210 is arranged for communication with the engine 230 via a link L230. The first control unit is adapted to controlling the operation of the engine according to stored operating routines. It is for example adapted to guiding a prevailing speed of the engine (or torque of the output shaft) towards a required speed (or required torque of the output shaft). The first control unit is provided with start/stop functionality. It is thus adapted to switching the engine off when this is appropriate during routine operation of the vehicle, e.g. when it is stationary at a traffic signal, e.g. a red light, or is loading or unloading freight. In this context the first control unit is adapted to starting the engine when this is appropriate during routine operation of the vehicle, e.g. when traffic signals turn green or the loading or unloading of freight has been completed.

The first control unit 210 is arranged for communication with a communication terminal 205 internal to the vehicle via a link L205. Said terminal 205 may be situated in a cab of the vehicle, e.g. as part of an instrument pane!. Said terminal may comprise a viewing screen, e.g. a touchscreen, and may comprise a set of push-buttons or other suitable means for conducting the innovative method, e.g. for starting and switching off said engine 230 via said start/stop functionality of the first control unit. An operator of the vehicle, e.g. a driver, workshop technician or service technician, may use said communication terminal 205 to control the operation of the engine via said start/stop functionality which is stored in the first control unit. An operator of the vehicle may thus use said terminal 205 to switch said engine off manually via said start/stop functionality. An operator may likewise use said terminal 205 to start said engine manually via said start/stop functionality.

The first control unit 210 is arranged for communication with a communication terminal 207 external to the vehicle via a link L207. Said link L207 may be a physical connection arranged detachably for communication with the first control unit, e.g. via a communication network internal to the vehicle. Said network may comprise a CAN bus. In one alternative said terminal 207 is arranged for wireless communication with the first control unit. It may be a handheld electronic device. It may comprise a viewing screen, e.g. a touchscreen and may comprise a set of push-buttons or other suitable means for conducting the innovative method, e.g. for starting and switching off said engine 230 via said start/stop functionality of the first control unit. Said operator of the vehicle may use said terminal 207 to control the operation of the engine via said start/stop functionality which is stored in the first control unit. An operator or the vehicle may thus use said terminal 207 to switch said engine off manually via said start/stop functionality. An operator may likewise use said terminal 207 to start said engine manually via said start/stop functionality.

Said start/stop functionality may take the form of a start and stop arrangement which may be incorporated in the first control unit 210 and/or the second control unit 220. In such cases said start/stop functionality will be implemented in the form of software code run by the first control unit 210 and/or the second control unit 220. A number of conditions relating to said start/stop functionality may be predetermined and be also stored in a memory of the first control unit 210.

There may in one example be a set of conditions relating to starting said engine 230 by means of said start/stop functionality. Said predetermined set of conditions may be applied when starting said engine via said start/stop functionality during routine operation. In one aspect of the method according to the invention said predetermined set of conditions may be adapted, in which case one or more of said conditions may be inactivated when said start/stop functionality is managed under operator control according to the invention. Further conditions may also be added to said predetermined set of conditions when said start/stop functionality is managed under operator control according to the invention.

One example of said conditions for starting the vehicle 100 by means of said start/stop functionality might be that a prevailing temperature of a certain component or device of the vehicle be above or below a predetermined threshold value. One example of a condition for starting the vehicle by means of said start/stop functionality which might be added to said set of conditions is that a handbrake of the vehicle be activated.

There may in one example be a set of conditions relating to switching said engine 230 off by means of said start/stop functionality. Said predetermined set of conditions may be applied when starting said engine via said start/stop functionality during routine operation. In one aspect of the method according to the invention said predetermined set of conditions may be adapted. Thus one or more of them may be inactivated when said start/stop functionality is managed under operator control according to the invention. Further conditions may also be added to said predetermined set of conditions when said start/stop functionality is managed under operator control according to the invention. One example of said conditions for switching the vehicle 100 off by means of said start/stop functionality might be that a prevailing temperature of a certain component or device of the vehicle be above or below a predetermined threshold value. One example of a condition for starting the vehicle by means of said start/stop functionality which might be added to said set of conditions is that a handbrake of the vehicle be activated.

Certain of said conditions for switching off or starting said engine 230 by means of said start/stop functionality, during routine operation or according to the method of the invention, may be so-called critical conditions. If a critical condition is not fulfilled, said desired starting or switching off of said engine by means of said start/stop functionality cannot take place. Any starting or switching off of said engine when a critical condition is not fulfilled might cause damage to systems of the vehicle or to objects or individuals in its surroundings.

In one embodiment of the present invention certain of said conditions relating to starting or switching off by means of said start/stop functionality may, where appropriate, be overridden by the first control unit 210, provided that they are not so-called critical conditions.

The first control unit is arranged, for cases where at least one critical condition is not fulfilled, not to allow starting or switching off of said engine by means of said start/stop functionality. In one embodiment example an operator may use said communication terminal internal or external to the vehicle to input a predetermined sequence list which specifies desired start and switch-off times for said engine. In this case the first control unit is adapted to controlling the starting and switching off of said engine according to said list.

There may in one example be a set of control actions related to starting said engine by means of said start/stop functionality. Said predetermined set of control actions may be applied when starting said engine via said start/stop functionality during routine operation. In one aspect of the method according to the invention said predetermined set of control actions may be adapted. Thus one or more of them may be inactivated when said start/stop functionality function is managed under operator control according to the invention. Further control actions may also be added to said predetermined set of control actions when said start/stop functionality function is managed under operator control according to the invention. Possible examples of such control actions relating to starting the vehicle by means of said start/stop functionality might be that a certain damper or ancillary of the vehicle be operated or controlled in a certain way, or that an adaptation process be conducted or not, or that cooling of a component be required or not.

There may in one example be a set of control actions related to switching said engine off by means of said start/stop functionality. Said predetermined set of control actions may be applied when switching off said engine via said start/stop functionality during routine operation. In one aspect of the method according to the invention said predetermined set of control actions may be adapted. Thus one or more of them may be inactivated when said start/stop functionality function is managed under operator control according to the invention. Further control actions may also be added to said predetermined set of control actions when said start/stop functionality function is managed under operator control according to the invention. Possible examples of such control actions relating to switching the vehicle 100 off by means of said start/stop functionality might be that a certain damper or ancillary of the vehicle be operated or controlled in a certain way, or that an adaptation process be conducted or not, or that warming of a component be required or not. An example of a control action which is related to switching the vehicle off by means of said start/stop functionality and which may be added to said set of control actions is adjusting a differential pressure sensor of the vehicle at or immediately after the time when the engine is switched off.

The first control unit 210 is arranged for communication with the clutch 240 via a link L240 and is adapted to controlling the operation of the clutch according to stored operating routines. It is for example adapted to opening the clutch, sliding it together and closing it according to said stored operating routines.

The first control unit 210 is arranged for communication with the electrical machine 250 via a link L250 and is adapted to controlling the operation of the electrical machine according to stored operating routines. Although in Figure 2 the link L250 is connected to the electrical machine 250 it is in practice connected to the electrical rectifier 253. In practice the first control unit is adapted to controlling the electrical machine by means of the rectifier. For example the first control unit is adapted to choosing the electrical machine's direction according to said stored operating routines. This means that the first control unit is adapted to using the rectifier to cause the electrical machine to serve as a motor and thereby impart propulsive torque to the input shaft 245 of the gearbox 280. It also means that the first control unit is adapted, where appropriate, to causing the electrical machine to serve as a generator in order to charge the battery 255, e.g. during regenerative braking according to the invention. The first: control unit 210 is arranged for communication with the gearbox 260 via a link L280 and is adapted to controlling the operation of the gearbox according to stored operating routines. It is for example adapted to effecting various gearsteps in the gearbox, including neutral position, according to said stored operating routines. The gearbox may be a so-called manual gearbox, e.g. a robotised/automated manual gearbox, or an automatic gearbox.

A second control unit 220 is arranged for communication with the first control unit 210 via a link L220. This second control unit may be detachably connected to the first control unit 210. It may be a control unit external to the vehicle 100. It may be adapted to performing the innovative method steps according to the invention. It may be used to cross-load software to the first control unit 210, particularly software for applying the innovative method. It may alternatively be arranged for communication with the first control unit via an internal network of the vehicle. It may be adapted to performing substantially similar functions to those of the first control unit, e.g. controlling the operation of the engine 230, the clutch 240, the electrical machine configuration comprising the electrical machine 250, the rectifier 253 and the battery 255, and the gearbox 280. The second control unit 220 may be adapted to performing substantially similar functions to those of the first control unit 210, e.g. controlling at least said start and stop arrangement under operator supervision during functional testing of the vehicle.

It should be noted that certain of the aforesaid functions may be performed by the first control unit 210 and certain of them by the second control unit

The first control unit 210 is adapted to controlling under operator supervision the switching off of said engine 230.

It is likewise adapted to controlling under operator supervision the starting of said engine. The first control unit 210 is adapted to effecting under operator supervision the switching off of said engine 230 by means of a virtual switch-off command. It is likewise adapted to effecting under operator supervision the starting of said engine by means of a virtual start command. Said start command and switch-off command may be executed by said operator by means of said communication terminal 205 internal to the vehicle or said communication terminal 207 external to the vehicle. Said operator may thus achieve starting and switching off of said engine without having to use a conventional starting key or start/switch -off button of the vehicle.

The first control unit 210 comprises functions of starting and switching off said engine both via an ignition switch and via a start and stop arrangement for temporarily switching said engine off with a view to saving fuel during routine driving. It is adapted to controlling said start and stop arrangement under operator supervision during functional testing of the vehicle. In one embodiment example it is adapted to controlling both said start and stop arrangement and the function of starting and switching off said engine via ignition switch under operator supervision, in one embodiment example it is adapted, during said control under operator supervision, to overriding at least certain existing predetermined conditions for allowing starting and/or switching off of said engine. In one embodiment example it is adapted, during said control under operator supervision, to adding further predetermined conditions to existing predetermined conditions for allowing starting and/or switching off of said engine, in one embodiment example it is adapted to controlling said start and stop arrangement for temporary switching off both in the form of discrete starts and stops and in the form of starts and stops according to a predetermined sequence. In one embodiment example the first control unit is adapted to controlling said start/stop function by means of an external operator device, also called communication terminal 207 external to the vehicle. In one embodiment example it is adapted to controlling said start/stop function by means of operator devices internal to the vehicle, e.g. said internal communication terminal 205. In one embodiment example it is adapted, during said control under operator supervision, to adapting functions relating to starting and/or switching off said engine to said control (addition of functions which do not normally relate to start/stop). In one embodiment example it is adapted, during said control under operator supervision, to adapting conditions and/or control actions which relate to starting and/or switching off said engine to said control. In one embodiment example it is adapted, during said control under operator supervision, to adapting functions relating to starting and/or switching off said engine to said control. In one embodiment example it is adapted, during said control under operator supervision, to adapting the generation of malfunction codes to said control.

When said engine 230 is switched off under operator supervision via said start/stop functionality, the vehicle may still be running by said hybrid system and/or other systems on board possibly being energised, activated and/or in operation.

When the engine is switched off according to the method of the invention, it will therefore be completely shut down, i.e. it will not even run at an idling speed.

Figure 3 illustrates schematically a subsystem 399 of the vehicle 100. This subsystem is situated in the tractor unit 110. The subsystem 399 comprises a combustion engine 230 with an output shaft 235 connected to a clutch 240. The clutch may be any suitable clutch. It might be a sliding clutch with pressure plate and disc. It might in one alternative be implemented as a so-called lock-up function in a torque converter in cases where the vehicle's transmission has an automatic gearbox. The clutch is connected to an input shaft 245 of a gearbox 260. The gearbox has an output shaft 265 connected to a torque distributor 270 for transfer of power to a number of tractive wheels 280 via respective c!riveshafts 275.

The subsystem 399 comprises the previously described first control unit 210 and second control unit 220, which are provided with said start/stop functionality and are thus adapted to controlling the switching off and starting of said engine according to the method of the invention.

Said subsystem 399 further comprises said communication terminal 205 internal to the vehicle and said communication terminal 207 external to the vehicle.

An operator may thus control at least said start and stop arrangement manually (under operator supervision) during functional testing of the vehicle, in a similar way to that described with reference to Figure 2 above except that in this case the vehicle is not a hybrid vehicle. Said start/stop functionality may therefore be installed in the first control unit 210 and/or the second control unit 220 of a vehicle which is only powered by a combustion engine.

When said engine is switched off under operator supervision via said start/stop functionality, the vehicle may still be running by other systems on board possibly being energised, activated and/or in operation. When the engine is switched off according to the method of the invention, it will therefore be completely shut down, i.e. it will not even run at an idling speed.

Figure 4a is a schematic flowchart illustrating a method for control of operation of a combustion engine of a vehicle, which vehicle has functions of starting and switching off said engine both via ignition switch and via a start and stop arrangement for temporarily switching said engine off with a view to saving fuel during routine driving, according to an embodiment of the invention. The method comprises a first step s401 comprising the step of - controlling at least said start and stop arrangement under operator supervision during functional testing of the vehicle. The method ends after step s401. Figure 4b is a schematic flowchart illustrating a method for control of operation of a combustion engine of a vehicle, which vehicle has functions of starting and switching off said engine both via ignition switch and via a start and stop arrangement for temporarily switching said engine off with a view to saving fuel during routine driving, according to an embodiment of the invention.

The method comprises a first step s410 comprising the step of initiating starting of said engine 230 via said start/stop functionality. This is effected by an operator of the vehicle, e.g. by means of said communication terminal 205 internal to the vehicle or said communication terminal 207 external to the vehicle. Said operator may thus send to the first control unit 210 via the link L205 or L207 a demand to start said engine. Step s410 is followed by a step s420. Method step s420 comprises the step of evaluating said set of predetermined conditions relating to said starting of the engine 230 via said start/stop functionality of the first control unit 210. This may entail certain predetermined conditions being inactivated. Further conditions may be added to said set of conditions. Where appropriate, at least one predetermined or added condition may be overridden. It is also possible to establish whether relevant conditions among said set of conditions are fulfilled or not and whether at least one critical condition is not fulfilled.

If all of the appropriate conditions relating to starting the engine are fulfilled, starting may be allowed and initiated. In this context certain predetermined conditions for starting may be overridden and thereby inactivated, in which case a step s430 follows. If all of the critical conditions relating to starting the engine are fulfilled, starting may be allowed and initiated, in which case a step s430 follows, if not all of the conditions, including critical conditions, are fulfilled, the method ends. At method step s420 the control actions relating to starting by means of said start/stop functionality which are to take place are also determined. This may entail certain predetermined control actions being activated or inactivated. Further control actions may be added to a predetermined set of control actions which relate to said starting of the engine. Where appropriate, at least one predetermined or added condition may be activated or inactivated.

Method step s430 comprises the step of starting the engine 230 under operator control by means of said start/stop functionality. The appropriate control actions established at step s420 may take place simultaneously or in series. Step s430 is followed by a step s440.

The method step s440 comprising the step of initiating switching off of said engine 230 via said start/stop functionality is effected by an operator of the vehicle, e.g. by means of said communication terminal 205 internal to the vehicle or said communication terminal 207 external to the vehicle. Said operator may thus send to the first control unit 210 via the link L205 or L207 a demand to switch said engine off. Step s440 is followed by a step s450.

Method step s450 comprises the step of evaluating said set of predetermined conditions relating to said switching off of the engine via said start/stop functionality of the first control unit 210. This may entail certain predetermined conditions being inactivated. Further conditions may be added to said set of conditions. Where appropriate, at least one predetermined or added condition may be overridden. It is also possible to establish whether relevant conditions among said set of conditions are fulfilled or not and whether at least one critical condition is not fulfilled. If all of the appropriate conditions relating to switching the engine off are fulfilled, switching off may be allowed and initiated. In this context certain predetermined conditions for switching off may be overridden and thereby inactivated, in which case a step s460 follows. If all of the critical conditions relating to switching the engine off are fulfilled, switching off may be allowed and initiated, in which case a step s460 follows. If not all of the conditions, including critical conditions, are fulfilled, the method ends.

At step s450 the control actions relating to switching off by means of said start/stop functionality which are to take place are also determined. This may entail certain predetermined contro! actions being activated or inactivated. Further control actions may be added to a predetermined set of control actions which relate to said switching off of the engine. Where appropriate, at least one predetermined or added condition may be activated or inactivated.

Method step s450 is followed by step s480.

Method step s480 comprises the step of switching the engine 230 off under operator control by means of said start/stop functionality. The appropriate control actions established at step s450 may take place simultaneously or in series.

The method ends after step s460.

In an alternative version, steps s440, s450 and s480 may take place before steps s410, s420 and s430. In this case, switching the engine off via said start/stop functionality is thus initiated first, followed by starting of said engine via said start/stop functionality being initiated.

Figure 5 is a diagram of one version of a device 500. The control units 210 and 220 described with reference to Figure 2 may in one version comprise the device 500 which itself comprises a non-volatile memory 520, a data processing unit 510 and a read/write memory 550, The non-vo!atile memory 520 has a first memory element 530 in which a computer programme, e.g. an operating system, is stored for controlling the operation of the device 500. The device 500 further comprises a bus controller, a serial communication port, I/O means, an AID converter, a time and date input and transfer unit, an event counter and an interruption controller (not depicted). The non-volatile memory 520 has also a second memory element 540. A proposed computer programme P comprises routines for controlling the operation of a combustion engine of a vehicle, which vehicle has functions of starting and switching off said engine both via ignition switch and via a start and stop arrangement for temporarily switching said engine off with a view to saving fuel during routine driving.

The computer programme P may comprise routines for controlling both said start and stop arrangement and the function of starting and switching off said engine via ignition switch under operator supervision. It may comprise routines, during said control under operator supervision, for overriding at least certain existing predetermined conditions for allowing starting and/or switching off of said engine. It may comprise routines, during said control under operator supervision, for adding further predetermined conditions to existing predetermined conditions for allowing starting and/or switching off of said engine. It may comprise routines for controlling said start and stop arrangement for temporary switching off both in the form of discrete starts and stops and in the form of starts and stops according to a predetermined sequence. It may comprise routines for controlling functions by means of an external operator device. It may comprise routines for controlling said functions by means of operator devices interna! to the vehicle. It may comprise routines, during said control under operator supervision, for adapting functions relating to starting and/or switching off said engine to said control. It may comprise routines, during said control under operator supervision, for adapting the generation of malfunction codes to said control.

The computer programme P may be stored in an executable form or in compressed form in a memory 560 and/or in a read/write memory 550.

Where the data processing unit 510 is described as performing a certain function, it means that the data processing unit conducts a certain part of the programme stored in the memory 560 or a certain part of the programme stored in the read/write memory 550.

The data processing device 510 can communicate with a data port 599 via a data bus 515. The non-voiatiie memory 520 is intended for communication with the data processing unit 510 via a data bus 512. The separate memory 560 is intended to communicate with the data processing unit via a data bus 51 1 . The read/write memory 550 is adapted to communicating with the data processing unit via a data bus 514. The data port 599 may have for example the links L205, L207, L220, L230, L240, L250 and L260 connected to it (see Figure 2 and figure 3).

When data are received on the data port 599, they are stored temporarily in the second memory element 540. When input data received have been temporarily stored, the data processing unit 510 will be prepared to conduct code execution as described above. In one version, signals received on the data port 599 contain information about an operator demanding that the engine be started, according to one aspect of the present invention. In one version they contain information about an operator demanding that the engine be switched off, according to one aspect of the present invention. In one version they contain information about starts and stops of said

combustion engine 230 according to a desired or predetermined sequence. The signals received on the data port 599 may be used by the device 500 to control at least said start and stop arrangement under operator supervision during functional testing of the vehicle. Parts of the methods herein described may be conducted by the device 500 by means of the data processing unit 510 which runs the programme stored in the memory 560 or the read/write memory 550. When the device 500 runs the programme, methods herein described are executed. The foregoing description of the preferred embodiments of the present invention is provided for illustrative and descriptive purposes. It is not intended to be exhaustive, nor to restrict the invention to the variants described. Many modifications and variations will obviously suggest themselves to one skilled in the art. The embodiments have been chosen and described in order best to explain the principles of the invention and their practical applications and thus make it possible for one skilled in the art to understand the invention for different embodiments and with the various modifications appropriate to the intended use.