PURPOSE: To provide a control device for vehicle in which the disconnection of an earthing conductor can be precisely identified from the disconnection of a signal line or a normal state.

CONSTITUTION: The signal lines of an oil temperature sensor 16, a water temperature sensor 15 and an engine rotating speed sensor 19 are connected to input circuits 21A, 21B, 22A, respectively, by commonly using an earth terminal 20A. A microcomputer 27 detects the detection signal of the oil temperature sensor 16 and intermittently repeats to identify whether it is within a predetermined failure detecting range or not. When the frequency of judgment of the failure detecting range reaches a prescribed limit value, an engine 11 and an automatic transmission 12 are made to execute a fail-safe control. Since the earth terminal 20A is commonly used, the number of connector pins or the number of wirings is reduced, and no special circuit for detecting the disconnection of an earthing conductor is needed.