PURPOSE: To automatically correct the time disorder of trouble record read data by providing a reader with a clock function and constituting a system which sets the time of this clock to the correct time (absolute time).

CONSTITUTION: This reader reads the trouble record from a trouble recorder incorporating the clock function, and a clock function 3B is provided on the side of a reader 3A and the time of this reader is set to the correct time; and when there is a difference between the time of this clock function 3B and that of a clock function 2C of a trouble recorder 1, both times are compared with each other to calculate the disorder and the time of trouble occurrence is outputted after being corrected at the time of outputting trouble record data. That is, the true time of trouble occurrence is automatically calculated and the data output time is automatically corrected. Thus, the reliability of trouble records and data is very high.