34 the determination in step s 36 is made on the assumption that the vehicle has been decelerated with the foot brake thus the counter a 2 is incremented by 1 each time the ecu 1 determines u201c no u201d in step s 36 although the foot brake has been operated consequently the value of the counter a 2 represents how many times the determination that the foot brake switch 2 is fixed regardless of whether it is u201c on u201d fixedness or u201c off u201d fixedness has been made after finishing the fixedness count routine the ecu 1 shifts the procedure to step s 4 in fig2 in step s 4 the ecu 1 determines whether or not the value of the counter a 2 has reached a failure criterion value a 00 3 for example if the determination in step s 4 is u201c yes u201d the ecu 1 makes the final determination that the foot brake switch 2 is fixed failure determination means and the ecu 1 puts on a warning lamp 6 in step s 8 after resetting the counter a 2 in step s 6 the ecu 1 finishes the routine after the processing of step s 8 if the determination in step s 4 is u201c no u201d the ecu 1 advances the procedure to step s 10 and executes a noise incomplete disconnection count routine when the ecu 1 starts the noise incomplete disconnection count routine the ecu 1 shifts the procedure to step s 52 in fig4 where the ecu 1 determines whether or not the driving state of the vehicle is.