| 摘要 |
PROBLEM TO BE SOLVED: To diagnose whether or not a guard function for limiting an energization time to a coil of an injector is normal without causing unnecessary fuel injection.SOLUTION: An ECU 1 comprises: a drive circuit 4 which makes currents individually flow to coils 11a, 12a of a plurality of injectors; current detection means 6 which detects a current flowing to a current passage 64 which is common to the coils 11a, 12a; energization time guard means 7 which forcibly stops energization by the drive circuit 4 to the coils when it is determined that a continuation time at which the current flows to either of the coils 11a, 12a reaches a guard time Tg or longer on the basis of a detection result Vi of the current detection means 6; and diagnosis means 26 which operates at a non-energization time of fuel injection. The diagnosis means 26 makes the drive circuit 4 energize the coils for a short time in which the injectors are not valve-opened, makes the current continuously flow to the current passage 64 by sequentially switching the coils which are energized, and determines whether or not the energization time guard mean 7 normally stops the energization to the coils.SELECTED DRAWING: Figure 1 |
