| 摘要 |
PROBLEM TO BE SOLVED: To prevent a PCV(positive crankcase ventilation) drive circuit driving solenoid valves for a multiple cylinder high pressure pump from being damaged thermally and prevent the whole circuit from getting large scale. SOLUTION: An ECU 8 turns on a first relay drive circuit 10A so as to turn on a first relay 7a and a second relay 7b, and then turns on a first PCV drive circuit 9A at a first valve closing time to energize a first solenoid valve. After completing the energization of the first solenoid valve, the ECU turns on a second PCV drive circuit 9B at a second valve closing time to energize forth solenoid valve. After completing the energization of the forth solenoid valve, it changes over from the first relay drive circuit 10A to a second relay drive circuit 10B so s to turn on a third relay 7c and a forth relay 7c, and then turns on the first PCV drive circuit 9A at a third valve closing time to energize a third solenoid valve. After completing the energization of the third solenoid valve, the ECU turns on the second PCV drive circuit 9B at a forth valve closing time to energize to second solenoid valve. |
