CONTROL DEVICE FOR FUEL INJECTION SYSTEM

A control device is included in a fuel injection system. The fuel injection system includes a low pressure pump, a high pressure pump, an accumulator, a fuel injection valve, a relief valve, and a return pipe. The high pressure pump increases a pressure of a fuel discharged from the low pressure pump and discharges high pressure fuel. The accumulator stores the high pressure fuel discharged from the high pressure pump. The relief valve is provided in a high pressure portion provided downstream from the high pressure pump and opens when a high pressure abnormality occurs in the high pressure portion. The return pipe returns the high pressure fuel in the high pressure portion to a low pressure portion provided downstream from the low pressure pump by the relief valve opening.