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Fuel Pump Control Circuit

Fuel Pump Control Circuit

DESCRIPTION

The fuel pump circuit consists of the ECM, fuel pump and fuel pump ECU (which operates the fuel pump). Based on the engine output, the ECM determines the fuel pump speed. The speed is then converted to a duty signal and sent to the fuel pump ECU. Based on the signal sent from the ECM, the fuel pump ECU adjusts the fuel pump operation speed between 3 settings.

Wiring Diagram:






Step 1-2:




Step 2(Continued)-4:




Step 5:




Step 6:




Step 7-8:




Step 9-10:




Step 10(Continued)-11:




INSPECTION PROCEDURE

This troubleshooting procedure is based on the premise that the engine is started. If the engine is not started, proceed to the problem symptoms table.