Fuel Pump Control Circuit

SYSTEM DESCRIPTION
The ECM activates the fuel pump for several seconds after the ignition switch is turned on to improve engine startability. If the ECM receives a 180° signal from the camshaft position sensor, it knows that the engine is rotating, and causes the pump to perform. If the 180° signal is not received when the ignition switch is on, the engine stalls. The ECM stops pump operation and prevents battery discharging, thereby improving safety. The ECM does not directly drive the fuel pump. It controls the ON/OFF fuel pump relay, which in turn controls the fuel pump.




Component Description
A turbine type design fuel pump is used in the fuel tank.




CONSULT-II Reference Value in Data Monitor Mode




ECM Terminals and Reference Value
Specification data are reference values and are measured between each terminal and 48 (ECM ground).

EC-F/PUMP-01:

EC-F/PUMP-01 - Connector Views:

WIRING DIAGRAM

M6,E75 Connector Views:

M1,M2,M3,M4,M5,B1,E71,E72,E73 Connector Views:

Step 1:

Step 2:

Step 3:

Step 4:

Step 5:

Step 6:

Step 7:

Step 8:

Step 9:

Step 10:

Step 11:

Step 12:

Step 13:

Step 14:

Step 15:

DIAGNOSTIC PROCEDURE

Component Inspection







FUEL PUMP RELAY-1 AND -2
Check continuity between terminals 3 and 5.
If NG, replace relay.





FUEL PUMP
1. Disconnect fuel pump harness connector.
2. Check resistance between terminals 1 and 2.

Resistance: 0.2 - 5.0 Ohms [at 25 °C (77 °F)]

If NG, replace fuel pump.