Fuel Pump Control

SYSTEM DESCRIPTION




Fuel pump ON-OFF control
The ECM activates the fuel pump for several seconds after the ignition switch is turned ON to improve engine start-up. If the ECM receives a 1° signal from the crankshaft position sensor (POS), it knows that the engine is rotating, and causes the pump to activate. If the 1° signal is not received when the ignition switch is ON, the engine stalls. The ECM stops pump operation and prevents the battery from 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.







DIAGNOSTIC PROCEDURE

EC-F/PUMP-01:

WIRING DIAGRAM

COMPONENT INSPECTION

Fuel pump relay




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.