Fuel Pump: Testing and Inspection

Diagnostic Chart:

DIAGNOSTIC CHART

CHECK OPERATING SOUND OF FUEL PUMP

Make sure fuel pump operates for two seconds after turning ignition switch ON.

CHECK FUEL PUMP

Fuel Pump Terminals:

Apply 12V power supply to pump connector terminal as shown; check if pump operates.

WARNING:
^ Wipe fuel completely off pump.
^ Keep battery as far away from pump as possible.
^ Turn 12 Volt supply ON and OFF on the battery side.
^ Do not run pump for a long time under no-load condition.

CHECK FUEL PUMP GROUND CIRCUIT

1. Turn ignition OFF.
2. Unplug fuel pump connector.
3. Measure resistance of harness connector between fuel pump and body.

Connector & Terminal Resistance
(R38) 3 - body 10 Ohms maximum

CHECK POWER SUPPLY TO FUEL PUMP

Voltage Test:

1. Turn ignition ON.
2. Measure voltage of power supply circuit between fuel pump connector and body.

Connector & Terminal Voltage
(R38) 1 - body 10 Volts minimum

CHECK HARNESS CONNECTOR BETWEEN FUEL PUMP AND FUEL PUMP RELAY

Harness Test:

1. Turn ignition OFF.
2. Measure resistance of harness connector between fuel pump and fuel pump relay.

Connector & Terminal Resistance
(R38) 1 - (B41) 4 10 Ohms maximum

CHECK FUEL PUMP RELAY

Fuel Pump Relay:

1. Unplug connectors from fuel pump relay and main relay.
2. Remove fuel pump relay and main relay with bracket.
3. Connect battery to fuel pump relay connector terminals No. 1 and No. 3.
4. Measure resistance between connector terminals of pump relay.

Connector & Terminal Resistance
No. 2 - 4 10 Ohms maximum

CHECK HARNESS CONNECTOR BETWEEN ECM AND FUEL PUMP RELAY

Harness Test:

1. Unplug ECM connectors.
2. Measure resistance of harness connector between ECM and fuel pump relay.

Connector & Terminal Resistance
(E29) 8 - (B41) 3 10 Ohms maximum