Diesel Data: Automotive Repair

Fuel Pump Relay: Testing and Inspection

FUEL PUMP RELAY:

1. Unplug electrical connector from Fuel Pump Relay.
2. Using an Ohmmeter, check that there is continuity between terminals +B and FP.

Checking Fuel Pump Relay For Continuity:





3. Check that there is continuity between terminals +B and FPR.
4. Check that there is NO continuity between terminals +B and PR.
5. If not as specified, replace Fuel Pump Relay.
6. Connect battery current across terminals +B and FPR.

Testing Fuel Pump Relay Operation - Current Applied:





7. Check that there is NO continuity between terminals +B and FP.
8. Check that there is continuity between terminals +B and PR.
9. If not as specified, replace Fuel Pump Relay.
10. Reconnect connector to Fuel Pump Relay.

FUEL PUMP RESISTOR:

1. Unplug the resistor, located on the rear, RH side of the engine compartment.
2. Using an Ohmmeter, measure the resistance between the terminals.

Measuring Fuel Pump Resistor Resistance:






Resistance: Approx. 0.7 Ohms

3. If resistance is not as specified, replace the Fuel Pump Resistor.
4. Reconnect the resistor electrical plug.