Circuit/System Testing

Ignition OFF, the fuel pump should not be operating.
- If the fuel pump operates continuously, test for a short to voltage in supply voltage circuit of the fuel pump. If the circuit/connections test normal, replace the fuel pump relay.
Test the fuel pump fuse. The fuse should not be open.
- If the fuel pump fuse is open, test for a short to ground in the supply voltage circuit of the fuel pump. If the circuit/connections test normal, replace the fuel pump.
Ignition OFF, remove the fuel pump relay from the electrical center.
Ignition ON, test for battery voltage between the B+ voltage circuit of the fuel pump relay and ground.
- If less than B+, repair the B+ voltage circuit of the fuel pump relay for an open/high resistance.
Connect a 15 A fused jumper wire between the B+ circuit of the fuel pump relay and the supply voltage circuit of the fuel pump. The fuel pump should operate.
- If the fuel pump does not operate, test for the following conditions:
  - An open/high resistance in the supply voltage circuit of the fuel pump
  - An open/high resistance in the ground circuit of the fuel pump
- If the above circuit/connections test normal, replace the fuel pump.
If all circuit/connections test normal, test or replace the fuel pump relay.