XB151 - Check Power to Pump and FP Circuits

- Start engine.

CAUTION: While performing this test, do not touch any moving/hot engine parts.

- Disconnect High Speed Fuel Pump (HFP) relay (located in power distribution box).

- Connect a test lamp between the power-to-pump circuit at the HFP relay vehicle harness connector and chassis ground.

- Observe test lamp for an indication of a fault while performing the following: (The lamp will go out if an open or Fuel Pump (FP) circuit short to power is detected. Also listen for engine stall/stumble or the fuel pump turning off. A fuel pressure gauge could also be installed and monitored.)

- For Diagnostic Trouble Codes (DTC) 524/543: shake, wiggle, bend the power-to-pump circuit from the Variable Control Relay Module (VCRM) to the Fuel Pump Monitor (FPM) splice and the B(+) circuit to Pins 4 and 5 at the VCRM.

- For DTC 556: shake, wiggle, bend the FP circuit from the VCRM to Powertrain Control Module (PCM).

- Key "OFF".

- Reconnect HFP relay.

- Is fault indicated?

Yes -- Isolate fault and service as necessary. Clear continuous memory. Clearing Diagnostic Trouble Codes

Reconnect all components. Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- If DTC 556 was present: Go to XB152. XB152 - Check FP Circuit For Intermittent Short to Ground

If DTC 556 was not present: Go to XB158. XB158 - Check Left O2S Circuit For Intermittent Short to Power