XB155 - Continuous Code 542: Check Ckts For Intermittent Open

Continuous Memory Diagnostic Trouble Code (DTC) 542 indicates that one of the following intermittent conditions has occurred:

- Fuel pump circuit activated when Powertrain Control Module (PCM) expected circuit to be off (ex. fuel pump prime or test procedure).

- Open in the Fuel Pump Monitor (FPM), power-to-pump (FPM splice to fuel pump), fuel pump or fuel pump ground circuit.

- FPM or power-to-pump circuit short to power.

- Variable Control Relay Module (VCRM) output driver or HFP relay contacts stuck closed.

- High Speed Fuel Pump (HFP) circuit short to ground.

- Left Heated Oxygen Sensor (HO2S) signal circuit short to power.

- Engine stall due to excessive load.

- Start engine.

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

- Check for engine stall/stumble while performing the following (if possible listen for fuel pump turning off, or install and monitor a fuel pressure gauge):

- Shake, wiggle, bend the power-to-pump circuit from the fuel pump to FPM splice.

- Lightly tap on the fuel pump, Inertia Fuel Shutoff switch and VCRM (to simulate road shock).

- Key "OFF".

- Is fault indicated?

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

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

No -- Go to XB156. XB156 - Check Fuel Pump Circuits For Shorts or Opens