XB44 - Check ACP VREF For Intermittent Short to Ground

- Key "OFF".

- Visually check the A/C Pressure (ACP) VREF circuit from the ACP sensor to the Variable Control Relay Module (VCRM).

- Disconnect the ACP sensor. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

- Disconnect VCRM. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

- Connect test lamp between Pin 6 and Pin 20 of the VCRM vehicle harness connector.

- Observe test lamp for an indication of a fault while performing the following (the lamp will come on when a fault is found, indicating a short to ground):

- Shake, wiggle, bend the ACP VREF circuit from the ACP sensor vehicle harness connector and the VCRM vehicle harness connector.

- Is a fault indicated?

Yes -- Isolate fault and service as necessary. Reconnect all components. Start engine, wait 15 seconds. Key "OFF". Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Unable to isolate fault at this time. Reconnect all components. For further diagnosis using the EEC-IV Monitor Box or Scan Tool, go to Normal Scan Data Values. For further diagnosis of this, or any other symptom, return to Diagnostic Routines. Symptom Related Diagnostic Procedures