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XB67 - Check ACP VREF/ACP SIG RTN For Intermittent Open



- Key "OFF".

- A/C "OFF".

- Disconnect A/C Pressure (ACP) sensor. Inspect for damaged or pushed out pins, corrosion, loose wires, etc. Service as necessary.

- Key "ON".

- Connect test lamp between ACP VREF and ACP SIG RTN circuits at the ACP sensor vehicle harness connector (if test lamp will not light sufficiently, use Digital Volt/Ohm Meter (DVOM) to monitors volts).

- Observe test lamp/DVOM for an indication of a fault while performing the following (the test lamp will go out, or the DVOM voltage will drop, indicating an open circuit):

- Shake, wiggle, bend the ACP VREF and ACP SIG RTN circuits between the ACP sensor vehicle harness connector and the Variable Control Relay Module (VCRM).

- Lightly tap the VCRM (to simulate road shock).

- Key "OFF".

- Is a fault indicated?

Yes -- Isolate fault and service as necessary. Reconnect all components. Start engine, A/C "ON". wait 20 seconds. Key "OFF". Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)

No -- Go to XB68. XB68 - Check ACP Signal: Intermittent Short to Ground or Power