XB68 - Check ACP Signal: Intermittent Short to Ground or Power
- Key "OFF".
- A/C Pressure (ACP) sensor disconnected.
- Connect test lamp or Digital Volt/Ohm Meter (DVOM) (which ever was used in previous step) between ACP VREF and ACP signal circuit at the ACP sensor vehicle harness connector.
- Key "ON".
- Observe test lamp/DVOM for an indication of a fault while performing the following (the lamp will come on, or DVOM will read 5V, indicating an ACP signal short to ground):
- Shake, wiggle, bend the ACP signal from the ACP sensor vehicle harness connector to the Variable Control Relay Module (VCRM).
- Lightly tap the VCRM (to simulate road shock).
- Reconnect test lamp/DVOM between ACP SIG RTN and ACP signal circuit at the ACP sensor vehicle harness connector.
- Again, observe test lamp/DVOM for an indication of a fault while performing the following (the test lamp will come on, or DVOM voltage will increase, indicating an ACP signal short to power).
- Shake, wiggle, bend the ACP signal from the ACP sensor vehicle harness connector to the 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. A/C "OFF", key "OFF". Rerun quick test. Quick Test Appendix (Detailed Testing Instructions)
No -- Go to XB69. XB69 - Check ACP Signal For Intermittent Operation