Refrigerant Pressure Sensor / Switch: Testing and Inspection
A/C Pressure Switch Circuit Troubleshooting1. Disconnect the A/C pressure switch 2P connector.
2. Turn the ignition switch ON (II).
3. Measure the voltage between the No 2 terminal of the A/C presure switch 2P connector and body ground.
Is there battery voltage?
YES - Go to step 4.
NO - Go to step 10.
4. Turn the ignition switch OFF.
5. Check for continuity between the No. 1 and No. 2 terminals of the A/C pressure switch.
Is there continuity?
YES - Go to step 6.
NO - Go to step 11.
6. Reconnect the A/C pressure switch 2P connector.
7. Disconnect the heater control panel 30P connector.
8. Turn the ignition switch ON (II).
9. Measure the voltage between the No. 23 terminal of the heater control panel 30P connector and body ground.
Is there battery voltage?
YES - Check for loose wires or poor connections at the heater control panel 30P connector and at the A/C pressure switch 2P connector. If the connections are good, substitute a known-good heater control panel, and recheck. If the symptom/indication goes away, replace the original heater control panel.
NO - Repair open in the wire between the heater control panel and the A/C pressure switch.
10. Using a backprobe set, measure the voltage between the No. 27 terminal of PCM connector A (32P) and body ground with the PCM connectors connected.
Is there battery voltage?
YES - Check for loose wires or poor connections at the PCM connector A (32P). If the connections are good, substitute a known-good PCM, and recheck. If the symptom/indication goes away, replace the original PCM.
NO - Repair open in the wire between the PCM and the A/C pressure switch.
11. Check for proper A/C system pressure.
Is the pressure within specifications?
YES - Replace the A/C pressure switch.
NO - Repair the A/C pressure problem.