Pinpoint Test M: The Air Conditioning (A/C) Is Always On - A/C Mode Always Commanded On
NOTE:
Before carrying out the following test, diagnose any HVAC, PCM or IC DTCs.
- M1 CHECK THE AIR CONDITIONING COMPRESSOR CYCLING SWITCH (ACCS) PCM PID WITH THE A/C OFF
- Start the engine.
- Enter the following diagnostic mode on the scan tool: ACCS PCM PID.
- Select PANEL mode on the HVAC module and make sure the A/C button and indicator are OFF.
- Does the ACCS PCM PID read OFF?
- M2 CHECK THE AIR CONDITIONING SWITCH STATUS (AC_SEL_SW) HVAC PID WITH THE A/C OFF
- Enter the following diagnostic mode on the scan tool: AC_SEL_SW HVAC PID.
- Select PANEL mode on the HVAC module and make sure the A/C button and indicator are OFF.
- Does the AC_SEL_SW HVAC PID read not pressed?
- Yes: GO to M4.
- No: GO to M3 .
- M3 CHECK THE HVAC MODULE CONNECTION
- Inspect the module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the HVAC module connectors.
- Clear the DTCs.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes: INSTALL a new HVAC module. REFER to CLIMATE CONTROL . TEST the system for normal operation.
- No: The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test. TEST the system for normal operation.
- Inspect the module connectors for:
- M4 CHECK THE PCM CONNECTION
- Disconnect all the PCM connectors.
- Inspect the module connectors for:
- corrosion.
- pushed-out terminals.
- damaged terminals.
- Connect and correctly seat all the PCM connectors.
- Clear the DTCs.
- Operate the system and verify the concern is still present.
- Is the concern still present?
- Yes: INSTALL a new PCM. TEST the system for normal operation.
- No: The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.