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Pinpoint Test P: 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.
  1. P1 CHECK THE AIR CONDITIONING SWITCH STATUS (CC_SW_AC) FCIM PID WITH THE A/C OFF 
    • Start the engine.
    • Enter the following diagnostic mode on the scan tool: CC_SW_AC FCIM PID.
    • Select PANEL press the A/C button (indicator off) on the HVAC controls.
    • Does the CC_SW_AC FCIM PID read Inactive? 
    • Yes  : For 3.5L only  , GO to P2.

      For 3.5L Gasoline Turbocharged Direct Injection (GTDI) only  , GO to  P4.

    • No  : INSTALL a new FCIM. TEST the system for normal operation.
  2. P2 CHECK THE AIR CONDITIONING COMPRESSOR CYCLING SWITCH (ACCS) PCM PID WITH THE A/C OFF 
    • Enter the following diagnostic mode on the scan tool: ACCS PCM PID.
    • Select PANEL press the A/C button (indicator off) on the HVAC controls.
    • Does the ACCS PCM PID read OFF? 
    • Yes  : GO to  P7.
    • No  : GO to P3.
  3. P3 CHECK THE AIR CONDITIONING COMPRESSOR CYCLING SWITCH (ACCS) PCM PID WITH HVAC MODULE DISCONNECTED 
    • Disconnect: HVAC Module - DATC C2356A.
    • Disconnect: HVAC Module - DATC C2356B.
    • Enter the following diagnostic mode on the scan tool: ACCS PCM PID.
    • Observe the ACCS PCM PID.
    • Does the ACCS PCM PID read OFF? 
    • Yes  : GO to  P6.
    • No  : GO to  P7.
  4. P4 CHECK THE AIR CONDITIONING REQUEST SIGNAL (AC_REQ) PCM PID WITH THE A/C OFF 
    • Enter the following diagnostic mode on the scan tool: AC_REQ PCM PID.
    • Select PANEL press the A/C button (indicator off) on the HVAC controls.
    • Does the AC_REQ PCM PID read OFF? 
    • Yes  : GO to  P7.
    • No  : GO to P5.
  5. P5 CHECK THE AIR CONDITIONING REQUEST SIGNAL (AC_REQ) PCM PID WITH HVAC MODULE DISCONNECTED 
    • Disconnect: HVAC Module - DATC C2356A.
    • Disconnect: HVAC Module - DATC C2356B.
    • Enter the following diagnostic mode on the scan tool: ACCS PCM PID.
    • Observe the AC_REQ PCM PID.
    • Does the AC_REQ PCM PID read OFF? 
    • Yes  : GO to P6.
    • No  : GO to  P7.
  6. P6 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.
  7. P7 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.
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