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Pinpoint Test N: The Air Conditioning (A/C) Is Always On - A/C Mode Always Commanded On

WARNING: This page is about a different car, the 2012 Ford Pickup, 2012 Ford F550 Super Duty, 2012 Ford F450 Super Duty, and 2012 Ford Cab & Chassis. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Before carrying out the following test, diagnose any HVAC, PCM or IC DTCs first.
  1. N1 CHECK THE A/C SWITCH STATUS (CC_SW_AC) HVAC PID WITH THE A/C OFF 
    • Ignition ON.
    • Enter the following diagnostic mode on the scan tool: CC_SW_AC HVAC PID.
    • Select PANEL press the A/C button (indicator off) on the HVAC controls.
    • Does the CC_SW_AC HVAC PID read OFF? 
    • Yes  : GO to N2.
    • No  : GO to  N4.
  2. N2 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 NO? 
    • Yes  : GO to  N5.
    • No  : GO to N3.
  3. N3 CHECK THE AIR CONDITIONING REQUEST SIGNAL (AC_REQ) PCM PID WITH HVAC MODULE DISCONNECTED 
    • Ignition OFF.
    • Disconnect: HVAC Module C228.
    • Ignition ON.
    • Enter the following diagnostic mode on the scan tool: AC_REQ PCM PID.
    • Observe the AC_REQ PCM PID.
    • Does the AC_REQ PCM PID read NO? 
    • Yes  : GO to N4.
    • No  : GO to  N5.
  4. N4 CHECK THE HVAC MODULE CONNECTION 
    • Inspect the HVAC 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.
  5. N5 CHECK THE PCM CONNECTION 
    • Disconnect all the PCM connectors.
    • Inspect the HVAC 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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