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July 1: So it begins. Don't worry, this is not in the correct legal jurisdiction!

Pinpoint Test O: 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 Instrument Cluster (IC) DTCs.
  1. O1 CHECK THE AIR CONDITIONING REQUEST SIGNAL (AC_REQ) PCM PID WITH THE A/C OFF 
    • Ignition ON.
    • 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 module.
    • Does the AC_REQ PCM PID read YES? 
    • Yes:  If the vehicle is  equipped with navigation, GO to  O3.

      If the vehicle is not  equipped with navigation, GO to O2.

    • No:  GO to  O6.
  2. O2 CHECK THE AIR CONDITIONING SWITCH STATUS (CC_SW_AC) HVAC PID WITH THE A/C OFF 
    • 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 module.
    • Does the CC_SW_AC HVAC PID read Inactive? 
    • Yes:  GO to  O6.
    • No:  GO to  O5.
  3. O3 CHECK THE A/C INDICATOR WITH THE A/C OFF 
    NOTE: Before carrying out this test step, be sure all other FCIM button functions are operational. If all other buttons operate correctly, continue with this test step. If multiple buttons are inoperative and DTC U0256:00 is not present, install a new FCIM. Test the system for normal operation. If DTC U0256:00 is present, diagnose the DTC first.
    • Select PANEL press the A/C button (indicator off) on the HVAC module.
    • Does the A/C indicator turn off when the A/C button is pressed? 
    • Yes:  GO to  O5.
    • No:  GO to O4.
  4. O4 CHECK THE MAX A/C OPERATION 
    NOTE: Before carrying out this test step, be sure all other ACM touch screen functions are operational. If all other touch screen functions operate correctly, continue with this test step. If multiple touch screen functions are inoperative and DTC U0163:00 is not present, install a new ACM. Test the system for normal operation. If DTC U0163:00 is present, diagnose the DTC first.
    • Select MAX A/C on the next generation navigation screen.
    • Does the A/C turn off when MAX A/C is selected? 
    • Yes:  INSTALL a new FCIM. TEST the system for normal operation.
    • No:  GO to O5.
  5. O5 CHECK THE 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.
  6. O6 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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