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Pinpoint Test G : The A/C (Air Conditioning) Is Inoperative

WARNING: This page is about a different car, the 2015 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.
NOTE: Some PCM Diagnostic Trouble Codes (DTCs) may inhibit A/C operation. If any PCM Diagnostic Trouble Codes (DTCs) are retrieved, diagnose those first. Refer to the PCM DTC chart .

  1. G1 CHECK THE A/C (AIR CONDITIONING) SYSTEM PRESSURE

    • Ignition OFF.
    • With the appropriate manifold gauge set connected, check the A/C system pressure.

    Is the A/C system pressure above 290 kPa (42 psi)? 

    Yes  GO to  G2
    No  CHECK the A/C system for leaks. REFER to: Electronic Leak Detection . REFER to: Fluorescent Dye Leak Detection . After the leak is repaired, RECHARGE the A/C system. REFER to: Air Conditioning (A/C) System Recovery, Evacuation and Charging .

  2. G2 CHECK THE COMMUNICATION NETWORK

    • Ignition ON.
    • Using a diagnostic scan tool, carry out the network test.

    Do the FCIM and the PCM pass the network test? 

    Yes  GO to  G3
    No  DIAGNOSE the FCIM or PCM does not communicate with the diagnostic scan tool. REFER to: Communications Network .

  3. G3 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) PRESSURE SENSOR (ACP_PRESS) PID (PARAMETER IDENTIFICATION)

    • Ignition ON.
    • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
    • With the manifold gauge set connected, compare the pressure readings of the manifold gauge set and the PCM ACP_PRESS PID.

    Are the pressure values of the manifold gauge set and the ACP_PRESS PCM PID within ± 103 kPa (15 psi)? 

    Yes  GO to  G4
    No  DIAGNOSE the A/C pressure transducer. GO to PINPOINT TEST A : P0532, P0533 

  4. G4 ELECTRIC COOLING FAN FUNCTIONAL CHECK

    • Ignition ON.
    • Using a diagnostic scan tool, carry out the PCM KOEO self-test.

    Does the electric cooling fan operate during the KOEO self-test? 

    Yes  GO to  G5
    No  DIAGNOSE the electric cooling fan operation. REFER to ENGINE CONTROLS - SYMPTOM CHARTS (EXCEPT DIESEL & HYBRID) .

  5. G5 COMPARE THE PCM (POWERTRAIN CONTROL MODULE) INTAKE AIR TEMPERATURE (IAT) PID (PARAMETER IDENTIFICATION) AND THE OTHER TEMPERATURE SENSOR READINGS TO THE PCM (POWERTRAIN CONTROL MODULE) AMBIENT AIR TEMPERATURE (AAT) PID (PARAMETER IDENTIFICATION)

    NOTE: Compare multiple engine sensor readings to the ambient temperature to determine sensors are reading correctly. A faulty sensor can cause the PCM to disable the A/C with or without a DTC.

    • Allow the vehicle exterior and interior to stabilize to ambient temperature. This can take a soak period of at least 6 hours.
    • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
    • Monitor the CHT, ECT, IAT, MAPT, and AAT Parameter Identifications (PIDs) (as applicable).

    Are the temperature values similar (typically within 18 °C (32.4 °F)? 

    Yes  GO to  G6
    No  DIAGNOSE the suspect temperature sensor. REFER to ENGINE CONTROLS - SYMPTOM CHARTS (EXCEPT DIESEL & HYBRID) .

  6. G6 COMPARE THE FCIM (FRONT CONTROLS INTERFACE MODULE) EVAPORATOR TEMPERATURE (EVAP_TEMP) PID (PARAMETER IDENTIFICATION) TO THE PCM (POWERTRAIN CONTROL MODULE) AMBIENT AIR TEMPERATURE (AAT) PID (PARAMETER IDENTIFICATION)

    • Ignition OFF.
    • Allow the vehicle exterior and interior to stabilize to ambient temperature.
    • Ignition ON.
    • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
    • Monitor and record the PCM AAT PID.
    • Using a diagnostic scan tool, view the FCIM Parameter Identifications (PIDs).
    • Monitor and record the FCIM (EVAP_TEMP) PID.

    Are the temperature values similar (typically within 18 °C (32.4 °F)? 

    Yes  GO to  G7
    No  GO to PINPOINT TEST L : B1B71:11, B1B71:15 

  7. G7 VERIFY THE GRILLE SHUTTER OPERATION USING THE PCM (POWERTRAIN CONTROL MODULE) GRILL SHUTTER A POSITION - COMMANDED (GRILL_A_CMD) PID (PARAMETER IDENTIFICATION)

    • Start the engine and allow it to idle for at least 30 seconds to allow for the grille shutter calibration to complete.
    • Using a diagnostic scan tool, view PCM PID.
    • Using a diagnostic scan tool, select the PCM PID GRILL_A_CMD and command the grille shutter from 100% (open) to 0% (closed) while observing the grille shutter operation from the front of the vehicle.

    Does the grille shutter fully open and close when commanded by the scan tool? 

    Yes  GO to  G8
    No  DIAGNOSE the active grille shutter is inoperative or does not operate correctly. REFER to: Active Grille Shutter .

  8. G8 CHECK THE FCIM (FRONT CONTROLS INTERFACE MODULE) A/C (AIR CONDITIONING) SWITCH (CC_SW_AC) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) ON

    • Using a diagnostic scan tool, view FCIM Parameter Identifications (PIDs).
    • Monitor the CC_SW_AC PID.
    • On the HVAC controls, select PANEL and then press the A/C button (indicator on).

    Does the PID display Active or On when the A/C button is pressed? 

    Yes  GO to  G9
    No  GO to  G17

  9. G9 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) ON

    • Start the engine.
    • Using a diagnostic scan tool, monitor the PCM AC_REQ PID.
    • On the HVAC controls, select PANEL and then press the A/C button (indicator on).

    Does the PID display Yes when the button is pressed? 

    Yes  GO to  G11
    No  GO to  G10

  10. G10 RESET THE AMBIENT AIR TEMPERATURE (AAT) SENSOR

    • On the HVAC controls, press the A/C and Recirc buttons simultaneously, then release both. Within 2 seconds press A/C button again.
    • Start the engine.
    • On the HVAC controls, set the temperature to full cold, select PANEL and select the A/C button (indicator on).

    Does the A/C compressor turn on? 

    Yes  RETEST the A/C system for normal operation. CARRY OUT the refrigerant system tests. REFER to: Refrigerant System Tests - 2.7L EcoBoost (238kW/324PS) . REFER to: Refrigerant System Tests - 3.5L EcoBoost (272kW/370PS) . REFER to: Refrigerant System Tests - 3.5L Duratec (209kW/284PS) . REFER to: Refrigerant System Tests - 5.0L 32V Ti-VCT .
    No  GO to  G11

  11. G11 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) COMPRESSOR COMMANDED STATE (ACC_CMD) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) COMMANDED ON

    • Using a diagnostic scan tool, activate the PCM ACC_CMD PID.

    Does the A/C compressor turn on? 

    Yes  GO to  G18
    No  GO to  G12

  12. G12 CHECK THE VOLTAGE TO THE A/C (AIR CONDITIONING) CLUTCH RELAY

    • Ignition OFF.
    • Disconnect the A/C clutch relay.
    • Ignition ON.
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      A/C clutch relay socket 1
      GFD38392Courtesy of FORD MOTOR COMPANY
      		 Ground
      A/C clutch relay socket 3
      GFD38392Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the voltages greater than 11 volts? 

    Yes  GO to  G13
    No  VERIFY BJB fuses 44 (10A) and 97 (10A) are OK. If not OK, REFER to the OEM WIRING DIAGRAMS to identify the possible causes of the circuit short. If OK, REPAIR the circuit.

  13. G13 BYPASS THE A/C (AIR CONDITIONING) CLUTCH RELAY

    • Ignition OFF.
    • Connect a fused jumper wire:
      Positive Lead Measurement / Action Negative Lead
      A/C clutch relay socket 3
      GFD38977Courtesy of FORD MOTOR COMPANY
      		 A/C clutch relay socket 5
    • Ignition ON.

    Does the A/C compressor clutch engage? 

    Yes  REMOVE the fused jumper wire. INSTALL a new A/C clutch relay.
    No  LEAVE the fused jumper wire installed. GO to  G14

  14. G14 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL VOLTAGE SUPPLY CIRCUIT FOR AN OPEN

    • Disconnect A/C compressor clutch field coil C100 .
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C100-1
      GFD38392Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the voltage greater than 11 volts? 

    Yes  REMOVE the fused jumper wire. GO to  G15
    No  REMOVE the fused jumper wire. REPAIR the circuit.

  15. G15 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL GROUND CIRCUIT FOR AN OPEN

    • Ignition OFF.
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C100-2
      GFD38391Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance less than 3 ohms? 

    Yes  GO to  G16
    No  REPAIR the circuit.

  16. G16 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH AIR GAP

    Is the A/C compressor clutch air gap greater than 0.6 mm (0.0236 in)? 

    Yes  ADJUST the A/C compressor clutch air gap. REFER to: Air Conditioning (A/C) Clutch Air Gap Adjustment .
    No  INSTALL a new A/C compressor clutch field coil. REFER to: Air Conditioning (A/C) Clutch and Air Conditioning (A/C) Clutch Field Coil 

  17. G17 CHECK FOR CORRECT FCIM (FRONT CONTROLS INTERFACE MODULE) OPERATION

    • Ignition OFF.
    • Disconnect and inspect all FCIM connectors.
    • Repair:
      • corrosion (install new connector or terminals - clean module pins)
      • damaged or bent pins - install new terminals/pins
      • pushed-out pins - install new pins as necessary
    • Reconnect all FCIM connectors. Make sure they seat and latch correctly.
    • Operate the system and determine if the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new FCIM. Refer to the appropriate article for the procedure.
    No  The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

  18. G18 CHECK THE PCM (POWERTRAIN CONTROL MODULE) PARAMETER IDENTIFICATIONS (PIDS)

    NOTE: The PCM can disable the A/C due to multiple inputs.

    • Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
      NOTE: Not all PIDs are available for all engines.
    • Monitor the following PCM Parameter Identifications (PIDs):
      Scan Tool Display Condition detected by the PCM that caused the A/C clutch to not engage
      AC_DISBLE_TRQ Air Conditioning Compressor is being disabled due to Insufficient engine torque
      ACC_F (A/C) clutch output fault detected
      AC_INHIBIT_00 A/C Clutch Engagement is inhibited because strategy has not yet detected hardware that indicates vehicle is equipped with A/C
      AC_INHIBIT_01 A/C Clutch Engagement is inhibited because the strategy is operating in Ignition System Failure Mode
      AC_INHIBIT_02 A/C Clutch Engagement is inhibited because the (ECU) received a Request to Command the A/C Off
      AC_INHIBIT_03 A/C Clutch Engagement is inhibited because the engine has not yet reached a stable running mode after starting
      AC_INHIBIT_04 A/C Clutch Engagement is inhibited because the A/C Discharge (Head) Pressure is Too High
      AC_INHIBIT_05 A/C Clutch Engagement is inhibited because the Engine Coolant Temperature is Too High
      AC_INHIBIT_06 A/C Clutch Engagement is inhibited to Prevent Frost and Ice Build Up on the Evaporator
      AC_INHIBIT_07 A/C Clutch Engagement is inhibited to Prevent an Engine Stall during a Low Engine Speed condition
      AC_INHIBIT_08 A/C Clutch Engagement is inhibited to Protect the Compressor from a Compressor Over-speed condition
      AC_INHIBIT_09 A/C Clutch Engagement is inhibited to temporarily make more power available when Accelerator Pedal is Fully Depressed
      AC_INHIBIT_10 A/C Clutch Engagement is inhibited because Low A/C Refrigerant Charge has been detected
      AC_INHIBIT_11 A/C Clutch Engagement is inhibited to Protect the Compressor from Operating at Too Low of an Ambient Temperature
      AC_INHIBIT_12 A/C Clutch Engagement is inhibited due to Missing Climate Control Message
      AC_INHIBIT_13 A/C Clutch Engagement is inhibited because the strategy is operating in Failsafe Cooling Mode
      AC_INHIBIT_14 A/C Clutch Engagement is inhibited to Protect the Clutch from Damage because the Compressor Load and Speed are Too High
      AC_INHIBIT_15 A/C Clutch Engagement is inhibited by the off portion of the A/C Cycling Strategy invoked to manage High Engine Temperature
      AC_INHIBIT_16 A/C Clutch Engagement is inhibited due to Low Battery State of Charge
      AC_INHIBIT_17 A/C Clutch Engagement is inhibited to Protect the Variable Displacement Compressor from Operating at Too Low of a Temperature
      AC_INHIBIT_18 A/C Clutch Engagement is inhibited to improve Brake Booster Vacuum
      AC_INHIBIT_19 A/C Clutch Engagement is inhibited because Evaporator Temperature is sufficiently low and compressor was at minimum displacement
      AC_INHIBIT_20 A/C Clutch Engagement is inhibited (Disabled) because the Evaporator Temperature is sufficiently below the target temperature
      AC_INHIBIT_21 A/C Clutch Engagement is inhibited to satisfy A/C Clutch minimum off time
      AC_INHIBIT_22 A/C Clutch Engagement is inhibited Due to Request from Torque Control Strategy (to Temporarily Make More Power Available)
      AC_INHIBIT_23 A/C Clutch Engagement is inhibited to Prevent Engine Stalling
      AC_INHIBIT_24 A/C Clutch Engagement is inhibited Due to Request to Disable A/C from Stop-Start Strategy
      AC_INHIBIT_25 A/C Clutch Engagement is inhibited (Delayed) to make Power Available for Power Steering
      AC_INHIBIT_26 A/C Clutch Engagement Is Inhibited Due To State Of Auxiliary A/C Disable (Typically A Pressure Or Temperature) Switch 1 input
      AC_INHIBIT_27 A/C Clutch Engagement is inhibited due to state of auxiliary A/C Disable (Typically a Pressure or Temperature) Switch 2 input

    Are any PCM Parameter Identifications (PIDs) showing YES or YES Fault? 

    Yes  DIAGNOSE the condition found to be disabling the A/C clutch per the chart above.
    No  GO to  G19

  19. G19 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION

    • Ignition OFF.
    • Disconnect and inspect all PCM connectors.
    • Repair:
      • corrosion (replace connector or terminals - clean module pins)
      • damaged or bent pins - replace terminals/pins
      • pushed-out pins - replace pins as necessary
    • Reconnect all PCM connectors. Make sure they seat and latch correctly.
    • Operate the system and verify the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM. For 2.7L EcoBoost (238kW/324PS), REFER to: POWERTRAIN CONTROL MODULE (PCM) . For 3.5L EcoBoost (272kW/370PS), REFER to: POWERTRAIN CONTROL MODULE (PCM) . For 3.5L Duratec (209kW/284PS), REFER to: POWERTRAIN CONTROL MODULE (PCM) . For 5.0L 32V Ti-VCT, REFER to: POWERTRAIN CONTROL MODULE (PCM) .
    No  The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.
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