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Pinpoint Test C: Externally Controlled Variable Displacement Compressor (EVDC) Performance Check With Or Without DTC (Diagnostic Trouble Code) P06A0

  1. Refer to AUTOMATIC CLIMATE CONTROL SYSTEM for schematic and connector information.

    Normal Operation and Fault Conditions 

    The externally controlled variable displacement compressor is electronically controlled by the PCM. The PCM pulse width modulates the ground to the externally controlled variable displacement compressor to change the displacement of the A/C compressor. REFER to: Climate Control System - System Operation and Component Description .

    DTC Fault Trigger Conditions 

    DTC Description Fault Trigger Condition
    PCM P06A0:00 Variable A/C Compressor Control Circuit: No Sub Type Information This DTC sets when the PCM senses unexpected voltage on the sensor feedback circuit, indicating a short to voltage, an open circuit or an open sensor.

    Possible Sources 

    • Fuse
    • Wiring, terminals or connectors
    • Low refrigerant charge
    • A/C system discharged or low refrigerant charge
    • A/C compressor
    • PCM

    Visual Inspection and Pre-checks 

    • Inspect for loose or corroded A/C compressor connections.
    • Make sure BJB fuse 12 (15A) is OK.
    • Verify the A/C compressor belt is OK.
    • Verify the A/C compressor clutch is engaged/operating.

  2. NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may cause damage to the connector.

  3. C1 EXTERNALLY CONTROLLED VARIABLE DISPLACEMENT COMPRESSOR (EVDC) PERFORMANCE CHECK WITH THE AC COMPRESSOR ELECTRONIC CONTROL VALVE TESTER

    NOTE: Make sure the Air Conditioning (A/C) Compressor clutch is on or is engaged in this step.

    NOTE: Proper Air Conditioning (A/C) system diagnosis on a vehicle's compressor is dependent on correct refrigerant system charge and tested in ambient temperatures above 21.1 deg.C (70 deg.F).

    NOTE: Make sure the EVDC100 Tester, the EVDC101 valve harness module, (and the connector adapter EVDC102, if required) are properly connected per the instruction manual and the operation video.

    • Test the EVDC compressor displacement, following the instructions in the user manual supplied with the Model EVDC®100 A/C Compressor Electronic Control Valve Tester and the EVDC 100 Tester Operation video found on the Ford PTS Home tab, Technical Support Videos.

    Did the suction low side pressure decrease or the high side pressure increase? 

    Yes  The Externally Controlled Variable Displacement Compressor (EVDC) is able to change the displacement. Do not replace the compressor. If DTC P06A0 is present, GO to  C2 If DTC P06A0 is not present, CHECK refrigerant charge amount. REFER to: Refrigerant System Tests - 2.0L EcoBoost (184kW/250PS) - MI4  . REFER to: Refrigerant System Tests - 2.7L EcoBoost (238kW/324PS)  .
    No  If the A/C compressor clutch does not operate, GO to Pinpoint Test L  If the A/C compressor clutch was on or engaged, GO to  C2

  4. C2 CHECK FOR VOLTAGE TO THE A/C (AIR CONDITIONING) COMPRESSOR CONTROL SOLENOID

    • Ignition OFF.

    • Disconnect Externally Controlled Variable Displacement Compressor (EVDC) C1110 .

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C1110-2
      GFD620822Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the voltage greater than 11 volts? 

    Yes  GO to  C3
    No  VERIFY BJB fuse 12 (15A) is OK.If OK, REPAIR the circuit. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short.

  5. C3 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR DISPLACEMENT CONTROL VALVE CIRCUIT FOR A SHORT TO VOLTAGE

    • Ignition OFF.

    • Disconnect PCM C1381B or C1551B .

    • Ignition ON.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C1110-1
      GFD620822Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is any voltage present? 

    Yes  REPAIR the circuit.
    No  GO to  C4

  6. C4 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR DISPLACEMENT CONTROL VALVE CIRCUIT FOR A SHORT TO GROUND

    • Ignition OFF.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C1110-1
      GFD620821Courtesy of FORD MOTOR COMPANY
      		 Ground

    Is the resistance greater than 10,000 ohms? 

    Yes  GO to  C5
    No  REPAIR the circuit.

  7. C5 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR DISPLACEMENT CONTROL VALVE CIRCUIT FOR AN OPEN

    • Measure:

      2.0L 

      Positive Lead Measurement / Action Negative Lead
      C1110-1
      GFD620821Courtesy of FORD MOTOR COMPANY
      		 C1381B-59

      2.7L 

      Positive Lead Measurement / Action Negative Lead
      C1110-1
      GFD620821Courtesy of FORD MOTOR COMPANY
      		 C1551B-79

    Is the resistance less than 3 ohms? 

    Yes  If the Externally Controlled Variable Displacement Compressor (EVDC) is able to change the displacement as tested in step 1, Do Not Replace the compressor. CLEAR the DTC and REPEAT the PCM self-test. If the DTC returns, GO to  C6
    If the Externally Controlled Variable Displacement Compressor (EVDC) is not able to change the displacement as tested in step 1  , CLEAR the DTC and GO to  C7
    No  REPAIR the circuit.

  8. C6 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect all PCM electrical connectors (if not previously disconnected).

    • Repair:

      • corrosion (install new connector or terminal - clean module pins)
      • damaged or bent pins - install new terminals or pins
      • pushed-out pins - install new pins as necessary

    • Connect all PCM electrical 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 service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, Refer to PCM Guided Routine .
    Internet Explorer version 11 or greater is required to perform this Pinpoint Test. 
    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.

  9. C7 CHECK AIR CONDITIONING COMPRESSOR CONNECTOR PINS

    • Ignition OFF.

    • Disconnect and inspect all electrical connectors on the compressor

    • Repair:

      • corrosion (install new connector or terminal - clean module pins)
      • damaged or bent pins - install new terminals or pins
      • pushed-out pins - install new pins as necessary

    • Connect all Compressor electrical 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 service articles: TSB, GSB, SSM or FSA. If a service article exists for this concern, DISCONTINUE this test and FOLLOW the service article instructions. If no service articles address this concern, INSTALL a new A/C compressor. REFER to: Air Conditioning (A/C) Compressor - 2.0L EcoBoost (184kW/250PS) - MI4  . REFER to: Air Conditioning (A/C) Compressor - 2.7L EcoBoost (238kW/324PS)  .
    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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