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Pinpoint Test F: The AHCM Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2013 Ford F-550 Super Duty, 2013 Ford F-450 Super Duty, 2013 Ford F-350 Super Duty, and 2013 Ford F-250 Super Duty. 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: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to BATTERY, MOUNTING AND CABLES .
  1. F1 CHECK THE AHCM VOLTAGE SUPPLY CIRCUIT FOR AN OPEN 
    • Disconnect: AHCM C2463B.
    • Ignition ON.
    • Measure the voltage between the AHCM C2463B-1, circuit CBP37 (WH), harness side and ground.
      Fig 1: Measuring Voltage Between AHCM C2463B-1, Circuit CBP37 (WH) And Ground
      G06780431Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    1. Yes  : GO to F2.
    2. No  : VERIFY the Body Control Module (BCM) fuse 37 (10A) is OK. If OK, REPAIR the circuit in question. If not OK, REFER to the OEM ELECTRICAL WIRING DIAGRAM INTRODUCTION to identify the possible causes of the circuit short. CLEAR the DTCs. REPEAT the network test with the scan tool.
  2. F2 CHECK THE AHCM GROUND CIRCUIT FOR AN OPEN 
    • Ignition OFF.
    • Disconnect: Negative Battery Cable.
    • Disconnect: AHCM C2463A.
    • Measure the resistance between the AHCM C2463A-1, circuit GD108 (BK), harness side and ground.
      Fig 2: Measuring Resistance Between AHCM C2463A-1, Circuit GD108 (BK) And Ground
      G07974488Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    1. Yes  : GO to F3.
    2. No  : REPAIR the circuit. CLEAR the DTCs. REPEAT the network test with the scan tool.
  3. F3 CHECK THE HS-CAN CIRCUITS BETWEEN THE AHCM AND THE DLC FOR AN OPEN 
    • Measure the resistance between the AHCM C2463B-3, circuit VDB04 (WH/BU), harness side and the Data Link Connector (DLC) C251-6, circuit VDB04 (WH/BU), harness side.
      Fig 3: Measuring Resistance Between AHCM C2463B-3, Circuit VDB04 (WH/BU) And Data Link Connector (DLC) C251-6, Circuit VDB04 (WH/BU)
      G06780433Courtesy of FORD MOTOR CO.
    • Measure the resistance between the AHCM C2463B-4, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
      Fig 4: Measuring Resistance Between AHCM C2463B-4, Circuit VDB05 (WH) And DLC C251-14, Circuit VDB05 (WH)
      G06780434Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : CONNECT the negative battery cable. GO to F4.
    2. No  : REPAIR the circuit in question. CLEAR the DTCs. REPEAT the network test with the scan tool.
  4. F4 CHECK FOR CORRECT AHCM OPERATION 
    • Disconnect all the AHCM connectors.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect all the AHCM connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    1. Yes  : INSTALL a new AHCM. REFER to CLIMATE CONTROL . CLEAR the DTCs. REPEAT the network test with the scan tool.
    2. 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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