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Pinpoint Test A : The Powertrain Control Module (Pcm) Does Not Respond To The Diagnostic Scan Tool

WARNING: This page is about a different car, the 2019 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.
  1. Refer to Module Communications Network for schematic and connector information. Refer to Electronic Engine Controls - 2.3L for schematic and connector information.

    Normal Operation and Fault Conditions 

    The PCM communicates with the diagnostic scan tool through the HS-CAN1.

    Possible Sources 

    • Fuse
    • Wiring, terminals and connectors
    • PCM

  2. A1 VERIFY WHETHER OTHER HS-CAN1 (HIGH-SPEED CONTROLLER AREA NETWORK 1) MODULES PASS THE NETWORK TEST

    • Using a diagnostic scan tool, perform the network test.

    Is the text "pass" or a DTC listed next to any of the following modules (if equipped): APIM, BECMB, BCM, DC/ DC converter control module, PAM or PCM? 

    Yes  If "pass" or a DTC was listed next to the PCM, a network fault is not currently present. If "pass" or a DTC was listed next to one or more modules other than the PCM, GO to  A2
    No  No modules are currently communicating on the HS-CAN1. GO to Pinpoint Test X 

  3. A2 ENGINE CONTROLS PINPOINT TEST QA VERIFICATION CHECK

    • Verify Engine Controls pinpoint test QA has been performed.

    Has pinpoint test QA been performed? 

    Yes  GO to  A3
    No  Refer to Engine Controls - Pinpoint Tests (Except Diesel & Hybrid) .

  4. A3 CHECK THE HS-CAN1 (HIGH-SPEED CONTROLLER AREA NETWORK 1) TERMINATION RESISTANCE

    • Ignition OFF.

    • Disconnect GWM C2431.

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C2431-20
      GFD433171Courtesy of FORD MOTOR COMPANY
      		 C2431-19

    Is the resistance between 108 and 132 ohms? 

    Yes  GO to  A5
    No  GO to  A4

  5. A4 CHECK THE HS-CAN1 (HIGH-SPEED CONTROLLER AREA NETWORK 1) CIRCUITS BETWEEN THE PCM (POWERTRAIN CONTROL MODULE) AND THE GWM (GATEWAY MODULE A) FOR AN OPEN

    • Disconnect PCM C175B.

    • Disconnect GWM C2431.

    Are the resistances less than 3 ohms? 

    Yes  GO to  A5
    No  REPAIR the circuit in question.

  6. A5 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION

    • Ignition OFF.

    • Disconnect and inspect all the PCM 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 the PCM 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, General Service Bulletin (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 .
    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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