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Pinpoint Test A: The Pcm Does Not Respond To The Scan Tool

WARNING: This page is about a different car, the 2011 Ford Taurus. 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, BATTERY MOUNTING & BATTERY CABLES Article.
NOTE: Most faults are due to connector and/or wiring concerns. Carry out a thorough inspection and verification before proceeding with the Pinpoint Test.
  1. A1 VERIFY WHETHER OTHER HS-CAN MODULES PASS THE NETWORK TEST 
    • Enter the following diagnostic mode on the scan tool: Network Test.
    • In the LH pane of the Integrated Diagnostic System (IDS) network test display screen, verify whether any HS-CAN modules passed the network test.
    • Is the text "pass" or a DTC listed next to any of the following modules (if equipped): 4X4 control module, ABS module, APIM, C-CM, HUD module, IPC, OCSM, PAM, PCM, PSCM, RFA module or RCM? 
    • Yes  : If "pass" or a DTC was listed next to the PCM, a network fault is not currently present. GO to PINPOINT TEST AE  to diagnose an intermittent HS-CAN fault condition.

      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-CAN. GO to PINPOINT TEST AD  to diagnose no HS-CAN communication.
  2. A2 PC/ED PINPOINT TEST QA VERIFICATION 
  3. A3 CHECK THE HS-CAN TERMINATION RESISTANCE 
    • Ignition OFF.
    • Disconnect: Negative Battery Cable.
    • Disconnect the scan tool from the DLC.
    • Measure the resistance between the DLC C251-6, circuit VDB04 (WH/BU), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
      Fig 1: Measuring Resistance Between Dlc C251-6, Circuit VDB04 (WH/BU) And DLC C251-14, Circuit VDB05 (WH)
      G06065430Courtesy of FORD MOTOR CO.
    • Is the resistance between 54 and 66 ohms? 
    • Yes  : GO to  A6.
    • No  : For 3.5L engine, GO to A4.

      For 3.5L GTDI engine, GO to  A5.

  4. A4 CHECK THE HS-CAN CIRCUITS BETWEEN THE PCM AND THE DLC FOR AN OPEN - 3.5L 
    • Disconnect: PCM C175b.
    • Measure the resistance between the PCM C175b-2, circuit VDB04 (WH/BU), harness side and the DLC C251-6, circuit VDB04 (WH/BU), harness side.
      Fig 2: Measuring Resistance Between PCM C175B-2, Circuit VDB04 (WH/BU) And DLC C251-6, Circuit VDB04 (WH/BU)
      G06065431Courtesy of FORD MOTOR CO.
    • Measure the resistance between the PCM C175b-3, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
      Fig 3: Measuring Resistance Between PCM C175B-3, Circuit VDB05 (WH) And DLC C251-14, Circuit VDB05 (WH)
      G06065432Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : CONNECT the negative battery cable. GO to  A6.
    • No  : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
  5. A5 CHECK THE HS-CAN CIRCUITS BETWEEN THE PCM AND THE DLC FOR AN OPEN - 3.5L GTDI 
    • Disconnect: PCM C1381b.
    • Measure the resistance between the PCM C1381b-59, circuit VDB04 (WH/BU), harness side and the DLC C251-6, circuit VDB04 (WH/BU), harness side.
      Fig 4: Measuring Resistance Between PCM C1381B-59, Circuit VDB04 (WH/BU) And DLC C251-6, Circuit VDB04 (WH/BU)
      G06099301Courtesy of FORD MOTOR CO.
    • Measure the resistance between the PCM C1381b-58, circuit VDB05 (WH), harness side and the DLC C251-14, circuit VDB05 (WH), harness side.
      Fig 5: Measuring Resistance Between PCM C1381B-58, Circuit VDB05 (WH) And DLC C251-14, Circuit VDB05 (WH)
      G06099302Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : CONNECT the negative battery cable. GO to A6.
    • No  : REPAIR the circuit in question. CONNECT the negative battery cable. CLEAR the DTCs. REPEAT the network test with the scan tool.
  6. A6 CHECK FOR CORRECT PCM OPERATION 
    • Disconnect all the PCM connectors.
    • Check for:
      • corrosion
      • damaged pins
      • pushed-out pins
    • Connect all the PCM connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    • Yes  : INSTALL a new PCM. REFER to ENGINE CONTROLS - ELECTRONIC ENGINE CONTROLS Article. CLEAR the DTCs. REPEAT the network test with the scan tool.
    • No  : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector.