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Inspection and Verification

WARNING: This page is about a different car, the 2007 Ford Ranger. However, it is still accessible from the selected car via links, so may be relevant.
  1. Verify the customer concern.
  2. Visually inspect the following for obvious signs of electrical damage.
    VISUAL INSPECTION CHART

    Electrical
    • Battery junction box (BJB) fuse(s):
      • 17 (40A) (no communication with anti-lock brake system [ABS] module)
      • 21 (10A) (no communication with powertrain control module [PCM])
      • 27 (20A) (no communication with four wheel drive [4WD] control module)
      • 33 (30A) (no communication with ABS module)
      • 39 (15A) (no communication with PCM)
    • Smart junction box (SJB) fuse(s):
      • 8 (10A) (no communication with restraints control module [RCM])
      • 9 (5A) (no communication with instrument cluster)
      • 10 (10A) (no communication with instrument cluster, 4WD control module)
      • 11 (10A) (no communication with SJB)
      • 20 (10A) (no communication with ABS module)
      • 28 (15A) (no power to the 4WD control module)
      • 29 (20A) (no power to the scan tool)
      • 33 (5A) (no communication with instrument cluster)
    • Data link connector (DLC)
    • Circuitry
  3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step.
  4. NOTE: Make sure to use the latest scan tool software release.
    NOTE: The vehicle communication module (VCM) LED prove-out confirms power and ground from the DLC are provided to the VCM.
  5. If the cause is not visually evident, connect the scan tool to the DLC.

    If the scan tool does not communicate with the VCM: 

    • Check the VCM connection to the vehicle.
    • Check the scan tool connection to the VCM.
    • Go to Pinpoint Test H , to diagnose no power to the scan tool.
  6. NOTE: During the network test, the scan tool will first attempt to communicate with the PCM, after establishing communication with the PCM, the scan tool will then attempt to communicate with all other modules on the vehicle.
  7. Carry out the network test:
    • If the network test passes, retrieve and record the continuous memory DTCs and proceed to Step 6.
    • If the network test fails, go to Symptom Chart  to identify the module not communicating.
  8. If the DTCs retrieved are related to the concern, go to the Communication Network Diagnostic Trouble Code (DTC) Index. For all other DTCs, refer to MULTIFUNCTION ELECTRONIC MODULES article.
  9. If no DTCs related to the concern are retrieved, go to Symptom Chart .
    NOTE: DTC U1900 will set in a module that is reporting a communication fault from another module on the data bus. The module that reports the fault is not the problem module.
    COMMUNICATION NETWORK DIAGNOSTIC TROUBLE CODES (DTC) INDEX

    DTC Description Source Action
    U0002 High Speed CAN Communication Bus Performance Instrument cluster Go to Pinpoint Test E .
    U0100 Lost Communication With ECM/PCM 4WD Module Smart junction box (SJB) CLEAR the DTC. REPEAT the network test with the scan tool. FOLLOW the appropriate pinpoint test for the module which fails the network test.
    U1900 CAN Communication Bus Fault - Receive Error Occupant classification sensor module Go to Symptom Chart  for module that failed network test.
    U1900 CAN Communication Bus Fault - Receive Error RCM Go to Symptom Chart  for module that failed network test.
    U1900 CAN Communication Bus Fault - Receive Error SJB Go to Symptom Chart  for module that failed network test.
    U2023 Fault Received From External Node SJB RETRIEVE and FOLLOW non-network DTCs from other modules. REFER to MULTIFUNCTION ELECTRONIC MODULES article.
    U2023 Fault Received From External Node Instrument cluster RETRIEVE and FOLLOW non-network DTCs from other modules. REFER to MULTIFUNCTION ELECTRONIC MODULES article.
    U2023 Fault Received From External Node 4WD control module RETRIEVE and FOLLOW non-network DTCs from other modules. REFER to MULTIFUNCTION ELECTRONIC MODULES article.