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PINPOINT TEST X : The RFA Module Does Not Respond To The Diagnostic Scan Tool

WARNING: This page is about a different car, the 2017 Lincoln Navigator and 2017 Ford Expedition. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Failure to disconnect the battery when instructed will result in false resistance readings. Refer to Battery, Mounting and Cables .

  1. X1 CHECK THE RFA MODULE VOLTAGE SUPPLY CIRCUITS FOR AN OPEN

    • Ignition OFF.
    • Disconnect: RFA module C4392D .
    • Ignition ON.
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C4392D-1
      GFD134422Courtesy of FORD MOTOR COMPANY
      		 Ground
      C4392D-5
      GFD134422Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the voltages greater than 11 volts? 

    Yes  GO to  X2.
    No  VERIFY the BCM fuses 11 (10A) and 27 (20A) are 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.

  2. X2 CHECK THE RFA MODULE GROUND CIRCUIT FOR AN OPEN

    • Ignition OFF.
    • Disconnect: Negative Battery Cable.
    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C4392A-1
      GFD134423Courtesy of FORD MOTOR COMPANY
      		 Ground
      Positive Lead Measurement / Action Negative Lead
      C4392C-14
      GFD134423Courtesy of FORD MOTOR COMPANY
      		 Ground
      Positive Lead Measurement / Action Negative Lead
      C4392D-3
      GFD134423Courtesy of FORD MOTOR COMPANY
      		 Ground

    Are the resistances less than 3 ohms? 

    Yes  GO to  X3.
    No  REPAIR the circuit in question.

  3. X3 CHECK THE MS-CAN CIRCUITS BETWEEN THE RFA MODULE AND THE DLC FOR AN OPEN

    • Measure:
      Positive Lead Measurement / Action Negative Lead
      C4392C-5
      GFD134423Courtesy of FORD MOTOR COMPANY
      		 C251-3
      C4392C-4
      GFD134423Courtesy of FORD MOTOR COMPANY
      		 C251-11

    Are the resistances less than 3 ohms? 

    Yes  CONNECT the negative battery cable. GO to  X4.
    No  REPAIR the circuit in question. CONNECT the negative battery cable.

  4. X4 CHECK FOR CORRECT RFA MODULE OPERATION

    • Ignition OFF.
    • Disconnect and inspect the RFA module connectors and related in-line connectors.
    • Repair:
      • corrosion (replace connector or terminals - clean module pins)
      • damaged or bent pins - replace terminals/pins
      • pushed-out pins - replace pins as necessary
    • Reconnect the RFA module connectors and related in-line connectors. Make sure they seat and latch correctly.
    • Operate the system and verify the concern is still present.

    Is the concern still present? 

    Yes  CHECK OASIS for any applicable TSBs. If a TSB exists for this concern, discontinue this test and follow TSB instructions. If no TSBs address this concern, INSTALL a new RFA module. REFER to Multifunction Electronic Modules .
    No  The system is operating correctly at this time. Concern may have been caused by a loose or corroded connector.
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