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Pinpoint Test L: THE NAVIGATION SYSTEM MODULE DOES NOT RESPOND TO THE DIAGNOSTIC TOOL

WARNING: This page is about a different car, the 2005 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.
  1. L1 CHECK THE NAVIGATION SYSTEM MODULE C4209 FOR DAMAGE 
    • Key in OFF position.
    • Disconnect: Navigation System Module C4209.
    • Inspect the navigation system module C4209 for damage.
    • Is the navigation system module C4209 OK? 
    • Yes  : GO to  L2.
    • No  : REPAIR the navigation system module C4209 as necessary. TEST the system for normal operation.
  2. L2 CHECK FOR AN OPEN BETWEEN THE DATA LINK CONNECTOR (DLC) C251 AND THE NAVIGATION SYSTEM MODULE C4209 
    • Measure the resistance between the navigation system module C4209-4, circuit 4-EG17 (GY/BK), harness side and the DLC C251-2, circuit 4-EG7 (GY/RD), harness side.
      Fig 1: Measuring Resistance Between Navigation System Module C4209-4, Circuit 4-EG17 (GY/BK), Harness Side And DLC C251-2, Circuit 4-EG7 (GY/RD), Harness Side
      G03998890Courtesy of FORD MOTOR CO.
    • Measure the resistance between the navigation system module C4209-16, circuit 5-EG17 (BU/YE), harness side and the DLC C251-10, circuit 5-EG7 (BU/RD), harness side.
      Fig 2: Measuring Resistance Between Navigation System Module C4209-16, Circuit 5-EG17 (BU/YE), Harness Side And The DLC C251-10, Circuit 5-EG7 (BU/RD), Harness Side
      G03998891Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : GO to  L9.
    • No  : GO to  L3.
  3. L3 CHECK FOR AN OPEN BETWEEN JOINT CONNECTOR NO. 5 C427 AND THE NAVIGATION SYSTEM MODULE C4209 
    • Disconnect: Joint Connector No. 5 C427.
    • Measure the resistance between the navigation system module C4209-4, circuit 4-EG17 (GY/BK), harness side and joint connector No. 5 C427-4, circuit 4-EG17 (GY/BK), harness side.
      Fig 3: Measuring Resistance Between Navigation System Module C4209-4, Circuit 4-EG17, And Joint connector No. 5 C427-4, Circuit 4-EG17
      G03998892Courtesy of FORD MOTOR CO.
    • Measure the resistance between the navigation system module C4209-16, circuit 5-EG17 (BU/YE), harness side and joint connector No. 5 C427-15, circuit 5-EG17 (BU/YE), harness side.
      Fig 4: Measuring Resistance Between Navigation System Module C4209-16, Circuit 5-EG17 And Joint Connector No. 5 C427-15, Circuit 5-EG17
      G03998893Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : GO to  L4.
    • No  : REPAIR the circuit in question. TEST the system for normal operation.
  4. L4 CHECK JOINT CONNECTOR NO. 5 C427 FOR AN OPEN 
    • Measure the resistance between joint connector No. 5 C427-1, component side and joint connector No. 5 C427-4, component side.
      Fig 5: Measuring The Resistance Between Joint Connector No. 5 C427-1, Component Side And Joint Connector No. 5 C427-4, Component Side
      G03998894Courtesy of FORD MOTOR CO.
    • Measure the resistance between joint connector No. 5 C427-12, component side and joint connector No. 5 C427-15, component side.
      Fig 6: Measuring The Resistance Between Joint Connector No. 5 C427-12, Component Side And Joint Connector No. 5 C427-15, Component Side
      G03998895Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : GO to  L5.
    • No  : REPAIR joint connector No. 5 C427 as necessary. TEST the system for normal operation.
  5. L5 CHECK FOR AN OPEN BETWEEN THE INTERIOR AUXILIARY JUNCTION BOX (AJB) C283B AND JOINT CONNECTOR NO. 5 C427 
    • Disconnect: Interior AJB C283b.
    • Measure the resistance between the interior AJB C283b-8, circuit 4-EG1 (GY/RD), harness side and joint connector No. 5 C427-1, circuit 4-EG1 (GY/RD), harness side.
      Fig 7: Measuring Resistance Between Interior AJB C283b-8, Circuit 4-EG1 (GY/RD), Harness Side And Joint Connector No. 5 C427-1, Circuit 4-EG1 (GY/RD), Harness Side
      G03998896Courtesy of FORD MOTOR CO.
    • Measure the resistance between the interior AJB C283b-4, circuit 5-EG1 (BU/RD), harness side and joint connector No. 5 C427-12, circuit 5-EG1 (BU/RD), harness side.
      Fig 8: Measuring Resistance Between Interior AJB C283b-4, Circuit 5-EG1 (BU/RD), Harness Side And Joint Connector No. 5 C427-12, Circuit 5-EG1 (BU/RD), Harness Side
      G03998897Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : GO to  L6.
    • No  : REPAIR the circuit in question. CARRY OUT the diagnostic tool data link test.
  6. L6 CHECK FOR AN OPEN BETWEEN THE INTERIOR AJB C283B AND THE INTERIOR AJB C283D 
    • Disconnect: Interior AJB C283d.
    • Measure the resistance between the interior AJB C283d-16, component side and the interior AJB C283b-8, component side.
      Fig 9: Measuring The Resistance Between The Interior AJB C283d-16, Component Side And The Interior AJB C283b-8, Component Side
      G03998898Courtesy of FORD MOTOR CO.
    • Measure the resistance between the interior AJB C283d-12, component side and the interior AJB C283b-4, component side.
      Fig 10: Measuring The Resistance Between The Interior AJB C283d-12, Component Side And The Interior AJB C283b-4, Component Side
      G03998897Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : GO to  L7.
    • No  : INSTALL a new interior AJB. TEST the system for normal operation.
  7. L7 CHECK FOR AN OPEN BETWEEN THE INTERIOR AJB C283D AND JOINT CONNECTOR NO. 4 C223 
    • Disconnect: Joint Connector No. 4 C223.
    • Measure the resistance between the interior AJB C283d-16, circuit 4-EG1 (GY/RD), harness side and joint connector No. 4 C223-12, circuit 4-EG1 (GY/RD), harness side.
      Fig 11: Measuring Resistance Between Interior AJB C283d-16, Circuit 4-EG1 (GY/RD), Harness Side And Joint Connector No. 4 C223-12, Circuit 4-EG1 (GY/RD), Harness Side
      G03998900Courtesy of FORD MOTOR CO.
    • Measure the resistance between the interior AJB C283d-12, circuit 5-EG1 (BU/RD), harness side and joint connector No. 4 C223-11, circuit 5-EG1 (BU/RD), harness side.
      Fig 12: Measuring Resistance Between Interior AJB C283d-12, Circuit 5-EG1 (BU/RD), Harness Side And Joint Connector No. 4 C223-11, Circuit 5-EG1 (BU/RD), Harness Side
      G03998901Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : GO to  L8.
    • No  : REPAIR the circuit in question. CARRY OUT the diagnostic tool data link test.
  8. L8 CHECK JOINT CONNECTOR NO. 4 C223 FOR AN OPEN 
    • Measure the resistance between joint connector No. 4 C223-12, component side and joint connector No. 4 C223-14, component side.
      Fig 13: Measuring The Resistance Between Joint Connector No. 4 C223-12, Component Side And Joint Connector No. 4 C223-14, Component Side
      G03998824Courtesy of FORD MOTOR CO.
    • Measure the resistance between joint connector No. 4 C223-9, component side and joint connector No. 4 C223-11, component side.
      Fig 14: Measuring The Resistance Between Joint Connector No. 4 C223-9, Component Side And Joint Connector No. 4 C223-11, Component Side
      G03998825Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    • Yes  : REPAIR the circuit in question between the DLC C251 and joint connector No. 4 C223. CARRY OUT the diagnostic tool data link test.
    • No  : REPAIR joint connector No. 4 C223. TEST the system for normal operation.
  9. L9 CHECK FOR CORRECT NAVIGATION SYSTEM MODULE OPERATION 
    • Disconnect all the navigation system module connectors.
    • Check for:
    • corrosion
    • push-out pins
    • Connect all the navigation system module 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 navigation system module. REFER to NAVIGATION SYSTEM . TEST the system for normal operation.

      CARRY OUT the diagnostic tool data link test.

    • No  : The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. CLEAR the DTCs. REPEAT the self-test.
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