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Pinpoint Test I: The Driver Seat Module (DSM) Does Not Respond To The Diagnostic Tool

WARNING: This page is about a different car, the 2004 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.

Test Step 

  1. I1 CHECK THE DSM 341c FOR DAMAGE 
    • Key in OFF position.
    • Disconnect: DSM C341c.
    • Inspect the DSM C341 c for damage.
    • Is the DSM C341c OK? 

    Result / Action to Take 

    1. Yes  : GO to I2.
    2. No  : REPAIR the DSMC341cas necessary. TEST the system for normal operation.
  2. I2 CHECK FOR AN OPEN BETWEEN THE DLC C251 AND THE DSM 341c 
    • Measure the resistance between the DSM C341c-1, circuit 4-AH80 (GY/WH), harness side and the DLC C251 -2, circuit 4-EG7 (GY/RD), harness side.
      Fig 1: Checking For Open Between DLC C251 And DSM 341C (1 Of 2)
      G03203004Courtesy of FORD MOTOR CO.
    • Measure the resistance between the DSM C341c-9, circuit 5-AH80 (BU/OG), harness side and the DLC C251 -10, circuit 5-EG7 (BU/RD), harness side.
      Fig 2: Checking For Open Between DLC C251 And DSM 341C (2 Of 2)
      G03203005Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : GO to  I7.
    2. No  : GO to I3.
  3. I3 CHECK FOR AN OPEN BETWEEN THE INTERIOR AJB C283a AND THE DSM 341c 
    • Disconnect: Interior AJB C283a.
    • Measure the resistance between the DSM C341c-1, circuit 4-AH80 (GY/WH), harness side and the interior AJB C283a-16, circuit 4-AH80 (GY/WH), harness side.
      Fig 3: Checking For Open Between Interior AJB C283A And DSM 341C (1 Of 2)
      G03203006Courtesy of FORD MOTOR CO.
    • Measure the resistance between the DSM C341c-9, circuit 5-AH80 (BU/OG), harness side and the interior AJB C283a-12, circuit 5-AH80 (BU/OG), harness side.
      Fig 4: Checking For Open Between Interior AJB C283A And DSM 341C (2 Of 2)
      G03203007Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : GO to I4.
    2. No  : Repair the circuit in question. TEST the system for normal operation.
  4. I4 CHECK FOR AN OPEN BETWEEN THE INTERIOR AJB C283a AND THE INTERIOR AJB C283d 
    • Disconnect: Interior AJB C293d.
    • Measure the resistance between the interior AJB C283a-16, component side and the interior AJB C283d-16, component side.
      Fig 5: Checking For Open Between Interior AJB C283A Interior AJB C283D (1 Of 2)
      G03203008Courtesy of FORD MOTOR CO.
    • Measure the resistance between the interior AJB C283a-12, component side and the interior AJB C283d-12, component side.
      Fig 6: Checking For Open Between Interior AJB C283A Interior AJB C283D (2 Of 2)
      G03203009Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : GO to I5.
    2. No  : INSTALL a new AJB. TEST the system for normal operation.
  5. I5 CHECK FOR AN OPEN BETWEEN THE INTERIOR AJB C283d AND JOINT CONNECTOR No. 4 C223 
    • Disconnect: Interior 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 7: Checking For Open Between Interior AJB C283D And Joint Connector No. 4 C223 (1 Of 2)
      G03203010Courtesy 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 8: Checking For Open Between Interior AJB C283D And Joint Connector No. 4 C223 (2 Of 2)
      G03203011Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : GO to I6.
    2. No  : REPAIR the circuit in question. CARRY OUT the PINPOINT TEST PC: data link diagnostics network test .
  6. I6 CHECK JOINT CONNECTOR No. 4 FOR AN OPEN BETWEEN 
    • Measure the resistance between joint connector No. 4 C223-12, component side and joint connector No. 4 C223-14, component side.
      Fig 9: Checking Joint Connector No. 4 For An Open (1 Of 2)
      G03203012Courtesy 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 10: Checking Joint Connector No. 4 For An Open (2 Of 2)
      G03203013Courtesy of FORD MOTOR CO.
    • Are the resistances less than 5 ohms? 
    1. Yes  : REPAIR the circuit in question between the DLC C251 and joint connector No. 4 C223. CARRY OUT the PINPOINT TEST PC: data link diagnostics network test .
    2. No  : REPAIR joint connector No. 4 C223. TEST the system for normal operation.
  7. I7 CHECK FOR CORRECT DSM OPERATION 
    • Disconnect all the DSM connectors.
    • Check for:
      • corrosion
      • push-out pins
    • Connect all the DSM connectors and make sure they seat correctly.
    • Operate the system and verify the concern is still present.
    • Is the concern still present? 
    1. Yes  : INSTALL a new DSM. REFER to DRIVER SEAT MODULE (DSM) . TEST the system for normal operation.

      CARRY OUT the PINPOINT TEST PC: data link diagnostics network test .

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