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Pinpoint Test X: The Temperature Control Is Inoperative Using The Rear Auxiliary Climate Controls

WARNING: This page is about a different car, the 2004 Mercury Mountaineer and 2004 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Carry out this test only if the front auxiliary climate control assembly temperature control operates correctly.
  1. X1 CHECK CIRCUIT 1127 (YE) FOR AN OPEN 
    • Disconnect: Front Auxiliary Climate Control Assembly C938a.
    • Disconnect: Rear Auxiliary Climate Control Assembly C3198b.
    • Measure the resistance between the front auxiliary climate control assembly C938a-8, circuit 1127 (YE) and the rear auxiliary climate control assembly C3198b-3, circuit 1127 (YE).
      Fig 1: Checking Circuit 1127 (YE) For Open
      G03182846Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 

    Yes 

    GO to X2.

    No 

    REPAIR circuit 1127 (YE). TEST the system for normal operation.

  2. X2 CHECK THE REAR AUXILIARY CLIMATE CONTROL ASSEMBLY 

    Yes 

    INSTALL a new front auxiliary climate control assembly. REFER to AUXILIARY CLIMATE CONTROL ASSEMBLY - FRONT . TEST the system for normal operation.

    No 

    INSTALL a new rear auxiliary climate control assembly. REFER to AUXILIARY CLIMATE CONTROL ASSEMBLY - REAR . TEST the system for normal operation.