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

  1. X1 CHECK VOLTAGE TO BLEND DOOR ACTUATOR 
    • Disconnect: Auxiliary Temperature Blend Door Actuator C3004.
    • Key in ON position.
    • Measure the voltage between the auxiliary temperature blend door actuator C3004-7, circuit 294 (WH/LB) and ground.
      Fig 1: Checking Voltage To Blend Door Actuator
      G03945129Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes  : GO to X2.
    • No  : REPAIR circuit 294 (WH/LB). TEST the system for normal operation.
  2. X2 CHECK THE BLEND DOOR ACTUATOR GROUND CIRCUIT 
    • Key in OFF position.
    • Measure the resistance between the front auxiliary climate control assembly C989b-9, circuit 57 (BK) and ground.
      Fig 2: Checking Blend Door Actuator Ground Circuit
      G03961643Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : GO to X3.
    • No  : REPAIR circuit 57 (BK). TEST the system for normal operation.
  3. X3 CHECK THE TEMPERATURE BLEND DOOR ACTUATOR SIGNAL 
    • Key in ON position.
    • Place the front auxiliary blower motor switch in HI.
    • Measure the voltage between the auxiliary temperature blend door actuator C3004-3, circuit 1126 (LB) and ground. Rotate the temperature control switch to full COOL then to full WARM.
      Fig 3: Checking Temperature Blend Door Actuator Signal
      G03945131Courtesy of FORD MOTOR CO.
    • Does the voltage vary from greater than 10 volts (full COOL) to less than 1 volt (full WARM)? 
    • Yes  : INSTALL a new auxiliary temperature blend door actuator. TEST the system for normal operation.
    • No  : GO to X4.
  4. X4 CHECK CIRCUIT 1126 (LB) 
    • Key in OFF position.
    • Disconnect: Front Auxiliary Climate Control Assembly C989b.
    • Measure the resistance between the front auxiliary climate control assembly C989b-3, circuit 1126 (LB) and the auxiliary temperature blend door actuator C3004-3, circuit 1126 (LB).
      Fig 4: Checking Circuit 1126 (LB)
      G03945132Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : INSTALL a new front auxiliary climate control assembly. TEST the system for normal operation.
    • No  : REPAIR circuit 1126 (LB). TEST the system for normal operation.
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