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Pinpoint Test W: The Temperature Control Does Not Operate Using The Front/Rear Auxiliary Climate Controls

  1. W1 CHECK THE FRONT AUXILIARY TEMPERATURE CONTROL OPERATION 
    • Key in ON position.
    • Place the front auxiliary blower motor switch in the HI position.
    • Rotate the front auxiliary temperature control switch from COOL to WARM.
    • Does the front temperature control operate correctly? 
    • Yes  : GO to W2.
    • No  : GO to W8.
  2. W2 TEST THE REAR AUXILIARY TEMPERATURE CONTROL OPERATION 
    • Place the front auxiliary blower motor switch in the REAR position.
    • Place the rear auxiliary blower motor switch in the HI position.
    • Rotate the rear auxiliary temperature control switch from COOL to WARM.
    • Does the rear temperature control operate correctly? 
    • Yes  : System is OK.
    • No  : GO to W3.
  3. W3 CHECK CIRCUIT 1127 (YE) 
    • Key in OFF position.
    • Disconnect: Rear Auxiliary Temperature Control Switch C990d.
    • Disconnect: Auxiliary Climate Control Module C3005.
    • Measure the resistance between rear auxiliary temperature control switch C990d pin 2, circuit 1127 (YE) and auxiliary climate control module C3005 pin 9, circuit 1127 (YE); and between auxiliary climate control module C3005 pin 9, circuit 1127 (YE) and ground.
      Fig 1: Checking Circuit 1127 (YE)
      G03910263Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms between the rear auxiliary temperature control switch and the auxiliary climate control module, and greater than 10,000 ohms between the auxiliary climate control module and ground? 
    • Yes  : GO to W4.
    • No  : REPAIR circuit 1127 (YE). TEST the system for normal operation.
  4. W4 CHECK THE REAR AUXILIARY TEMPERATURE CONTROL CIRCUIT 1124 (WH) 
    • Disconnect: Auxiliary Blend Door Actuator C356.
    • Measure the resistance between rear auxiliary temperature control switch C990d pin 1, circuit 1124 (WH) and auxiliary blend door actuator C3004 pin 4, circuit 1124 (WH).
      Fig 2: Measuring Resistance Between Rear Auxiliary Temperature Control Switch C990D Pin 1 And Auxiliary Blend Door Actuator C3004 Pin 4
      G03910246Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : GO to W5.
    • No  : REPAIR circuit 1124 (WH). TEST the system for normal operation.
  5. W5 CHECK THE REAR AUXILIARY TEMPERATURE CONTROL CIRCUIT 1125 (BN) 
    • Measure the resistance between rear auxiliary temperature control switch C990d pin 3, circuit 1125 (BN) and auxiliary blend door actuator C3004 pin 6, circuit 1125 (BN).
      Fig 3: Measuring Resistance Between Rear Auxiliary Temperature Control Switch C990D Pin 3 And Auxiliary Blend Door Actuator C3004 Pin 6
      G03910245Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : GO to W6.
    • No  : REPAIR circuit 1125 (BN). TEST the system for normal operation.
  6. W6 CHECK THE REAR AUXILIARY TEMPERATURE CONTROL SWITCH 
    • Measure the resistance between rear auxiliary temperature control switch C990d pin 1 and pin 3, component side.
      Fig 4: Measuring Resistance Between Rear Auxiliary Temperature Control Switch C990D Pin 1 And Pin 3, Component Side
      G03910247Courtesy of FORD MOTOR CO.
    • Is the resistance between 4,000 and 6,000 ohms? 
    • Yes  : GO to W7.
    • No  : INSTALL a new rear auxiliary temperature control switch. refer to AUXILIARY CLIMATE CONTROL . TEST the system for normal operation.
  7. W7 CHECK THE REAR AUXILIARY TEMPERATURE CONTROL SWITCH WIPER 
    • Measure the resistance between the rear auxiliary temperature control switch pin 1 and pin 2, component side, while rotating the rear auxiliary temperature control switch.
      Fig 5: Measuring Resistance Between Rear Auxiliary Temperature Control Switch Pin 1 And Pin 2, Component Side
      G03910248Courtesy of FORD MOTOR CO.
    • Does the resistance vary? 
    • Yes  : INSTALL a new auxiliary climate control module. TEST the system for normal operation.
    • No  : INSTALL a new rear auxiliary temperature control switch. refer to AUXILIARY CLIMATE CONTROL . TEST the system for normal operation.
  8. W8 CHECK THE REAR AUXILIARY TEMPERATURE CONTROL OPERATION 
    • Place the front auxiliary blower motor switch in the REAR position.
    • Place the rear auxiliary blower motor switch in the HI position.
    • Rotate the rear auxiliary temperature control switch from COOL to WARM.
    • Does the rear temperature control operate correctly? 
    • Yes  : GO to W9.
    • No  : GO to W14.
  9. W9 CHECK CIRCUIT 1122 (RD) 
    • Key in OFF position.
    • Disconnect: Front Auxiliary Temperature Control Switch C989d.
    • Disconnect: Auxiliary Climate Control Module C3005.
    • Measure the resistance between front auxiliary temperature control switch C989d pin 2, circuit 1122 (RD) and auxiliary climate control module C3005 pin 5, circuit 1122 (RD); and between auxiliary climate control module C3005 pin 5, circuit 1122 (RD) and ground.
      Fig 6: Checking Circuit 1122 (RD)
      G03910268Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms between the front auxiliary temperature control switch and the auxiliary climate control module, and greater than 10,000 ohms between the auxiliary climate control module and ground? 
    • Yes  : GO to W10.
    • No  : REPAIR circuit 1122 (RD). TEST the system for normal operation.
  10. W10 CHECK THE FRONT AUXILIARY TEMPERATURE CONTROL CIRCUIT 1124 (WH) 
    • Disconnect: Auxiliary Blend Door Actuator C356.
    • Measure the resistance between front auxiliary temperature control switch C989d pin 1, circuit 1124 (WH) and auxiliary blend door actuator C3004 pin 4, circuit 1124 (WH).
      Fig 7: Measuring Resistance Between Front Auxiliary Temperature Control Switch C989D Pin 1 And Auxiliary Blend Door Actuator C3004 Pin 4
      G03910246Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : GO to W11.
    • No  : REPAIR circuit 1124 (WH). TEST the system for normal operation.
  11. W11 CHECK THE FRONT AUXILIARY TEMPERATURE CONTROL CIRCUIT 1125 (BN) 
    • Measure the resistance between front auxiliary temperature control switch C989d pin 3, circuit 1125 (BN) and auxiliary blend door actuator C3004 pin 6, circuit 1125 (BN).
      Fig 8: Measuring Resistance Between Front Auxiliary Temperature Control Switch C989D Pin 3 And Auxiliary Blend Door Actuator C3004 Pin 6
      G03910245Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : GO to W12.
    • No  : REPAIR circuit 1125 (BN). TEST the system for normal operation.
  12. W12 CHECK THE FRONT AUXILIARY TEMPERATURE CONTROL SWITCH 
    • Measure the resistance between the front auxiliary temperature control switch pin 1 and pin 3, component side.
      Fig 9: Measuring Resistance Between Front Auxiliary Temperature Control Switch Pin 1 And Pin 3, Component Side
      G03910247Courtesy of FORD MOTOR CO.
    • Is the resistance between 4,000 and 6,000 ohms? 
    • Yes  : GO to W13.
    • No  : INSTALL a new front auxiliary temperature control switch. refer to AUXILIARY CLIMATE CONTROL . TEST the system for normal operation.
  13. W13 CHECK THE FRONT AUXILIARY TEMPERATURE CONTROL SWITCH WIPER 
    • Measure the resistance between the front auxiliary temperature control switch pin 1 and pin 2, component side.
      Fig 10: Measuring Resistance Between Front Auxiliary Temperature Control Switch Pin 1 And Pin 2, Component Side
      G03910248Courtesy of FORD MOTOR CO.
    • Does the resistance vary? 
    • Yes  : INSTALL a new auxiliary climate control module. TEST the system for normal operation.
    • No  : INSTALL a new front auxiliary temperature control switch. refer to AUXILIARY CLIMATE CONTROL . TEST the system for normal operation.
  14. W14 CHECK THE VOLTAGE TO THE AUXILIARY BLEND DOOR ACTUATOR 
    • Key in OFF position.
    • Disconnect: Auxiliary Blend Door Actuator C3004.
    • Key in ON position.
    • Measure the voltage between auxiliary blend door actuator C3004 pin 7, circuit 295 (LB/PK) and ground.
      Fig 11: Measuring Voltage Between Auxiliary Blend Door Actuator C3004 Pin 7, Circuit 295 (LB/PK) And Ground
      G03910254Courtesy of FORD MOTOR CO.
    • Is the voltage greater than 10 volts? 
    • Yes  : GO to W15.
    • No  : REPAIR circuit 295 (LB/PK). TEST the system for normal operation.
  15. W15 CHECK CIRCUIT 57 (BK) 
    • Key in OFF position.
    • Measure the resistance between auxiliary blend door actuator C3004 pin 8, circuit 57 (BK) and ground.
      Fig 12: Measuring Resistance Between Auxiliary Blend Door Actuator C3004 Pin 8, Circuit 57 (BK) And Ground
      G03910255Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms? 
    • Yes  : GO to W16.
    • No  : REPAIR circuit 57 (BK). TEST the system for normal operation.
  16. W16 CHECK CIRCUIT 1126 (LB) 
    • Disconnect: Auxiliary Climate Control Module C3005.
    • Measure the resistance between auxiliary climate control module C3005 pin 2, circuit 1126 (LB) and auxiliary blend door actuator C3004 pin 3, circuit 1126 (LB); and between auxiliary blend door actuator C3004 pin 3, circuit 1126 (LB), and ground.
      Fig 13: Checking Circuit 1126 (LB)
      G03910275Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms between the auxiliary climate control module and the auxiliary blend door actuator, and greater than 10,000 ohms between the auxiliary blend door actuator and ground? 
    • Yes  : GO to W17.
    • No  : REPAIR circuit 1126 (LB). TEST the system for normal operation.
  17. W17 CHECK CIRCUIT 1124 (WH) 
    • Disconnect: Front Auxiliary Temperature Control Switch C989d.
    • Disconnect: Rear Auxiliary Temperature Control Switch C990d.
    • Measure the resistance between auxiliary blend door actuator C3004 pin 4, circuit 1124 (WH) and rear auxiliary temperature control switch C990d pin 1, circuit 1124 (WH); and between auxiliary blend door actuator C3004 pin 4, circuit 1124 (WH) and ground.
      Fig 14: Checking Circuit 1124 (WH)
      G03910258Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms between the auxiliary blend door actuator and the rear auxiliary temperature control switch, and greater than 10,000 ohms between the auxiliary blend door actuator and ground? 
    • Yes  : GO to W18.
    • No  : REPAIR circuit 1124 (WH). TEST the system for normal operation.
  18. W18 CHECK CIRCUIT 1125 (BN) 
    • Measure the resistance between auxiliary blend door actuator C3004 pin 6, circuit 1125 (BN) and rear auxiliary temperature control switch C990d pin 3, circuit 1125 (BN); and between auxiliary blend door actuator C3004 pin 6, circuit 1125 (BN) and ground.
      Fig 15: Checking Circuit 1125 (BN)
      G03910257Courtesy of FORD MOTOR CO.
    • Is the resistance less than 5 ohms between the auxiliary blend door actuator and the rear auxiliary temperature control switch, and greater than 10,000 ohms between the auxiliary blend door actuator and ground? 
    • Yes  : GO to W19.
    • No  : REPAIR circuit 1125 (BN). TEST the system for normal operation.
  19. W19 CHECK CIRCUIT 1127 (YE) FOR A SHORT 
    • Measure the resistance between auxiliary climate control module C3005 pin 9, circuit 1127 (YE) and ground.
      Fig 16: Measuring Resistance Between Auxiliary Climate Control Module C3005 Pin 9, Circuit 1127 (YE) And Ground
      G03910278Courtesy of FORD MOTOR CO.
    • Is the resistance greater than 10,000 ohms? 
    • Yes  : GO to W20.
    • No  : REPAIR circuit 1127 (YE). TEST the system for normal operation.
  20. W20 CHECK CIRCUIT 1122 (RD) FOR A SHORT 
    • Measure the resistance between auxiliary climate control module C3005 pin 5, circuit 1122 (RD) and ground.
      Fig 17: Measuring Resistance Between Auxiliary Climate Control Module C3005 Pin 5, Circuit 1122 (RD) And Ground
      G03910279Courtesy of FORD MOTOR CO.
    • Is the resistance greater than 10,000 ohms? 
    • Yes  : GO to W21.
    • No  : REPAIR circuit 1122 (RD). TEST the system for normal operation.
  21. W21 CHECK THE AUXILIARY BLEND DOOR ACTUATOR - 12 VOLTS 
    • Connect: Auxiliary Blend Door Actuator C3004.
    • Key in ON position.
    • Place the front auxiliary blower motor switch in the HI position.
    • Connect a fused jumper lead between auxiliary climate control module C3005 pin 8, circuit 295 (LB/PK) and pin 2, circuit 1126 (LB).
      Fig 18: Connecting Fused Jumper Lead Between Auxiliary Climate Control Module C3005 Pin 8, Circuit 295 (LB/PK) And Pin 2, Circuit 1126 (LB)
      G03910280Courtesy of FORD MOTOR CO.
    • Does the auxiliary blend door actuator operate? 
    • Yes  : INSTALL a new auxiliary climate control module. TEST the system for normal operation.
    • No  : GO to W22.
  22. W22 CHECK THE AUXILIARY BLEND DOOR ACTUATOR - 0 VOLTS 
    • Connect a fused jumper lead between auxiliary climate control module C3005 pin 2, circuit 1126 (LB) and pin 6, circuit 57 (BK).
      Fig 19: Connecting Fused Jumper Lead Between Auxiliary Climate Control Module C3005 Pin 2, Circuit 1126 (LB) And Pin 6, Circuit 57 (BK)
      G03889961Courtesy of FORD MOTOR CO.
    • Does the auxiliary blend door actuator operate? 
    • Yes  : INSTALL a new auxiliary climate control module. TEST the system for normal operation.
    • No  : INSPECT for a binding, stuck or broken blend door or linkage. If no condition is found, INSTALL a new auxiliary blend door actuator. refer to AUXILIARY CLIMATE CONTROL . TEST the system for normal operation.
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