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Models Without Sunroof

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  1. Perform SYSTEM OPERATION CHECK  under TROUBLE SHOOTING. Go to next step.
  2. Turn ignition on. Place the I/P HVAC control assembly to the rear position. Place the front auxiliary HVAC control assembly blower control in the OFF position. Place the rear auxiliary HVAC control assembly blower control in the OFF position. Is the auxiliary blower motor off? If so, go to next step. If not, go to TEST E: BLOWER MOTOR ALWAYS ON (AUXILIARY) .
    3. NOTE: This step tests for auxiliary blower motor that does not operate from the front auxiliary HVAC control assembly regardless of the desired blower motor speed.
  3. Place the front auxiliary control assembly blower control in each mode position. Does the auxiliary blower motor operate at all? If so, go to next step. If not, go to TEST G: BLOWER MOTOR INOPERATIVE (AUXILIARY) .
    4. NOTE: This step tests for a auxiliary blower motor that operates, yet does not accurately respond to the desired blower motor speed from the front auxiliary HVAC control assembly.
  4. Does the auxiliary blower motor operate correctly for each mode position? If so, go to next step. If not, go to TEST I: BLOWER MOTOR MALFUNCTION (AUXILIARY) .
    5. NOTE: This step tests for auxiliary blower motor that does not operate from the rear auxiliary HVAC control assembly regardless of the desired blower motor speed.
  5. Place the front auxiliary HVAC control assembly blower control in the rear control position. Place the rear auxiliary HVAC control assembly blower control in each mode position. Does the auxiliary blower motor operate at all? If so, go to next step. If not, go to TEST G: BLOWER MOTOR INOPERATIVE (AUXILIARY) .
    6. NOTE: This step tests for a auxiliary blower motor that operates, yet does not accurately respond to the desired blower motor speed from the rear auxiliary HVAC control assembly.
  6. Does the auxiliary blower motor operate correctly for each mode position? If so, go to next step. If not, go to TEST I: BLOWER MOTOR MALFUNCTION (AUXILIARY) .
    7. NOTE: This step tests for an inoperative auxiliary mode actuator in one mode positions or in the wrong mode positions from either auxiliary HVAC control assemblies.
  7. Do either auxiliary HVAC control assemblies operate correctly in any mode position? If so, go to next step. If not, go to step  23.
  8. Place the front auxiliary HVAC control assembly blower control in the HIGH position. Place the front auxiliary HVAC control assembly mode control in each mode position. Does the auxiliary mode actuator operate correctly for each mode position? If so, go to next step. If not, go to step  10.
  9. Place the front auxiliary HVAC control assembly blower control in the REAR CONTROL position. Place the rear auxiliary HVAC control assembly blower control in the HIGH position. Place the rear auxiliary HVAC control assembly mode control in each mode position. Does the auxiliary mode actuator operate correctly for each mode position? If so, check for intermittent and poor connections. If not, go to next step.
  10. Check the front auxiliary HVAC control assembly ignition 3 voltage circuit or an open, or a high resistance. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
  11. Check the HVAC control processor (auxiliary) ignition 3 voltage circuit for an open, or a high resistance. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
  12. Check the auxiliary mode actuator ignition 3 voltage circuit for an open or a high resistance. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
  13. Check the front auxiliary HVAC control assembly ground circuit for an open. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
  14. Check the HVAC control processor (auxiliary) ground circuit for an open. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
  15. Check the auxiliary mode actuator ground circuit for an open. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
  16. Measure the voltage from the mode signal auxiliary front circuit at the rear HVAC programer to ground. Place the front auxiliary HVAC control assembly mode control in each mode position. Does the voltage measure less than 12 volts in each mode position? If so, go to next step. If not, go to step  20.
  17. Does the voltage measure near zero volts in each mode position? If so, go to step  21. If not, go to step  26.
  18. Place the front auxiliary HVAC control assembly blower control in the rear control position. Measure the voltage from the mode signal auxiliary rear circuit at the rear HVAC programer to ground. Place the rear auxiliary HVAC control assembly mode control in each mode position. Does the voltage measure less than 12 volts in each mode position? If so, go to next step. If not, go to step  22.
  19. Does the voltage measure near zero volts in each mode position? If so, go to step  23. If not, go to step  27.
  20. Check the mode signal auxiliary front circuit for a short to voltage. Did you find and correct the condition? If so, go to step  35. If not, go to step  26.
  21. Check the mode signal auxiliary front circuit for an open, a high resistance or a short to ground. Did you find and correct the condition? If so, go to step  35. If not, go to step  26.
  22. Check the mode signal auxiliary rear circuit for a short to voltage. Did you find and correct the condition? If so, go to step  35. If not, go to step  27.
  23. Check the mode signal auxiliary rear circuit for an open, a high resistance or a short to ground. Did you find and correct the condition? If so, go to step  35. If not, go to step  27.
  24. Check the mode door control auxiliary circuit for a short to voltage. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
  25. Check the mode door control auxiliary circuit for an open, a high resistance or a short to ground. Did you find and correct the condition? If so, go to step  35. If not, go to step  28.
  26. Inspect the front auxiliary HVAC control assembly harness connector for poor connections. Did you find and correct the condition? If so, go to step  35. If not, go to step  31.
  27. Inspect front auxiliary HVAC control assembly harness connector or poor connections. Did you find and correct the condition? If so, go to step  35. If not, go to step  31.
  28. Inspect HVAC control processor (auxiliary) harness connector for poor connections. Did you find and correct the condition? If so, go to step  35. If not, go to step  33.
  29. Inspect auxiliary mode actuator harness connector for poor connections. Did you find and correct the condition? If so, go to step  35. If not, go to next step.
    30. NOTE: This step tests for an incorrectly installed auxiliary mode actuator, damaged attaching linkages. Any mechanical repairs will not require the auxiliary mode actuator to be replaced.
  30. Check the auxiliary mode actuator, door and any attaching linkage for any binding. Inspect the duct work for any debris that would prevent air to flow through the duct work. Did you find and correct the condition? If so, go to step  35. If not, go to step  34.
  31. Replace the front auxiliary HVAC control assembly. See HVAC CONTROL ASSEMBLY (FRONT AUXILIARY)  under REMOVAL & INSTALLATION. After repairs are complete, go to step  35.
  32. Replace the HVAC control assembly (auxiliary) rear. See HVAC CONTROL ASSEMBLY (FRONT AUXILIARY)  under REMOVAL & INSTALLATION. After repairs are complete, go to step  35.
  33. Replace the HVAC control processor (auxiliary). See HVAC CONTROL PROCESSOR (AUXILIARY)  under REMOVAL & INSTALLATION. After repairs are complete, go to step  35.
  34. Replace the mode actuator (auxiliary). See MODE ACTUATOR (AUXILIARY)  under REMOVAL & INSTALLATION. After repairs are complete, go to next step.
  35. Operate the system in order to verify the repair. Did you correct the condition? If so, system is okay. If not, go to step  2.
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