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Test Description

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The numbers below refer to thew step numbers on the diagnostic table.

  1. 2:  This step ensures that the primary HVAC system is functioning properly.
  2. 5:  If the condition does not occur when an A/C request has been made then you must bypass the A/C performance test procedures.
  3. 6:  Performing the Air Conditioning System Performance Test ensures that the A/C system is operating properly for further testing.
Too Hot in Vehicle - Auxiliary (w/ Sunroof)

Step Action Values Yes No
Schematic Reference:  HVAC Schematics  
DEFINITION: Auxiliary air temperature cannot be adjusted or auxiliary cooling is insufficient.
1 Did you review the HVAC operation and perform the necessary inspections? - Go to Step 2  Go to Diagnostic System Check - HVAC Systems - Automatic 
2 
IMPORTANT: The front auxiliary HVAC control assembly cannot request A/C compressor operation. An A/C request must be generated by the HVAC control module to provide cooled airflow through the auxiliary system.
Does the HVAC control module operate and provide sufficient cooling?		 - Go to Step 3  Go to Too Hot in Vehicle 
3
  1. Turn ON the ignition, with the engine OFF.
  2. Place the A/C auxiliary blower motor switch in each speed position.
Does the auxiliary blower motor operate at all?		 - Go to Step 4  Go to Blower Motor Inoperative - Auxiliary (W/O Sunroof) Blower Motor Inoperative - Auxiliary (W/Sunroof or Heat Only) 
4 Does the auxiliary blower motor operate correctly for each speed position? - Go to Step 5  Go to Blower Motor Malfunction - Auxiliary (W/O Sunroof) Blower Motor Inoperative - Auxiliary (W/Sunroof or Heat Only) 
5  Does the Auxiliary Too Hot In Vehicle concern occur when A/C cooling is desired? - Go to Step 6  Go to Step 7 
6  Perform the Air Conditioning System Performance Test. Refer to A/C SYSTEM PERFORMANCE TEST .
Did you find and correct the condition?		 - Go to Step 18  Go to Step 7 
7
  1. Observe the drive shaft of the auxiliary air temperature actuator.
  2. Adjust the auxiliary air temperature switch.
Does the auxiliary air temperature actuator drive shaft rotate at all?		 - Go to Step 8  Go to Step 9 
8 Inspect the auxiliary air temperature door and the auxiliary air temperature actuator for the following conditions:
  • Misaligned auxiliary air temperature actuator. Refer to AIR TEMPERATURE ACTUATORS - AUXILIARY .
  • Broken or binding linkages or auxiliary air temperature door
  • Obstruction that prevents the auxiliary air temperature door from operating within it's full range of motion
  • Missing seals to the auxiliary air temperature door
  • Misaligned seals to the auxiliary air temperature door

Did you find and correct the condition?		 - Go to Step 18  Go to TESTING FOR INTERMITTENT AND POOR CONNECTIONS
9 Test the ignition 3 voltage circuit of the auxiliary air temperature actuator for an open or a high resistance. Refer to CIRCUIT TESTING and WIRING REPAIRS .
Did you find and correct the condition?		 - Go to Step 18  Go to Step 10 
10 Test the ground circuit of the auxiliary air temperature actuator for an open. Refer to CIRCUIT TESTING and WIRING REPAIRS .
Did you find and correct the condition?		 - Go to Step 18  Go to Step 11 
11 Test the temperature door control circuit of the auxiliary air temperature actuator for an open, a high resistance, short to ground or short to voltage. Refer to CIRCUIT TESTING and WIRING REPAIRS .
Did you find and correct the condition?		 - Go to Step 18  Go to Step 12 
12
IMPORTANT: The front auxiliary HVAC control assembly connector must be connected to correctly perform test.
  1. Turn ON the ignition, with the engine OFF.
  2. Measure the voltage from the auxiliary temperature door control circuit of the auxiliary air temperature actuator to a good ground.
  3. Adjust the auxiliary air temperature switch.
Does the voltage change and measure within the specified range?		 0-12 V Go to Step 13  Go to Step 15 
13 Inspect for poor connections at the harness connector of the auxiliary air temperature actuator. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS .
Did you find and correct the condition?		 - Go to Step 18  Go to Step 14 
14 Inspect the auxiliary air temperature actuator, door and any attaching linkage for binding or a condition that prevents drive shaft rotation
Did you find and correct the condition?		 - Go to Step 18  Go to Step 16 
15 Inspect for poor connections at the harness connector of the front auxiliary HVAC control assembly. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS .
Did you find and correct the condition?		 - Go to Step 18  Go to Step 17 
16 Replace the auxiliary air temperature actuator. Refer to AIR TEMPERATURE ACTUATORS - AUXILIARY .
Did you complete the replacement?		 - Go to Step 18  -
17 Replace the front auxiliary HVAC control assembly. Refer to HVAC Control Assembly Replacement - Front Auxiliary .
Did you complete the replacement?		 - Go to Step 18  -
18 Operate the system in order to verify the repair.
Did you correct the condition?		 - System OK Go to Step 2 
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