Test Description

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The number(s) below refer to the step number(s) on the diagnostic table.

2: This step will determine if one or more blower speeds are inoperative.
3: This step tests for a voltage change in the auxiliary blower motor feed circuit.
4: This step tests for an open in one of the blower motor speed control circuits and the auxiliary HVAC control switch ground circuits.

Blower Motor Malfunction - Auxiliary (W/Sunroof or Heat Only)

Step	Action	Yes	No
Schematic Reference: HVAC Schematics DEFINITION: The auxiliary blower motor operates in at least one, but not all, speed positions.
1	Did you review the auxiliary HVAC operation and perform the necessary inspections?	Go to Step 2	Go to SYMPTOM TESTS - HVAC SYMPTOMS - MANUAL
2	Turn ON the ignition, with the engine OFF. Place the auxiliary blower motor switch in each speed position. Does the auxiliary blower motor operate in each speed position?	Go to TESTING FOR INTERMITTENT AND POOR CONNECTIONS	Go to Step 3
3	Turn OFF the ignition. Disconnect the auxiliary blower motor connector. Turn ON the ignition, with the engine OFF. Connect a test lamp between the auxiliary blower motor supply circuit and the auxiliary blower motor ground circuit. Place the auxiliary blower motor switch in each speed position. Does the test lamp illuminate and change intensity in each speed position?	Go to Step 7	Go to Step 4
4	IMPORTANT: The auxiliary blower motor switch must be in the correct position for the auxiliary blower motor speed control circuit being tested. Failure to do this will result in a misdiagnosis. Turn OFF the ignition. Disconnect the auxiliary blower motor resistor assembly connector C1. Probe each auxiliary blower motor speed control circuit with a test lamp that is connected to battery positive voltage. Place the auxiliary blower motor switch in each speed position for the auxiliary blower motor speed control circuit being tested. Does the test lamp illuminate in each position?	Go to Step 8	Go to Step 5
5	Test the appropriate auxiliary blower motor speed control circuit for an open. Refer to CIRCUIT TESTING and WIRING REPAIRS . Did you find and correct the condition?	Go to Step 12	Go to Step 6
6	Inspect for poor connections at the harness connector of the 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 12	Go to Step 9
7	Inspect for poor connections at the harness connector of the auxiliary blower motor. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS . Did you find and correct the condition?	Go to Step 12	Go to Step 10
8	Inspect for poor connections at the harness connectors of the auxiliary blower motor resistor assembly. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS . Did you find and correct the condition?	Go to Step 12	Go to Step 11
9	Replace the auxiliary HVAC control assembly. Refer to HVAC CONTROL ASSEMBLY - FRONT AUXILIARY (FRONT OVERHEAD CONTROL A/C ONLY) or HVAC CONTROL ASSEMBLY - FRONT AUXILIARY (FRONT OVERHEAD CONTROL HEAT & A/C) or HVAC CONTROL ASSEMBLY - REAR AUXILIARY . Did you complete the replacement?	Go to Step 12	-
10	Replace the auxiliary blower motor. Refer to BLOWER MOTOR - AUXILIARY . Did you complete the replacement?	Go to Step 12	-
11	Replace the auxiliary blower motor resistor assembly. Refer to BLOWER MOTOR RESISTOR - AUXILIARY . Did you complete the replacement?	Go to Step 12	-
12	Operate the system in order to verify the repair. Did you correct the condition?	System OK	Go to Step 2