Auxiliary Blower Motor Always On W/O Sunroof
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
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This step tests for auxiliary blower motor operation in the OFF setting.
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This step tests for a possible short to ground in the auxiliary blower motor control module control circuit.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: HVAC Schematics DEFINITION: The auxiliary blower motor is ON while the auxiliary HVAC controls are in the OFF position. | ||||
1 | Did you review the auxiliary HVAC operation and perform the necessary inspections? | -- | Go to Step 2 | |
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Important: The rear auxiliary HVAC control module will only function if the front auxiliary HVAC control module is placed in the REAR position.
Does the auxiliary blower motor operate in the OFF position? | -- | Go to Step 3 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | |
3 |
Important: Place the front auxiliary HVAC control module in the REAR position. Place the rear auxiliary HVAC control module in the OFF position. Place the MODE selector in any position except AUTO. Failure to do this may result in a misdiagnosis.
Is the auxiliary blower motor PWM parameter at the specified value? | 0% | Go to Step 4 | Go to Step 11 |
4 | Disconnect the rear auxiliary HVAC control module. Is the blower motor operating? | -- | Go to Step 6 | Go to Step 5 |
5 |
Is the blower motor operating at the specified value? | 14% | Go to Step 10 | Go to Step 8 |
Test the rear auxiliary blower motor control module control circuit for a short to ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 15 | Go to Step 7 | |
7 | Test the blower motor supply circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 12 |
8 | Test the low reference circuit between the front auxiliary control module and the rear auxiliary control module for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 9 |
9 | Test the 5 volt reference circuit between the front auxiliary control module and the rear auxiliary control module for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 11 |
10 | Inspect for poor connections at the harness connector of the front auxiliary HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 13 |
11 | Inspect for poor connections at the harness connector of the rear HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 14 |
12 | Inspect for poor connections at the harness connector of the auxiliary blower motor control module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 16 | Go to Step 15 |
13 | Replace the front auxiliary HVAC control module. Refer to Auxiliary Heater and Air Conditioning Control Replacement - Front . Did you complete the replacement? | -- | Go to Step 16 | -- |
14 | Replace the rear HVAC control module. Refer to Auxiliary Heater and Air Conditioning Control Replacement - Front . Did you complete the replacement? | -- | Go to Step 16 | -- |
15 | Replace the auxiliary blower motor control module. Refer to Auxiliary Blower Motor Processor Replacement . Did you complete the replacement? | -- | Go to Step 16 | -- |
16 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 |
