GM Service Manual Online
For 1990-2009 cars only

Step

Action

Values

Yes

No

Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

DEFINITION: The blower motor operates with the HVAC controls in the OFF position.

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn the ignition ON, with the engine OFF.
  2. Turn OFF the HVAC controls.

Does the blower motor turn OFF?

--

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

With the scan tool observe the Commanded Blower parameter in the Instrument Panel Module data list.

Does the scan tool indicate that the Commanded Blower parameter is near the specified value?

0%

Go to Step 4

Go to Step 8

4

Disconnect the HVAC control module (IPM).

Does the blower motor operate in any of the speed positions?

--

Go to Step 5

Go to Step 8

5

Inspect the blower motor housing for a short to ground. Refer to Testing for Short to Ground in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 6

6

Visually inspect the blower motor harness for a short to ground. Refer to Wiring Repairs in Wiring Systems. Refer to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 7

7

Inspect for poor connections at the harness connector of the blower motor control processor. Refer to Wiring Repairs and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 9

8

Inspect for poor connections at the harness connector of the IPM. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 11

Go to Step 10

9

Replace the blower motor control processor. Refer to Blower Motor Control Processor Replacement .

Did you complete the replacement?

--

Go to Step 11

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10

Replace the IPM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

--

Go to Step 11

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11

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2