GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2003 🢒 LeSabre 🢒 HVAC 🢒 HVAC Systems - Automatic 🢒 Blower Motor Always On

Test Description

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

  1. This step tests for blower motor operation in the OFF setting.

    2.

  2. This step determines if the instrument panel integration module (IPM) is receiving an OFF request from the HVAC control module.

Step

Action

Value(s)

Yes

No

Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

DEFINITION: The blower motor is ON while the blower motor switch is in the OFF position.

1

Did you perform the HVAC Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Automatic

2
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, perform the Recalibrate all Motors command in Instrument Panel Module Special Functions.
  4. With a scan tool, observe the current DTC list in Instrument Panel Module.

Does the scan tool display any DTCs?

--

Go to Diagnostic Trouble Code (DTC) List

Go to Step 3

3

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

Does the blower motor operate?

--

Go to Step 4

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

4

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 6

Go to Step 5

5
  1. With the scan tool, command the blower motor OFF.
  2. Observe the Commanded Blower parameter.

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

0%

Go to Step 8

Go to Step 9

6

Disconnect the instrument panel integration module (IPM).

Does the blower motor continue to operate?

--

Go to Step 7

Go to Step 9

7

Inspect for poor connections at the harness connector of the blower motor control processor. 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 13

Go to Step 10

8

Inspect for poor connections at the harness connector of the 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 13

Go to Step 11

9

Inspect for poor connections at the harness connector of the IPM. 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 13

Go to Step 12

10

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

Did you complete the replacement?

--

Go to Step 13

--

11

Replace the HVAC control module. Refer to HVAC Control Module Replacement .

Did you complete the replacement?

--

Go to Step 13

--

12

Important: Perform the Recalibration procedure for the IPM.

Replace the IPM. Refer to Instrument Panel Module Replacement in Body Control System.

Did you complete the replacement?

--

Go to Step 13

--

13

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2