GM Service Manual Online
For 1990-2009 cars only

Step

Action

Values

Yes

No

1

Verify the customer's complaint.

Are the customer's concerns verified?

--

Go to Step 2

System OK

2

Inspect the blower.

Does the blower run at any speed?

--

System OK

Go to Step 3

3

  1. Disconnect the power connector from the blower motor under the dashboard on the passenger side of the vehicle.
  2. Using an ohmmeter, check the resistance between the one terminal of the blower motor connector and each step with the blower switch place each position.

Does the ohmmeter show the specified value of the each position?

Refer to Heating, Ventilation and Air Conditioning

Go to Step 4

Go to Step 5

4

Replace the blower motor.

Is the repair complete?

--

System OK

Go to Step 7

5

Inspect the fuse Ef6.

Is the fuse blown?

--

Go to Step 6

Go to Step 7

6

  1. Turn the ignition ON.
  2. Use a short detector to locate a possible short:
  3. • From the fuse Ef6 to the blower switch
    • From the blower switch to the blower resistor
    • From the blower resistor to the blower motor
  4. Repair any short.
  5. Replace any blown fuse.

Is the repair complete?

--

System OK

--

7

  1. Turn the ignition ON.
  2. Disconnect the power connector from the blower motor.
  3. Use a test lamp to locate a possible short:
  4. • From the terminal 2 of the motor connector to the terminal 3 of the motor switch connector
    • From the terminal 2 of the motor connector to the terminal 4 of the motor switch connector
    • From the terminal 2 of the motor connector to the terminal 5 of the motor switch connector
    • From the terminal 2 of the motor connector to the terminal 6 of the motor switch connector

Does the test lamp light ON?

--

Go to Step 9

Go to Step 8

8

Replace the blower resistor.

Is the repair complete?

--

System OK

Go to Step 10

9

Replace the blower motor switch.

Is the repair complete?

--

System OK

--

10

  1. Inspect the ground of the blower motor.
  2. Repair the ground of the blower motor.

Is the repair complete?

--

System OK

--