GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

1

Verify the customer complaint.

Are the customer concerns verified?

Go to Step 2

System OK

2

Move controls other that the temperature adjustment.

Is an excessive effort required to move the controls?

Go to Step 15

Go to Step 3

3

Move the temperature control.

Is an excessive effort required to move the controls?

Go to Step 6

Go to Step 4

4

Move the temperature control.

Does the temperature door move too easily?

Go to Step 5

System OK

5

Remove the cable from the controller.

Does the knob turn freely, without the click stops?

Go to Step 15

--

6

Check the cables for improper routing, kinks, wiring interference, or other instrument panel interference.

Is there a problem?

Go to Step 7

Go to Step 8

7

Repair as needed.

Is the repair complete?

System OK

--

8

  1. Remove the cable from the temperature door.
  2. Cycle the door manually.
  3. Check for door binding.

Is there any door binding?

Go to Step 9

Go to Step 12

9

Check a binding door for shaft alignment, a bent shaft, or a warped case.

Is the door seal OK?

Go to Step 10

Go to Step 11

10

  1. Check a binding door for a shaft alignment, a bent shaft, a bent door, or a warped case.
  2. Repair as needed.

Is the repair complete?

System OK

--

11

Repair the door seal, as needed.

Is the repair complaint?

System OK

--

12

Check for control binding.

Does the control bind?

Go to Step 14

Go to Step 13

13

  1. Reinstall the cable to the door.
  2. Check the clearance for the cable-to-dash components.
  3. Repair any interference.

Is the repair complete?

System OK

--

14

  1. Remove the cable from the control.
  2. Check the control for binding.

Does the control bind?

Go to Step 15

Go to Step 16

15

Replace the control.

Is the repair complete?

System OK

--

16

Replace the cable.

Is the repair complete?

System OK

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