GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Has the Defogger System Check been performed?

--

Go to Step 2

Go to Defogger System Check

2

  1. Disconnect the HVAC control module connector C1.
  2. Connect a J 35616-200 test lamp from cavity C of connector C1 to B+.

Does the test lamp light?

--

Go to Step 4

Go to Step 3

3

Locate and repair open in CKT 150 (BLK) between HVAC control module connector C1and G200. Refer to Wiring Repairs in wiring.

Is the repair complete?

--

Go to Defogger System Check

--

4

  1. Disconnect the HVAC control module connector C3.
  2. Connect a J 35616-200 test lamp from cavity 2 of the HVAC control module connector C3 to B+.

Does the test lamp light?

--

Go to Step 6

Go to Step 5

5

Locate and repair open in CKT 150 (BLK) between HVAC control module connector C3 and G200. Refer to Wiring Repairs in wiring.

Is the repair complete?

--

Go to Defogger System Check

--

6

Connect a J 35616-200 test lamp from cavity B of HVAC control module connector C1 and ground.

Does the test lamp light?

Go to Step 8

Go to Step 7

7

Locate and repair open in CKT 141 (BRN) between the IP fuse block and the HVAC control module connector C1. Refer to Wiring Repairs in wiring.

Is the repair complete?

--

Go to Defogger System Check

--

8

Replace the HVAC control module.

Refer to Control Assembly Replacement in instrument cluster.

Is the repair complete?

--

Go to Defogger System Check

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