GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Deffoger System Check?

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Go to Step 2

Go to Defogger System Check

2

  1. Disconnect the HVAC control module.
  2. Place the ignition switch in the RUN position.
  3. Connect a test lampJ 35616-200 from CKT 1440 (ORN) at the HVAC control module connector C1 to ground.

Does the test lamp light?

--

Go to Step 4

Go to Step 3

3

Locate and repair an open in CKT 1440 (ORN) between the HVAC control module connector C1 and the underhood fuse-relay center.

Is the repair complete?

--

Go to Defogger System Check

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4

Connect a test lampJ 35616-200 from CKT 141 (BRN) at the HVAC control module connector C1 cavity A to CKT 1050 (BLK) cavity C.

Does the test lamp light?

--

Go to Step 5

Go to Step 6

5

Replace the HVAC control module.

Is the repair complete?

--

Go to Defogger System Check

--

6

Locate and repair an open in CKT 1050 (BLK) between the HVAC control module connector C1 and G200.

Is the repair complete?

--

Go to Defogger System Check

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