GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Check the R/CMPT REL fuse.

Is the R/CMPT REL fuse open?

--

Go to Step 2

Go to Step 3

2

Repair short to ground in circuit 840 and or circuit 24.

Is the repair complete?

--

Go to Automatic Day-Night Mirrors System Check

--

3

Check the HVAC fuse.

Is the HVAC fuse open?

--

Go to Step 4

Go to Step 5

4

Repair short to ground in circuit 41.

Is the repair complete?

--

Go to Automatic Day-Night Mirrors System Check

--

5

  1. Disconnect the inside rearview mirror harness connector.
  2. Turn the ignition switch on.
  3. Using a test light, probe between the inside rearview mirror harness connector terminal 1 and ground.

Is the test light on?

--

Go to Step 6

Go to Step 10

6

Using a test light, probe between the inside rearview mirror connector terminals 1 and 2.

Is the test light on?

--

Go to Step 7

Go to Step 11

7

Check for a poor connection at the inside rearview mirror connector.

Is there a poor connection at the inside rearview mirror connector?

--

Go to Step 8

Go to Step 9

8

Repair poor connection or open at the inside rearview mirror connector.

Is the repair complete?

--

Go to Automatic Day-Night Mirrors System Check

--

9

Replace the inside rearview mirror. Refer to Inside Rearview Mirror Replacement for service procedure.

Is the repair complete?

--

Go to Automatic Day-Night Mirrors System Check

--

10

Repair poor connection or open in circuit 41.

Is the repair complete?

--

Go to Automatic Day-Night Mirrors System Check

--

11

Repair poor connection or open in circuit 850 between the inside rearview mirror connector terminal 2 and G302.

Is the repair complete?

--

Go to Automatic Day-Night Mirrors System Check

--