GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Did you perform the Automatic Day/Night Mirror System Check?

--

Go to Step 2

Go to Automatic Day-Night Mirrors System Check

2

  1. Turn the ignition switch to the ON position.
  2. Put the transmission in the REVERSE position.
  3. Inspect the backup lamps.

Are the backup lamps ON?

--

Go to Step 3

Go to Backup Lamps Inoperative

3

  1. Disconnect the inside rear view mirror connector.
  2. With the transmission in the REVERSE position, use the DMM to measure the voltage between terminal 10 of the inside rear view mirror connector and a known good ground.

Is the measured voltage within the specified value?

B+

Go to Step 5

Go to Step 4

4

  1. Locate an open or a high resistance in circuit MF900.
  2. Repair the open or the high resistance in circuit MF900.

Is the repair complete?

--

Go to Step 6

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5

Replace the inside rear view mirror. Refer to Inside Rearview Mirror Replacement .

Is the replacement complete?

--

Go to Step 6

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6

  1. Connect all connectors and components that were disconnected.
  2. Verify that the automatic day/night mirror operates properly.

Does the automatic day/night mirror operate properly?

--

System OK

Go to Step 1