GM Service Manual Online
For 1990-2009 cars only

Step

Action

Yes

No

Schematic Reference: Automatic Day-Night Mirrors Schematics

1

Did you review the Automatic Day-Night Mirror system operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Stationary Windows

2

  1. Turn ON the ignition, with the engine OFF.
  2. Turn ON the temperature display on the inside rearview mirror.

Does the temperature display show a temperature reading?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 3

3

  1. Turn OFF the ignition.
  2. Disconnect the ambient air temperature sensor.
  3. Connect a 3 amp fused jumper wire between the signal circuit of the ambient air temperature sensor and a good ground.
  4. Turn ON the ignition, with the engine OFF.

Does the temperature display show SC?

Go to Step 4

Go to Step 5

4

  1. Turn OFF the ignition.
  2. Connect a 3 amp fused jumper wire between the signal circuit of the ambient air temperature sensor and the low reference circuit of the ambient air temperature sensor.
  3. Turn ON the ignition, with the engine OFF.

Does the mirror temperature display show SC?

Go to Step 7

Go to Step 6

5

Test the signal circuit of the ambient air temperature sensor for an open or short to battery positive voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 8

6

Test the low reference circuit of the ambient air temperature sensor for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 8

7

Inspect for a poor connection at the harness connector of the ambient air temperature sensor. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 9

8

Inspect for a poor connection at the harness connector of the inside rearview mirror. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 10

9

Replace the ambient air temperature sensor. Refer to Ambient Air Temperature Sensor Replacement .

Did you complete the replacement?

Go to Step 11

--

10

Important: Perform the Compass Calibration and Variance procedure for the inside rearview mirror with compass.

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

Did you complete the replacement?

Go to Step 11

--

11

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3