For 1990-2009 cars

## Automatic Day-Night Mirrors Inoperative LWB

### Diagnostic Aids

Important: The automatic day-night feature of the inside rearview mirror may not operate properly or become inoperative due to an intermittent short to battery positive voltage in the backup lighting system.

Step | Action | Values | Yes | No
--- | --- | --- | --- | ---
Schematic Reference: Inside Rearview Mirror Schematics . Connector End View Reference: Component Connector End Views
1 | Did you review the operation of the automatic day-night feature of the inside rearview mirror and perform the necessary inspections? | -- | Go to Step 2 | Go to Symptoms - Stationary Windows .
2 |

1. Turn the ignition ON, with the engine OFF.
2. Turn ON the automatic day-night feature of the inside rearview mirror.
3. Cover the sensor on the inside rearview mirror back, facing the windshield.
4. Shine a bright light into the sensor on the inside rearview mirror face, facing the rear window.

Does the inside rearview mirror darken?

--

Go to Diagnostic Aids

Go to Step 3

3 |

1. Turn the ignition OFF.
2. Disconnect the harness connector of the inside rearview mirror.
3. Measure the resistance between the ground circuit of the inside rearview mirror and a good ground.

Is the resistance less than the specified value?

xx

Go to Step 4

Go to Step 9

4 |

1. Turn the ignition ON, with the engine OFF.
2. Measure the voltage between the accessory voltage circuit of the inside rearview mirror and the ground circuit of the inside rearview mirror.

Is the voltage within the specified range?

xx

Go to Step 5

Go to Step 10

5 |

1. Place the transmission in PARK.
2. Measure the voltage between the backup lamp supply voltage circuit of the inside rearview mirror and the ground circuit of the inside rearview mirror.

Is the voltage less than the specified value?

xx

Go to Step 6

Go to Backup Lamps Always On .

6 |

1. Place the transmission in REVERSE.
2. Measure the voltage between the backup lamp supply voltage circuit of the inside rearview mirror and the ground circuit of the inside rearview mirror.

Is the voltage within the specified range?

xx

Go to Step 8

Go to Step 7

7 | Test the backup lamp supply voltage circuit of the inside rearview mirror for an open or high resistance. Refer to Circuit Testing and Wiring Repairs . Did you find and correct the condition? | -- | Go to Step 12 | Go to Backup Lamps Inoperative .
8 | Inspect for poor connections at the harness connector of the inside rearview mirror. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs . Did you find and correct the condition? | -- | Go to Step 12 | Go to Step 11
9 | Repair an open or high resistance in the ground circuit of the inside rearview mirror. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 12 | --
10 | Repair an open or short to ground in the accessory voltage circuit of the inside rearview mirror. Refer to Wiring Repairs . Did you complete the repair? | -- | Go to Step 12 | --
11 | 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 12 | --
12 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2