The inside rearview mirror uses 2 magnetic field sensors for compass direction. One sensor is for the north and south, the other sensor is for the east and west. The mirror supplies a signal and low reference to each sensor. As the vehicle travels with or against the earth's magnetic pull, there will be a change in voltage on one or both sensors. As a result of the change in voltage, the mirror changes the heading on the compass display.

Schematic Reference

Connector End View Reference

Electrical Information Reference

Scan Tool Reference

Scan Tool Data List

1. Ignition ON, verify that the mirror compass does not display "C" or "CAL".

⇒	If the mirror compass displays "C" or "CAL", perform the Compass Calibration and Magnetic Variance procedure. Refer to Compass Calibration and Magnetic Variance .

2. Verify that the mirror compass display is not blank.

⇒	If the compass display is blank, replace the inside rearview mirror.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.