• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
---|---|---|---|---|
Mirror Heating Element Supply Voltage | B1640 02 | 1 | B1640 01 | -- |
Low Reference | -- | 1 | 1 | -- |
1. Heated Mirror Malfunction |
The Driver Door Switch (DDS) and Passenger Door Switch (PDS) supply voltage to the outside rearview mirror heater elements upon receipt of a serial data message from the HVAC module indicating that the rear defrost system is active. The door switch supplies B+ through the driver/passenger mirror heating element supply voltage circuit when a request is seen. Ground is applied through the driver/passenger mirror heating low reference circuit.
Outside Rearview Mirror Schematics
Outside Mirror Description and Operation
⇒ | If the rear window defogger indicator does not illuminate, refer to Rear Window Defogger Inoperative . |
⇒ | If the test lamp illuminates, test the supply voltage circuit for a short to voltage. |
⇒ | If less than the specified value, test the supply voltage circuit for a short to ground. If the circuit tests normal, test or replace the applicable rearview mirror face. |
⇒ | If not within the specified range, test the supply voltage circuit and the low reference circuit for an open/high resistance. If the circuits test normal, test or replace the appropriate rearview mirror face. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for DDS or PDS replacement, setup and programming |
• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category |
The R/DEFOG relay supplies voltage to the outside rearview mirror heater elements based on the current state of the rear window defogger. The replay supplies B+ through the driver/passenger mirror heating element supply voltage circuit when a request is seen.
Outside Rearview Mirror Schematics
Outside Mirror Description and Operation
⇒ | If the rear window defogger does not turn on, refer to Rear Window Defogger Inoperative . |
⇒ | If greater than the specified range, test the ground circuit for an open/high resistance. |
⇒ | If the test lamp is always ON, test the B+ circuit for a short to voltage. |
⇒ | If the test lamp is always OFF, test the B+ circuit for a short to ground or an open/high resistance. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.