Component Tests and General Diagnostics

1. Make sure Engine is RUNNING when trying to activate Rear Defogger and Heated Mirrors.
2. Check for open RR DEFOG Fuse or A/C Clutch Fuse.
3. If Rear Defogger works, but Heated Mirrors do not, check for open HTD MIR Fuse.
4. If some of the grid lines do not heat, refer to Body Electrical section for diagnosis.
5. If Central Control Module (CCM) Code 22 is set, refer to Body Electrical section for diagnosis.
6. A rare condition may occur with the Electronic A/C System only. The Central Control Module (CCM) may not recognize the Rear Defogger "ON/OFF" Switch on the first attempt. Try several times before determining if there is actually a problem.

^ Check for a broken (or partially broken) wire inside of the insulation which could cause system failure but prove "GOOD" in a continuity/voltage check.
^ Check for proper installation of aftermarket electronic equipment which may affect the integrity of other systems.