Auto Headlamps Will Not Turn Off

SYMPTOM
* AUTO HEADLAMPS WILL NOT TURN OFF

POSSIBLE CAUSES
- No response (BCM) - CCD bus failure
- No response (PCM) - CCD bus failure
- Auto headlamp signal circuit open
- Auto headlamp signal circuit shorted to ground
- Electrochromic mirror defective - sensor stuck ON (default)
- BCM defective - auto headlamp sensor stuck ON