This problem is on a 2001 C320 with 36K miles. Multiple other problems such as:

• Turn signals and hazard lights completely inoperative
• Windshield wipers inoperative
• Remote key inoperative except on passenger IR port
• Internal lights inoperative only when doors opened; illuminated okay when key removed from ignition
• Trunk could only be opened manually
• Gas gauge inoperative except low fuel indicator on with full tank

All the above problems were experienced after replacing a failed alternator. Tail & brake lights worked okay at the time. The above problems are all due to the rear SAM (signal acquisition module) failing to initialize properly. MB service confirmed it was the SAM causing the above problems. The SAM replacement service was declined due to inconsistent pricing. Long story...

I was able to get the SAM running again and all of the above problems are now cleared. The current remaining problem is with the tail lights, rear turn signals, license plate, backup and brake lights being completely inoperative. All fuses look fine. I'm finding it hard to believe it is still the SAM since the tail lights were working when the SAM was not. Any hints on what to check would be appreciated.