'96 E320 electrical glitch
 

I have a '96 E320 (55,000 miles) driven by my wife that occasionally exhibits electrical abnormalities. The most disturbing is a complete loss of all electrical power to accessories. For instance, one day she was pulling out of garage at work, and everything stopped -- lights out, wipers stopped, installed phone disconnected -- just for a second and then resumed. Also, since new, it occasionally shows ASR and Defective Lamp messages even though all appears to be working. It seems worse when the weather is wet. I haven't let the dealer take a crack at it yet, because on my first call he said it's probably a battery or alternator, which seemed to me to be a very naive assessment of possible causes! The battery is replacement MB OEM 18 months old. It has had a lighting wiring harness update provided by MB. I would very much appreciate your thoughts! Thank you.
John Doyle

It sounds like the ignition switch. We have replaced several!