Interesting M104 Code problem-fix
 

I had an occasional code (can't remember the number) that was some kind of communication error code on my '94 E 320. Car is seldom used in winter, started only when the roads are dry, battery isn't charged when not used.

My serp-belt has been squealing on startup all winter, but generally in good condition, tensioner had gotten weak.

Replacing the tensioner and belt has caused the code to no longer pop up, so here's what I'm thinking:

Long time parked, started, battery marginal/low. Load on the belt including the alternator, probably low voltage, and usually lights and blower and seat heaters right away to add to the problem.

New belt and tensioner likely allowing the alternator to output properly at startup, getting good voltage to the computers now is my guess.

Just a thought in case anyone else is having similar symptoms.

sounds like perfect automotive logic to me.keep it up we don't have enough competent thinkers in this world.