I have a 2002 e430...recently I was driving and got 2 display messages saying, battery/alternator...I installed a new mb alternator and battery..but the battery is dying cause its still not being charged..and the display message is ofcourse still present..is there some kind ecu reset that has to be done or an alternator fuse that has to be checked..please help...

 

You most likely need a new voltage regulator.
ohlord

 

I had the alternator go when I drove down to Florida one year. I got the same message as you did(2002E320). I just took it to a local shop where he replaced it with a BOSCH one and evething worked fine.

 

oh...i forgot there was another display message that read...battery overcharging..that was on first. then the battery/alternator message came on. so im thinking voltage regulator is bad..does anyone know where the voltage regulator is??

 

This is responding to old post, but adding just in case this is helpful. I have recently experienced the same problem in my 2002 E430. It was a new alternator and I was getting an overvoltage / alternator/battery warning. It also triggered brake assist and abs warning lights. I took alternator out and had it tested by shop I purchased it from. They said it was fine, but when I re-installed, error continued after 10 minutes of driving. My suspicion is that my alternator is not adequate (I paid $160 for aftermarket refurb; I've seen quotes of the Bosch refurb for +$600).

To answer the question above - where is the voltage regulator - it is on (in) the alternator (not the case for much older cars, but most cars these days have alternators that have internal voltage regulators, so I've been told).

I will post what ultimate problem is and the solution