Error message undervoltage consumer defective

[arasmith1]

Light came on this am on my 2002 C320 "undervoltage consumer defective". After shutting down, light did not come on. Original battery still in car. thoughts???

[Bellardia]

How's your 2002 C320 now?

The same thing happened to my 2002 C320 on May 16. The car's been fantastic, and then out-of-the-blue the undervoltage consumer defective (orange) comes on the dash. [Interesting how two separate vehicles would get the same message around the same time.]

Its original battery passed the loadtest. Of course, experts have advised that such batteries call for a replacement (life of a battery is 3 - 5 years).

The MB dealership probably will advise getting a new battery. Then if you still get the undervoltage consumer defective on the dash, then they'll probably recommend replacing the alternator.

If you come across anything else, please do share.

[JoesC320]

Hello,

Well my 2002 C320 posed that same error message this morning while driving to work. I was very confused. The message was gone when I went out for lunch. I would appreciate any info. And, BTW, I also have the same seat control module problem as all the others. I have replace both seat modules and still have problems with battery drain from time to time.
Thanks,

Joe

[Bellardia]

Apparently with my 2002 C320, I allowed the MB dealership to replace the original battery and alternator since I last posted. Yet within a couple of days, I've noticed that my car is worse than before.

Unlike it's old very responsive and zippy self, this car now hesistates after stopping at a stop sign or stop light; it gives me a gentle side-to-side shake before regaining any speed. On the freeway or even during consistent driving at lower speeds, it feels as though it has lost power.

Personally, I'm not liking this one bit.

[French75]

This obscure error message began appearing in our 2001 C240 a few months ago. The vehicle is usually parked all week and then drives a 250 round trip on the highway to our vacation home. We had the battery checked and it was OK. We kept driving it, and as usual, the message appeared from time to time - came on and then was clicked off OK. No problems driving. One day we took the car out for stop and go driving in the city and the battery went dead, leaving it stuck in a parking garage. We summoned a local Mercedes mechanic who read the voltage from the alternator at 11v, when it should be around 14. After replacing the alternator/voltage regulator the car works fine and the message no longer appears.

[eric242340]

Originally Posted by Bellardia

Apparently with my 2002 C320, I allowed the MB dealership to replace the original battery and alternator since I last posted. Yet within a couple of days, I've noticed that my car is worse than before.

Unlike it's old very responsive and zippy self, this car now hesistates after stopping at a stop sign or stop light; it gives me a gentle side-to-side shake before regaining any speed. On the freeway or even during consistent driving at lower speeds, it feels as though it has lost power.

Personally, I'm not liking this one bit.

It needs a relearn proceedure kick it's ass both expressway and roadwork for a few kkks and it will relearn. You will be supprised at the difference.