Igor911

Driving in stop-and-go traffic the other day, and all of a sudden strange messages began to appear on my dash. "48V Battery" and "Malfunction". As soon as the errors appeared, the car seemed to bog down, and would not go past 30 MPH (even if you floor it). Seemed scary at the time considering I was on the highway...

In any case, I managed to get into the emergency lane and power cycled the car. Once restarted, I noticed the check engine light was on but the car appeared to be functioning as expected. I immediately drove it straight to the dealer on my way home and left it to be diagnosed.

1,700 miles on the clock... Anyone else having similar symptoms?

petee1997

Not yet.

Rick2019

Not happy to hear that.
Just curious- CLS 450 or CLS 53 AMG?

I would’ve called MB roadside immediately. That car was too dangerous to drive another mile.

Keep us informed.

Mihir Ashar

I was driving on the highway as well, when my ac started blowing hot air suddenly after about 20min of driving. I pulled the car to the side of the road and restarted the engine, and the ac was working fine.
After about 4 hours again the ac was blowing hot air, and this time I got an error message on my dashboard saying "The 48V battery is malfunctioning"; so I pulled over again and restarted the engine, was working fine again.

I called MB support and they said to bring in the car after 3 days (In the UAE, public/private sectors closed for Eid)

Strange thing is, I just took delivery of my car literally 2 weeks ago, only 500kms on the car!
Waiting to take it to the service centre and get it checked ASAP!

Any update on yours after you got it checked?

Igor911

yes, the dealer told me they had to perform a few software updates to the cars computer. I've put on about 3000 miles since the incident, and have never seen the issue rear its ugly head again. Problem solved

hendy.yurinata

Same Here with C200 EQ48V w205..

Anyone had info on ECU updates from Benz? Mine only had like 4.6k miles on it.. I dont think replacing the 48V would fix this as it may reappear again

hendy.yurinata

have the problem occured again ever since?

places

48V are problems. There is a current and long thread on the GLE sub on this very topic.

Igor911

as a quick update, I have not had this problem occur again after the dealer performed the updates.

konigstiger

MBUSA released Service Campaign 2020110017 software for the on-board electrical system battery control unit does not correspond to the current series production configuration, dealer will update.

Shiv Umapathi

Thanks for this, I will know what to do, if an when i have this problem on my 2020 CLS 450 4MATIC.