Nomondays ForMe

Had to use the physical key to unlock the car door.
No dash lights, no dome light, no headlamp or tail lights, no horn, no accessories, nothing that's battery powered will function.
The battery under the hood is Functional, terminals are not corroded, and it's FULLY charged showing 12.7 volts.
Unable to unlock the trunk electrically and the manual key won't unlock it either.
Is there a "Master" Fuse or Circuit Breaker that can cause this symptom?
If so, please describe where it's located.
If not can somebody please tell me what to check, where to look for the cause.
> > UPDATE > > I had posted this onto the R231 Forum yesterday (06/26/2019) and was asked to post onto this R230 forum.
ADDITIONALLY > I've had the SL550 transported to the Mercedes Dealership for them to troubleshoot and repair.
When the car has been repaired I'll post the results/remedy to this forum.

alk247

Did you check your "consumer" battery in the trunk? Did the car start?

Eric79

I'm thinking the consumer battery also.

Nomondays ForMe

Car would not start.
Nothing electric would work.
Was unable to open the trunk as nothing electric would work AND using the physical key would not release the trunk - It Was STUCK CLOSED!!!

Nomondays ForMe

Thanks for your reply.
The Mercedes Dealer Service Department now has the car and I'll report their findings as soon as the problem has been remedied.
Yes, I agree the Consumable Battery is a likely culprit.

alanb813

I have the same model (2007 sl550) and the same problem. What did the dealer find and the fix?

Nomondays ForMe

Had the car flat-bedded to the dealer late in the day. (BTW > > The tow truck driver couldn't start the car either.)
The following morning the dealer service folks phoned to say the car 'started right up' . . . . no problem found!!!!
Yes! I know! It's a mystery!