e car is a 2003 e55

I purchased it in Japan. Very good condition, low km and it shows. BUT I have had it for a month and it has been a month of trying to sort through the bouquet of electrical problems it has thrown me, along with some bad luck/stupidity

When the car arrived it was Jump started, possibly multiple times on the way over the ocean. That I am guessing is problem #1.

Initially it gave me a barrage of codes and messages, which I have cleared off with icarsoft 980, and various reset procedures. 31 of 47 systems had DTCs stored and current.

At this point I have replaced both batteries. Which has solved a few more codes including weirdly enough evap system DTCs.

BUT the following are the problems that persist to one extent or the other and this is becoming extremely frustrating.

1) After the main battery was changed:
a) head unit (Command I guess) will not turn on. Cd changer, display: no signs of life. Fuse 6 (40a) in the Rear Sam was fried. When I replaced it, nothing changed. Is there another fuse for the he command or the display?
b) the only way I can open the trunk is with a physical key, which is a massive PITA. Did I trigger a valet mode? Is it somehow related to the fries fuse? The trunk pop button on the door lights up.

2) yesterday got the dreaded SBC message and breaks went out on me. This also happened before I replaced the batteries and that seemed to have solved it. (Or so I thought)
Code shown C26FB. A7/3n1 SBC internal fault.
Before battery replacement it was accompanied by DTCs for consumer battery shutoff 1 and 2 for undervoltage, a bunch of other messages and preceeded by convenience features disabled message.

3)I measured main battery voltage and overnight it drops pretty significantly.
-When I shut off reads 12.8 or so.
-when I come back the next day could be 12.4 to lowest 11.8! when the car sat longer.
- when running, shows 13.9-14.1 so alternator is charging.
-again all batteries are brand new.

I tried measuring current draw but getting 0 from multimeter. Icarsoft scanner when I check BCM status on shut off locked vehicle even after 5 min shows -2.4A for a brief few seconds then 0. Not sure if this means anything or this is just the draw from the scanner itself. (Seems like a lot)


I cannot help but feel like this is all connected.

Is the rear SAM fried and drawing current?
Battery control module?
Voltage reg? Ive seen it suggested but I don’t think it is.
What could the trunk issue be? Related or separate coincidence.


Any input would be greatly appreciated. I know these are common issues unfortunately on w211s. Makes me really regret getting this car at this point. 😩

I am dreading having to take it to a local dealer as I have had negative experience with them before and I know of no good local indies to entrust this problem to.

Thanks in advance

 

There are many fuses on the left side of the dash as well which can be checked. I'm assuming they're still on the left even if you have a RHD car, or is yours LHD?

 

Fuses and relay list here:
https://mbworld.org/forums/e-class-w...les-chart.html
Be sure to read the whole thread as later posts point out the different wiring harness in the E55 versus the non-AMG W211.

If you do not have Xentry or equivalent aftermarket, you are going to find it very difficult to monitor the electronic modules on the CANBUS. Attachment will give you an idea of the W211 network. Cannot get it to attach. Search for a document titled "219 HO Networking (ACB-ICC) 09-03-02".

For the trunk, pull the side cover inside the trunk (on left side as you are looking into the trunk) and check the electrical harness at the trunk hinge. The harness flexes every time the trunk opens and closes and eventually one or more wires break.

SBC code indicates your SBC unit is bad. You'll need your VIN to find the latest version even though it will be a rebuild.

Network should take as long as 30 minutes to sleep. Quiescent draw should be around 40-50 milliamps. A draw of an amp indicates one of the modules is not going to sleep and is keeping the CANBUS active. A draw of two or so amps indicates a bad module. Quick way to test using a multi-meter is in this thread:

https://mbworld.org/forums/w211-amg/...ain-issue.html

Good luck.

 

Great Post thank you. I have been battling with battery drainage of around 200ma. I think I have isolated it to the alarm system which is on a 7.5 amp fuse in the trunk. After pulling that and letting the car sit for a while my drainage drops to 47ma which sounds like it is inline with your post above being normal draw of 40-50ma. So next will be to remove the alarm in the wheel fender and replace the 7.5a fuse in the trunk hoping that sorts it.

 

Yours is not the first post I've seen about the alarm system causing issues. Now that my car is 15 years old I'm considering replacing the alarm system as preventive maintenance...

 

I should be tackling the alarm system tomorrow. Will report back if that sorts out the high battery drain.

 

I've had the alarm drain issue. As I recall, the car would also turn on fog lights to indicate that problem.
While waiting for a replacement alarm module, I was going to work with a 100' extension cord and battery charger so I could jump it and get home at the end of the day.

 

So said I would report back. Happy to say after disconnecting the alarm siren, my battery drainage is now down to 38ma. Happy days. Should be sorted now.