jagharvest

Hi
I have an sl500 230 2003 model.
Since buying the car in middle january there has been an ongoing problem with the battery?
The usual warning comes on stating consumer electrics off line, also braking efficiency reduced start engine or even take to workshop?
Had it checked over at a local mb specialist and he changed the battery for a new mercedes gel battery but 2 weeks down the line of using the car on a regular basis (most days and motorway driving on the wk ends!!!) i am getting the electrics off line again, the doors opening with the key only!!
PLEASE HELP !!
Regards
Tony
PS The parking assist has stopped working this morning also, even when the rest of the electrics come back on line???

diablo2112

This is just an educated guess. Your R230 triggers those warnings when battery voltage is low (and don't forget, you have 2 batteries in the car - one for accessories, one for the engine). If you replaced both batteries and are still getting warnings, then the charging system is suspect. Either the alternator or the serpentine belt. Did you check alternator output with your mechanic?

B-tsai

Sounds like the voltage regulator.

https://mbworld.org/forums/w211-amg/...lternator.html

Make sure you get the right part number, the post above was for the E series, SL is slightly different part number.

seven_out

This statement suggests to me that the charging system is probably okay. I read the original post and formed the impression that the batteries are charging properly, and when the car sits for a while the Consumer Battery is becoming discharged. Maybe I have misunderstood the symptoms of the problem...

jagharvest

Hi
Just to add to my original post...
Never have a problem with the starter motor battery in the front, always plenty of juice in that one.
It's the consumer battery in the boot being discharged over night when not being used, that's my problem???
Cheers
Tony

diablo2112

It's possible there's some circuit drawing current off the accessories battery. A great way to check for this is to turn the car off, disconnect the negative terminal on the trunk battery, and then connect a multimeter (with amps readout) between the negative terminal and the disconnected cable. The idea is to complete the circuit through the multimeter. Most multimeters have 2 connections, one for low current, one for high current. I usually connect through the high-current terminals first. You can then read (in amps/milliamps) any current being drawn from the battery.

If you do find a current draw (of greater than a half amp or so), you can then selectively remove fuses from the fuse box to see what circuit is causing the problem. This usually gets you close enough to identify the culprit.

Good luck.

seven_out

If you only get the "offline" message when the car has sat for a while, then yes, I suppose the Consumer Battery discharging is your problem.

I would suggest checking the quiescent current drain on the battery as diablo suggested. Have the trunk closed, or simulate a closed trunk by closing the catch on the trunk latch. According to M-B you should lock the car and wait 20 minutes before reading the measured current. You should read 50mA or less. If you don't, then you need to investigate further.

jagharvest

Thanks guys for the feedback and advice.
Cars in local specialist now, there is a drain and they are trying to find the source at the moment. Hopefully ready tomorrow?
Thanks again.
Tony

diablo2112

You're welcome. Do report back what they find, always good to document these things for other owners.

seven_out

Steve Brotherton is a mechanical engineer, Mercedes tech, and owner of a repair shop in Gainesville, Florida. When faced with a battery drain problem he suggests that the first thing to check is the state of the interior CAN bus (CAN B). He explains all here.

To quickly identify a circuit causing battery drain Mercedes recommends leaving the fuses in place instead of removing them. The circuit with the high current draw is determined by measuring voltage drops across the fuses and looking for an unusually high value. Since an '03 car has no fewer than three fuse boxes, this shortcut can save an owner paying expensive shop labor.

Philip317

I have the same problem with my R230. New batteries ( x 2) haven't made any difference. What a mess these cars are. Everywhere you look on this web site we see nothing but electrical problems. Shouldn't ave such problems with such expensive cars

seven_out

Perhaps you are correct, but I don't perceive matters to be nearly that bad. At any rate, on a positive note having access to a Mercedes' SDS makes many/most of these problems damn quick and easy to troubleshoot, and that may include whatever issue(s) you are experiencing.

Philip317

Hi Diablo

I have the identical same problems with mine and even when I replaced both batteries the problem is still there.

I'm nor overly worried as it doesn't affect the performance of the car but what I'm concerned with is the transmission problems which can occur anytime and presents itself it total loss of powere and that's the one to worry about. Hope you don't experience that problem as that is the scary one. It's incredible that MB knowing that they have these problems out there do not tackle them as it s going to influence people ad to what they will buy next - for me it certainly will not be an MB!
Take care
Philip

jagharvest

Hi
Well after owning this beautiful looking beast for 3 months I have had the oportunity to say goodbye (Thank god !!!)
The car sales where i bought it say enough is enough and offered to take the car back for what i payed for it, so I jumped at it !( 3 months warranty)
The sl500 r230 that I owned(with full service history !!) was seriously flawed with a mass of problems mostly down to the stupid design of the braking and suspension systems.
The electric problems that I mentioned at the start of this thread were finally diagnosed as a problem with water ingress beneath the drivers well where an old switch had shorted out giving a battery drain of 0.64amp??
they got this down to 0.05 after many hours of investigation.
So after spending a six figure some on this problem and many other faults the list is something like this :-

two new batteries
hydrolic susspension drained flushed and new oil (it was accrid black)
new rear boot struts
cd auto changer not working / replaced
sat nav not working/ not repaired!
trickle charger purchased / not used
two new rear tyres
air con not working/ not repaired
front underneath engine cover kept falling off after 50mph / fixed by myself with better more heavy duty screws and plastic ties
roof elevation when in boot not working/ repaired
Parking assist not working / module replaced



Approx spent by myself 1000

Car sales spent 2000


The warning / malfunction messages coming up are still "start engine reduced braking and inefficient braking system start engine and visit workshop"
Diagnostic at very good auto electricians is the sbc pump knackered! 1200 pounds just to purchase plus labour.

The front off side suspension leg is leaking oil so that will fail next mot and a massive bill there too !

SO after 3 months and 2k spent with at least another 3k to go this beautiful car has gone and I now have a vw polo 1.6 tdi (almost brand new for the same money and no stress when jumping into it and taking it for a spin!)
I shall be looking for something "special" again next year, what a shame the r230 is such a "lemon" but there you go my own fault for not visiting this site before purchase !!!
Thanks for all your help.

Cheers

Tony

seven_out

Perhaps now you should harvest a Jag F-Type roadster with the V-6 supercharged motor?

Philip317

Nice pun Rod!!!

Well done Tony - you made the right decision. These cars are crap. Hope that more people like you make the same decision. MB must be told that people will not stand for this excuse of a car. Why can't they deal with customers like Lexus does and treat their customers properly.