SL 500 battery light

[sam leason]

Hi,I have just brought a SL 500 2008 witch i love. It has just got the red battery light coming on the dash panel.I checked the rear battery with a volt meter.It showed 10.8 volts then started the car and repeated the test and got 13.6 volts.So i changed the battery. The light is still on.
The car was them sent into a Mercedes service garage.After two days they told me it was the battery management box? at a cost of £1300.00 fitted and did not get rid of the battery light.Then i was told it was another part witch was then sent out from Germany.Comes in two parts!!! only one arrived.
I have told the garage to put all my old parts back on and we will put it down to experience.
Is there a Mercedes update on the electrics ?? or what might be up with my car.

 

[mioba]

welcome to the forum. Where are you located. Seems you need a better garage as a start. Maybe someone can point you in the right direction.

 

[Wighty]

As above , you need an MB specialist buddy

 

[mioba]

out of curiosity i searched MB battery unit. Most expensive i found was 150 notes. If you google the pn of the control box you got, it would be interesting to see the price to justify 1300.

 

[alexanderfoti]

Yes, wonder what they are referring to. BMS sometimes fails, but not too expensive, sits on the negative lead. Get it to a good local indy, should sort it straight off.

 

[sausage]

Optimistic approach: The car has been in the trade and possibly not used. During my first week of ownership (maybe longer) I saw the battery warning message light up a couple of time. I took it for a long drive and I have not had the warning since (10k miles/9 months).

 

[NJS5]

Welcome Sam

As already asked - where are you located?

NJSS

 

[sam leason]

Wolverhampton

 

[sam leason]

Well I have told them to put all my parts back on and will pick up tomorrow. Watch this space.

 

[bluesl]

Then what happened??

 

[star]

Battery control modules are very expensive on the SL’s and have recently gone up. They are different to 211 e classes and can catch fire. We have a car in from another specialist in which they replaced the bcm and the light was still on. We replaced the control relay and then had to dig deeper. Problem now solved.

 

[bluesl]

I have the feeling that the R230 is proving a significant liability as it gets older. My experience is that it is very robust mechanically but what surrounds the core drivetrain - brakes, suspension, electronics, hydraulics - is a total nightmare. No wonder residual values are so poor.

 

[star]

I have the feeling that the R230 is proving a significant liability as it gets older. My experience is that it is very robust mechanically but what surrounds the core drivetrain - brakes, suspension, electronics, hydraulics - is a total nightmare. No wonder residual values are so poor.

Isn’t that the problem with all cars?? The newer the car, the worse it is.

 

[bluesl]

I think the R230 is a particular problem. Complexity was piled in without regard to the maintainability. I’ve owned my SL55 from new in 2002. The level of failures and recalls has been shocking. It’s no coincidence that the much vaunted SBC brake by wire system was dumped in future models. The SL, the E-Class, the Maybach and the McLaren-Mercedes were the only models to get it.