hirlemann1

hi, i just bought a 03 silver sl 500 and it had a problem with the generetor, therefore i made it fix , the thing is that the rear battery works perfectly, but the one in the front does not get charge , in consecuence each 2 weeks i have to made it recharge, i took the car to the mb workshop, but they dont have any experience with this car , (is the only one in my country EL SALVADOR) we change the batteries and the problem stills, then they wanted to change the computer and i dont trust thats the right thing to do, i had a volt meter and when the car is with the enginne off, the front battery marks 12.48 volts, when i get the enginne estarted reads 8.30 and once the enginne is running it gets back to 12.48 volts, thats with the front battery, the one in the trunk marks 13.84 with the enginne running and 12.40 with the enginne off. also the abc system is giving me the next problem, when i run the car suddenly Car goes down and the alert comes to the controls with a message ABC PROBLEM VEHICLE TOO LOW, i took it to the mb workshop and the odb computer said that one valve was blocked, but they dont even know where is the central abc pump located in this vehicle, can you please tell where is the abc central pumn located? and also can someone tell me how can i get the electrical wire diagram for this vehicle SL 500 03. I REALLY WILL APPRECIATE FOR ANY HELP
THANKS
HIRLEMANN1

OLDSCHOOLRICE

In regards to the "starter battery" not charging. They are only charged when the battery control module sees fit, but if it is never getting charged it is either likely a bad fuse or the battery control moudle. I would obviously check the fuse first. The fuse is under the subwoofer in front of the passenger footwell on the floor. The subwoofer needs to be removed. It is a large flat fuse, can't remember the amperage but I want to say 150 or 250. When these blow the battery recieves no charge from the battery control module.

As for the abc problem, it sounds like the valve in the valve block that raises/lowers the car is leaking internally causing the car to slowly raise (which you're not noticing). When the vehicle height gets too high the computer notices this and opens the valve that lowers the car. This is the dropping that you're noticing.

The proper repair for this would be a replacement of the valve block that has the issue, and a hydraulic system flush. If the front is raising and dropping it would be the front valve block, if the rear then it would be the rear block.
Front valve block is in front of the left front wheel liner, and the rear valve block is in the fender in front of the left rear wheel liner.

Your ABC pump is located on the left front side of the engine. It is likely worn out. The pump wearing out puts metal into the hydraulic system which gets stuck in the valve seats and causes the leak. You can tell the pump is worn out if it can't maintain pressure around at least 110psi while doing the rodeo actuation.

Good luck with this. Hope this was helpful.

hirlemann1

thanks a lot for answering , i did what you suggest and check the fuse myself, but they were working fine, also replece the rela which is located in the right side of the trunk, (the mb workshop suggested to do it) but didn´t work, then i guess is the battery control module, i don´t really understand how come a car like this can have this kind of problems , its only 7300 miles, however i must to fix it, can you please tell me where is located the battery control module , thanks a lot again for answer me.
HIRLEMANN 1

OLDSCHOOLRICE

Battery control module is under the left side trunk liner. Mounted on the rear of the right fender.

hirlemann1

last question , english as you have already notice is not my mothern language, when you say left side trunk liner, you mean the side of the passenger or the driver? thanks and sorry for that estupid question
HIRLEMANN1

whoover

Assuming you're not in the UK, the driver's side is the left.

OLDSCHOOLRICE

Oops! I meant right side. Sorry!

Dislexia kicking in.

AH1W-COBRA

you can imagine how usefull this forum will be to you.congrats on the MB purchase.i would encourage you to purchase the "STAR SERVICE" service manual library.go to MBusa and see if the dvd is offered in your language,iv'e got to believe it is.this is the same tech manuals that the dealers use to troubleshoot,diagnose,repair your car.it's about a $100 bucks and you wont be able to be without it,given your one of a kind situation.this will give you and your mechanic and better chance of finding problems.im not sure how your gonna overcome the diagnostic scanning issues.MB is a great automobile,hopefully after working a couple of bugs out it will give you years of trouble free operation.

hirlemann1

AH1W-COBRA thank for the tip, i will get te STAR SERVICE manual, and OLDSCHOOLRICE, thanks for your help and regards to your dislexia kicking in ....hope gets better ..lol....WHOOVER, thanks for your answer.thanks to all you guys for your usefull help and for your time ....
HIRLEMANN1

whoover

OSR:

Coincidently, my W220 is in the shop for a valve block and flush. After five years with an S55 and S65 I can spot the signs pretty quickly: steering wheel a bit off center is my clue to check the front fender heights, and sure enought the right was a tad lower than the left.

Anyway, the SA says they're replacing the front right valve block and flushing the system. Does the W220 really have two blocks in the front and the SL one? Or is the SA just in over his head? Or are the blocks somehow combined to save space in the SL?

OLDSCHOOLRICE

S, CL, and SL all have 3 blocks, but only 2 of them are valve blocks that control height. The 3rd one is for measuring system pressure and for absorbing puslations with it's "elephant ball". The front valve block is in front of the left front wheel on all ABC cars. The rear block is a little bit behind where the left rear passenger would sit underneath the car on the S and CL, and in the fender in front of the left rear wheel on the SL.

To whoover, I wouldn't say that your service advisor is in over his head as he can only go off of what he's been told. But the valve blocks have 4 vavles each, for a total of 8 valves. One for raising at each wheel and one for lowering at each wheel. Your dealer is probably replacing the front valve block. This block controls both left and right front raising and lowering. Probably just something lost in translation from technician to service advisor.

whoover

Thanks so much!