Causes for ASR and ABS light to come on

[demetrios]

Hi all
So I've had my R129 500 SL for 5 yrs. Every so often the ASR and ABS lights come on. Normally car is over revving by 500rpm ish and after a couple minutes it stops and back to normal.
Yesterday while driving The transmission gets really violent and clunky. Park to reverse jolts the car and its over revving to 2000rpm. Engine temp is rising slowly and without foot on break the car is accelerating slowly on it's own.

I've read that it could be the VFC needs changing and to do water pump too. I'm gonna check the fan shortly to see if its spinning freely as says should need some force to spin a few times otherwise if it spins easily its knackered.

Are these easy to change or shall I let mechanics at it?
Also should water pump be changed?

Any other causes for ASR to come on?

 

[demetrios]

Nobody knows then?

 

[rf065]

Have you had it on STAR and read the codes yet?

 

[grober]

IIRC your car is a 92 model? All your problems point towards low voltage- which will cause the abs/asr to lightup because the system has a minimum voltage threshold below which it will register a fault/inoperative. Your car has also sat unused for consideable periods of time meaning many contacts may have developed thin layers of corrosion due to galvanic action between dissimilar metals- this particulary applies to the ceramic fuses in the main fuse box whose contacts should all be cleaned. Problems there can give a bewidering range of symptoms all over the car. Other things to check would be the alternator [ brushes /output] and main engine earth strap. You need to get the car to a MB specialist familiar with this age of model- they will know what to look for.

 

[demetrios]

IIRC your car is a 92 model? All your problems point towards low voltage- which will cause the abs/asr to lightup because the system has a minimum voltage threshold below which it will register a fault/inoperative. Your car has also sat unused for consideable periods of time meaning many contacts may have developed thin layers of corrosion due to galvanic action between dissimilar metals- this particulary applies to the ceramic fuses in the main fuse box whose contacts should all be cleaned. Problems there can give a bewidering range of symptoms all over the car. Other things to check would be the alternator [ brushes /output] and main engine earth strap. You need to get the car to a MB specialist familiar with this age of model- they will know what to look for.

Thank you for the reply. Yes it's a 92 model. I was hoping for a simple thing which I could do before taking it to MB specialist because I worry of cost lol. It's worth it as it's only car I've ever had that appreciates in value and ive never spared any expenses on it so far.

 

[grober]

Its quite possible that all these symptoms you are experiencing are down to one easily rectified faulty component or connection dragging the entire electrical system voltage down. Problem is it may be intermittent which makes it difficult [ time consuming] to track down That's where an experienced pro comes in they know where the usual suspects are! Unfortunately your car is really pre canbus which generates fault codes on later models. In terms of cars lying inactive over winter causing electrical problems the maxim is avoid warm and wet [ garage] much better is cold and dry [carport]

 

[demetrios]

Have you had it on STAR and read the codes yet?

Hi
No I havent. Is that at a mercedes specialist?

 

[Smart320]

Yes you need either a dealer or a Mercedes Specialist who has access to the Star diagnosis system, not a generic code reader

 

[ray_hennig]

In the early days of my 300CE (around 1998), I had this issue of ABS and ASR lights coming on. It was accompanied by a throbbing sound (not ABS engaging) from the ABS/ASR pump. When the throbbing stopped, on came the lights.

The MB garage that sold me the car investigated and were baffled so they bled the brake system repeatedly and that, apparently, was the solution. No ABS/ARS lights since.

Incidentally, I do hear that throbbing noise, momentarily, if I lose traction at the rear; it must be something to do with ASR engaging. Maybe someone who knows better that I can comment?

Best to all.

RayH

 

[Deletedmember130310]

I worry of cost .....

.... ive never spared any expenses on it so far.

????

 

[demetrios]

????

Lol sorry yes that's a slight contradiction

So far since I've purchased it, ive only ever replaced a radiator which was over £500 inc fitting, an alternator and 2 batterys.
Also had new front wing as was rusting around wheel arch on drivers side and just re-spray to rear bumpers.

I'm worried that this fault will cost me thousands but I dont know about these things to form an educated guess. Engine is lovely and smooth and it's only this that is an issue

 

[ivan1983]

Was this confirmed as 1992 car, if its later could be wiring loom issues.
Could also be brake switch if the light comes on after touching the brake pedal?
As suggested it really needs to go on a star.

Depending on how good you are with a soldering iron you could make a reader http://www.mercedes.gen.in/mercedes...FjAAegQIARAB&usg=AOvVaw2nOZxDbon1MUkMYsmf_7oQ