Just finished all the jobs to make the car perfect and another problem comes up!The abs light comes on nearly all the time after the car has been used for 2-3 miles.Having done a sarch could it the over voltage relay relay fuse,if it was surely the light would stay on all the time?I have recently jump started the car after doing the head gasket but it runs like a dream so does the relay theory hold any water?Is it more likely to be a sensor gone down or do the wires corrode?
Thank you in anticipation of your help.
Hamish
ps 90 w124 wagon

Replace the ABS fuse, even if it isn't bad. It's worth a try and possibly the cheapest solution.

Thanks for the speedy reply!when you say abs fuse do you mean the one in the main fuse box or do mercedes hide them elsewhere!
Again thanks

You know, funny question, because I was hoping you'd know!
I am not sure, you should look first in the main fuse box in the engine compartment first. I can't recall where mine is. Then try the other fuse boxes. Many times the ends of the fuses can get corroded and provide a poor connection.
Good luck with finding the fuse! ...shouldn't be too hard.

GOOD answer I like your style!Would you agree that it is probably not the relay?

Yes, I have never heard of the ABS relay failing, not even sure if there is one. Good luck and let us know if your problem gets solved. There could be other solutions too, but the techs will probably be more appropriate assistants for that! CYA later.

Hamish, when my ABS light came on, it was intermitent. Turned out to be the overvoltage relay. So if the ABS fuse does not fix the problem, I would suggest the overvoltage relay as the next thing to check.

300SL-1993

Thanks for your reply. Did you have to replace the whole overvoltage relay or just the fuse on top? If it was the whole relay, what is the ballpark figure for cost? Hamish

It is about $50.00 ... not bad at all.
You can get it here at Partsshop. It's the cheapest of anywhere else. I searched all over and this is the cheapest place for most parts.

Hamish, ...another possible cause on this problem could be that, ...your ABS sensors are either dirty or defective. These are normally located on your front wheels, ..check it out. Remove and clean it as required, ..then perform resistance test. Let me know what you found out.

I would vouch for the sensors as they're extremely sensitive.

Failing which, run your MB down to the workshop and get the ABS tested to be on the safe side.

Got up early !There is no fuse for the abs system in the main fuse box!So it must be the sensors or the relay(ov).The ov relay did not make itself odvious behind the battery but I shall do a search !There are two relays but neither seem to have any sign of afuse on them ,is it the one on the end of the abs ecu or is it the one behind?
thank you for the replies.
does the parts shop ship to the UK!
Hamish

I asked the same question on whether the parts shop ship to Malaysia (keen on supporting the shop), but I had no response.

I don't know if it remains competitive if shipped to UK.

Hamish:

The OVP is a small relay buried down next to the 2 visible relays. You should see a finned aluminum box with a major cable that runs parallel to the firewall. Closer to the firewall are the 2 relays you probably see - one of them closest to the firewall should say "klima" on top. right next to that and towards the center of the car, and buried a little lower than the other 2 relays is the OVP relay. If you assume the top of this page is the firewall and the bottom of the page is the battery, the right edge of the page is the engine and the left edge of the page is the fender, then the whole arrangement looks like this _:' where the _ is the computer, the : are the 2 relays, and the ' is the OVP relay.

abs light coming on!
 

I had an intermittant ABS light coming on in my 88 300E and it turned out to be a bad battery. When the voltage drops below a certain point (10 volts I think) the ABS system is disabled as it could become un-reliable. try checking your battery voltage and charging system. Mine was a shorted cell and replacing the battery fixed the problem.

Many thanks to you all for your replies!I have been to see the dealer who is good with advice ,he seems to think it will be a sensor problem, just clean not replace.I hope he is right as a new sensor is £100!!!The over voltage relay is only £40 so if the problem persists it maybe worth a try now I know where it is!The light did not come on today whilst I was driving but it came on whilst my wife was so it maybe just her imagination(wishful thinking!).The OVR definetly has a replaceable fuse,yes?
Again thanks.
Hamish

Where exactly are the wheel sensors? I have been getting the ABS light also.

Also had the ABS light come on on the 560SL. It was one of the front wheel wires going from the inner wheel well to the sensor at the rotor. Due to the flexing of the wire while steering the internal wire had failed.

Dave

how exactly did you find out that that was the problem, and what did you do to fix it...did you change the whole wire? chop out the bad section and splice in something new? just change the terminal?

I’m not sure how real this is, or if it’s quantifiable, but I seem to notice that more often than not the ABS light comes on in the morning. Basically it always comes on when leave for work, but in the evening, when I drive home it almost never comes on. How is that even remotely possible? I’m going to be changing my front brake pads tomorrow morning so I’ll take advantage of the downed car to clean the ABS sensors and check the electrical leads to them.

At first I didn’t believe that the ABS was truly deactivated when that light was on. An intentional “emergency” stop at a relatively slow speed proved me wrong….and left a cloud of smoke rising. Just to be clear, when the ABS light is on…THE ABS SYSTEM WILL NOT FUNTION! I find that to be truly disturbing and frankly unacceptable. Not having ABS is not an option. I’ve gotta fix this electrical gremlin.

My ABS light has been coming on intermitentlyever since I changed to snows. I used the alloy rims from the C-Class to use on my 94 E320. This might be the cause as they fit but stick out a little because they weren't designed for this car. It will be interesting to see if the light comes on when I switch back to my regular wheels.