abs light - PeachParts Mercedes-Benz Forum

kanadary · #1 05-02-2002, 06:07 PM

I have had my ABS light come on intermittently in the last few months, now its on all the time, well when ever I stick it into drive and start moving. Does anyone know what it could be and if its something that is relatively cheap to fit. Ken

yhliem · #2 05-02-2002, 08:23 PM

It's probably your ABS ECU. it's located behind the battery. to get to it, pull the battery, and then remove the black plastic cover which is behind the batt. you'll see 2 black boxes behind the cover a little bit towards the center of the car. one is the ignition ECU the other is for the ABS.

However, before you go out and buy a new one, check your ABS sensors. there's one at each front wheel and one on the rear diff. Take them out and clean them and see if that works. If not, go to aurora auto wrecking in Seattle and see if you can pick up an ABS ECU. New they're almost $500 canadian.

euro 287 · #3 05-02-2002, 08:42 PM

Most ABS problems are due to ABS sensors that are not in spec. If one of the sensors is higher or lower than the other then that causes a problem. I have only replaced one ABS control unit and that was on a 190e that was corroded. Your best bet would be to bring it to a shop that has a ABS tester that can check your sensors and give you an accurate diagnosis. Guesses will cost you money, acuurate diagnosis will save you money. Good luck.

yhliem · #4 05-02-2002, 08:50 PM

euro 287

that kinda goes without saying, doesn't it?

euro 287 · #5 05-02-2002, 09:04 PM

that kinda goes without saying, doesn't it?

Sorry didnt understand what that meant?

blackmercedes · #6 05-02-2002, 09:39 PM

ABS light also trips with low voltage, and can be a symptom of charging system problems. I've had the ABS light come on in several of my cars, but it's never been an ABS problem, always charging.

euro 287 · #7 05-02-2002, 09:59 PM

If the ABS light only comes on while the vehicle is in motion it is probably an ABS problem. Most times when you have a charging problem or a bad overvoltage relay it will come on when first started or at times.

brookspw · #8 05-03-2002, 01:11 PM

Does the ABS appear to be malfunctioning? If not, I would BET that it is the OVP.

kanadary · #9 05-03-2002, 01:27 PM

yes, yesterday we had rain after a few days of sunshine, yes, i am talking about the pacific northwest, as weird as that sounds and when i slammed on my brakes to avoid a squirrel, i slide, so i would say the abs is not working. i will check the sensors first then replace the unit behind the battery if feasible. Is there an resistance test or something like that i can use to check the sensor or is the only way to check it with test equipment available at a repair shop? ken

euro 287 · #10 05-03-2002, 08:48 PM

To test the ABS system you must use the ABS tester supplied by bosch or mercedes. We only charge 1 hour for a ABS diagnostic test. That includes connecting tester to the control unit, cheacking all sensor values and testing ABS pump. It is a cheap diagnosis compared to throwing parts at the car. Good luck