My battery and alternator check out as good with the alternator putting out about 23 amps under load. Is that enough to power the ABS? I did a search and read that antilock light will stay on if amperage is not sufficient. Is this my problem or is there another check I need to make? The battery appears to be small in size with cranking amps unkwown but puts out a solid 14.5 volts and the 190e calls for 850 CCA but I've not had a problem with starting, only with this antilock light never going off.

antilock light stays on....

I presume that your ABS light is illuminated whilst driving...
This can be caused by a broken fuse or, most likely, dirty sensors (behind the front rotors/calipers)...

Do you really think it has something to do with the amps?

greetingz,

I would have to agree, I would think that it is rather a fault in the ABS or a blown overvoltage protection relay, but not a faulty alternator.
You should do more checking.

Thanks, yes the ABS light remains on while driving. Fuses are good, will also clean up sensors. How do I check the function of the relay?

Usually when alternators go bad the Antilock is not functioning either. I have seen it happen. My friend has a Pontiac Sunfire, well we were driving around and the ABS light came on, he told me to check the owners manual and it said to turn the car off and turn it back on to reset the ABS. Well he pulled into a parking lot, turned the car off and tried to start it again, well there was a click. His alternator went bad but his charging light never came on. For some reason charging lights never seem to come on in cars, my fathers old cadillac deville had a bad alternator yet no charging light, my mothers corsica had a bad alternator yet no charging light. Maybe just american cars, havent been able to experience it on my MB. Anyhow back on topic, I would guess you need a new OVP.

I checked the connection to the sensors at the strut bushing area and they looked good. Also hooked a high amperage battery in parallel with mine and still the antilock light stays on. The alternator checked out good at the shop with load applied. What else can you diagnose?

When my alternator was failing, the anti-lock brake light would go on then off then on then off again. Flickering and things like that. If it is on all the time it is likely something else as mentioned above. There would also be other signs if the alternator was failing. Dim lights, longer start times, stuff like that.

tryingstar,
The sensors at the strut bushing area can look good, but still need cleaning. Did you take them out to clean them?
The sensor measures the (not) rotating axles at the center of the axle (this should be written differently, but my lack of technical english is ruling here). If there is a lot of iron-related dirt in there, the sensor will not measure anything anymore and the light will be illuminated.

Did you only look, or did you clean the sensors as well?
greetingz,

abs light stays on
 

I have an 86 420 sel it had the same problem, I removed the front abs sensor from the back of the brake mounting area, it is one bolt and a twist to remove it, it is the only sensor that has a wire going to it down there, i cleaned it with brake cleaning spray compound , my light went off and have had no further problems.

Thanks guys, you caught me! I only LOOKED at the connection and the prongs LOOKED clean and non-corrred. I did not go to the sensors itself and LOOK or clean. Will report after that exercize!

OK, last night I pulled the front sensors. Biggest problem was finding a metric allen wrench. Both sensors were horribly dirty and also cleaned out the rotating wheel area with electronic cleaner. Disconnected the negative batt terminal for an hour to reset the computer. Now I'm excted, connected the battery again and....still got the ABS light!!! %&*#@!
Guess I've got to do the rear also. Any other thoughts?

Pulled and cleaned the rear sensor. It too was filthy. It took a DIFFERENT allen wrench from the fronts! Alas, the anti-lock light remains. Looks like it's time to spend money. OVP relay here I come! I'll let you know unless you have any other ideas?

Installed the new OVP relay and the antilock light went out! Also the hard cold starting I had experienced has gurn!! Although the previous OVP did not look bad and the fuse was good, the new OVP had 2 fuses which probably protects what was the bad circuit in my old unit. Hope this thread helps someone else!!