I live in a small rural town with limited resouces when it comes to reliable repair. Here is what happens:


87' 300E

Each time I crank my car and start to drive the anti-lock brake pump goes off several times in a row. It then disables and the anti-lock brake light comes on. I had a guy here in town replace a speed sensor that he said might be the cause. Now in the rear of the car, on the inside, I can hear what sounds like a small electric motor or pump running even when the key is out of the ignition, but the original problem still occurs. This started the day after I picked up my car from the mechanic, and he says that it might be my fuel pump. Sounds like the guy is trying to crawfish me.

Any suggestions?


Help!!!

MH,

I had an ABS issue with my 87 SDL. I'm guessing that Mercedes uses similar parts and technologies across the different size cars, and mine was the same year as yours.

After a little carefull tracing I found the wires from the ABS sensors come up into the engine compartment. There was a connector, then the wire proceeded to the ABS unit. My driver side connector was near the fuse box, and passenger side was in front of the washer tank. There were a pair of wires coming from the front wheels. 1 wire had a flat connector for the brake pad wear sensor and other a round connector for the ABS. Measuring the ABS I found 1 side open and 1 side at 1300 ohms. I had bought a pair of used sensors and they both measured about 1300 ohms as well. Replaced the open one and it was fixed.

Another common reason for the abs malfunction could be dirty sensors. They can be removed fairly easily from the front hubs. I sprayed some brake cleaner in the holes and turned the rotor to clean out the "teeth".

Good luck.
Chuck

These ABS units are dependent on the sensors. I agree with the above post. Use your multimeter and check each sensor. Probably a bad one. What work was done by your mechanic on the occasion of it's failure?