W124 ABS Malfunction

[steven moores]

Hi all

Recently my 2.2 ltr '95 W124 coupe auto has developed a fault, showing as a failure on the ABS system. Several times a month the ABS light comes on for long perods of time; sometimes for over a day. When the light is illuminated the system is inoperable and the wheels lock up under hard braking. However, during a journey the light can self-extinguish and the system becomes operable again, enabling braking as intended.

The other relevant item is that when the system becomes inoperable the engine revs drop on tickover from ~600 down to ~ 250 - 300, causing a stall. When being driven at normal road speeds the inoperable system causes a "lumpy"feeling, probably caused by an electrical drain somewhere. However, when the light is extinguished, the car feels right again.

Could the experts on the forum please point me in the right direction to correct this fault or am I destined for a trip to a main dealer?

Many thanks


Steve

 

[television]

Hi Steve and welcome,, both faults point towards the over voltage protection relay,, replace it or solder it up as they get dry joints

 

[steven moores]

Many thanks

Not wanting to sound completely unknowledgable of the engine bay, but perhaps you could point me in the right direction for finding this unit. Is it located near the battery or would I be looking in the wrong place?

Kind regards


Steve

 

[television]

Just behind the battery and it has a fuse on top

 

[The Crooner]

And a black cover over it so you cant see the relay or the fuse on first examination.

 

[steven moores]

Many thanks all.
A job for the weekend when I have daylight.

Kind regards


Steve

 

[television]

If you buy a new one,,you are welcome to post the old one to me and I can test and solder up all free of charge and return it