brake problems
 

Hi, I have a 86 MB 420SEL. Just changed the brakes yesterday with aftermarket pads and rotors, but here is my problem.
I did not know that there were brake pad sensors on this car, so I did not change them. Now the abs light on the dash stays on all the time!! How do I fix this?
I don't have a service manual, and cannot find one.
Any help is appriciated
kris

Replace them, tape them up, or cut them off. Your choice.

Are you sure it's the ABS light? And not the brake lining light? This could be an entirely different problem...

yes its the abs light, comes on sometimes and sometimes it does not.
kris

It's probably an ABS system sensor, not a pad wear sensor issue. The ABS sensors interface with slots on the inside of the front rotors, and replacing the rotors may have disturbed them. Check also to see that the wires are properly routed and clipped in at the right places, and the insulation isn't cut or damaged.

When u replaced the pads u might hit the ABS sensor cable. First locate them and try to clean them and make sure they are connected properly, otherwise install two new ABS sensors. I recommend u to change them even if they r working fine. After arround 10 years they must be replaced in order to function properly.

Typically, the abs sensor gets small metalic particles in the slotted probe. Where do these small metalic particles come from? The Semi metalic brake pads. Cleaning them involves removing the caliper and pads and the hub and rotor. There is a 'tone' wheel on the hub that also gets metalic particles in between the slots.

Here's a link to the W126 service manual.

http://mb.braingears.com/126_DISC2/program/matrix.htm

http://mb.braingears.com/126_DISC2/program/chassis_420SEL.htm