500 SEC ABS ASR fault

[Mcvites69]

Hi guys I've spent a few hours looking in the threads and cannot find a solution. so here goes

I had a mechanic fit a set of lowering spring to my 500 sec , before it drove without fault no warning light at all.

When he was trying to remove one of the rear springs he caught the rear brake line and snapped it clean off, so he replaced the broken brake line, bleed the brakes as normal (didn't touch the ABS ASR module) the brake came back to a great pedal, but now the ABS ASR warning lights are on! When you start the car they go off as they should, but as soon as you drive off they come straight back on :fail

Any ideas guys ??????

 

[BlackC55]

I expect he has damaged the wheel speed sensor or the diff speed sensor too.

 

[gbjeppm]

Definitely a speed sensor issue as Olly says, if all of the lights go out, and then come back on again at low speed.

On mine the rear speed sensor is in the diff, and separate sensors on each wheel in the front.

Would start with checking the wiring for breaks to the one on the diff.

 

[Mcvites69]

Sound I will check them all. Is there a resistance reading for them? Yeah two at front and two in rear diff on my sec.

 

[bolide]

It has two sensors at the rear as it has ASR. The ABS sensors should give a voltage at the connectors when the car is at road speed. From memory it's about a volt. You will be able to get a signal by putting the car in gear on a ramp

MB made a test box with a connectors to plug in between the loom and the ABS unit. If you can use one of those it makes fault-finding very easy

Nick Froome

 

[Mcvites69]

Cheers Dude. Did it test for voltage or resistance on this MB test box?