ABS operating, but no light

[75driver]

Hi all,
Just had my 75 CTDI back from mechanic, after he fitted:
- new caliper, rear drivers side
- new rear discs, pads and handbrake shoes on both sides.
- new drivers side front droplink.
Trouble is, the abs is operating too early.
On start up, the abs light comes on and then goes off, as it should.
On medium to strong braking, I can feel & hear something like the abs kicking in. The pedal pulses a bit, but not as strongly as "full" abs operation.
Feels like a bit of trapped air moving??No abs lights come on, or faults logged, so assume abs is operating correctly.
Mechanic has
- rebled the brakes. (Pumped up from connection at brakes back up to reservoir).
- replaced one of the rear sensors, as the end of the sensor was pitted.
- checked the diameter of the new caliper pot was same as the old one.
Still does the same.
Any ideas?
- Warped discs? (Not yet checked).

[75driver]

Wee bump...
I'm open to any suggestions.😄

[trikey]

Dodgy rear wheel bearing(s)

[klarzy]

file the ABS sensor seat down a bit and get the sensor tip a tad closer to the reluctor ring in the bearing...

[freck]

I doubt it's the ABS operating as its a very positive action and doesn't partially work. The system would most likely show a fault too if there was a component broken.

I take it that you didn't notice these symptoms before the work was done? If not, then the most likely thing is that the new parts haven't been fitted correctly or something has been damaged when the work was done. :shrug:
I'd be looking to see if the new discs are seated correctly, pads fitted right etc.

I hope you've not paid for the new sensor either, there won't have been anything wrong with the old one if no fault light was on......****** garages! :duh: :D

[trikey]

I doubt it's the ABS operating as its a very positive action and doesn't partially work. The system would most likely show a fault too if there was a component broken.


Not always, the light doesn't illuminate with this problem, it doesn't store a fault code either, you can only see the fluctuation by running live data on T4 when driving the car, you can see a difference on the readouts that will point to one of the wheels being at fault, its usually the rear wheel bearing.

[cbr1100xx]

had something similar on a rover 414 so not sure if its the same system but mine turned out to be the abs ring on the driveshaft had broken due to rust , this gives the system the idea the that wheel is locked and operates the abs which is felt as a pulsing through the peddle , 2 options to fix--complete cv joint with ring or fleabay and buy just the ring for a few pounds , fitting is quite simple , remove driveshaft from hub , knock the broken ring off , clean the area and tap the new ring on square , hope this helps