ABS cut in way too soon

[steve_b200]

Hi

I've got a 172 ph1. I've just had all the discs and pads changed (official renault parts first time round).

The ABS light now comes on after a very short drive, and the ABS cuts in very early (never did this before). Once the brake pedal felt like it had a brick under it and wouldn't move (my wife had to use the handbrake to stop hitting the car in front).

The garage have changed the rear discs for a different set and tried the old ones on again with no effect. Apparently the rears are the only part of changing discs that goes near the ABS.

They have positioned the speed rings in exactly the same position as the originals and they cleaned the speed sensors.

The ecu isn't storing any faults, but they can get a code when the ABS light is on, it says - target of one of the wheels.

The garage have taken the car to Renault slough, they couldn't get any code out of it. They have spoken to Renault london who haven't heard of the problem before but say because the ecu isn't storing faults it may have a knackered ecu (£800 to replace).

If anyone has any suggestions my mechanic would be eternally grateful, its driving him nuts.

Cheers

 

[Rossy197]

ABS ring isnt damaged is it ? Never heard of this before tbh..

Either that if it aint the ABS ring then it could be the ABS sensor ?, Did you do them yourself or get a garage to do the brakes for you ?

Changing discs and pads is piss easy on an RS

 

[Alex H]

Particularly check the front rings. Or maybe a split CV boot mucking up the sensor?

 

[steve_b200]

Thanks for the advice, I'll pass it onto the garage, see if it helps.

 

[bmh.01]

Is the vacuum feed still onto the servo? Very hard pedal sounds like a lack of assistance, probably wouldn't cause abs issues though.

 

[steve_b200]

cheers bmh, just talked to the mechanic, apprarently the pedal goes rock solid, when you let it off and try again it works, but the ABS light goes on then and cuts in early. Looks like there may be some connection.

 

[bmh.01]

I'd also check the actual master cylinder too, may be not giving equal pressure to the two circuits and locking on set up? Something to look at possibly.

 

[mini-valver]

Sounds much like a broken ABS ring until you said the pedal goes rock hard. Possibly knackered the pump when winding the pistons back in at a guess if they are no broken ABS rings.