ABS light on

Hi guys, any thoughts on why my ABS light would be on? Its on its own TC and HDC are working as normal ie come on and go off with ignition.

It looks as though its had rear sensors recently..........

Going to get brain read shortly so will feed that back soon!

Strange... . I suppose the 3 amigos were on before u replaced the rear sensors then the HDC and TC went off.... if u didnt erase the fault codes at that time there might be some hystorical codes stored(one of them recognised as permanent relatred to SVS or TP ) ... i think if u'll plug it in a tester then erase the code the ABS warning will extinguish too.

Here is from RAVE:
After detecting a fault, the SLABS ECU selects an appropriate default strategy which, where possible, retains some operational capability. A shuttle valve switch fault and throttle position signal fault are classified as permanent faults. If a permanent fault is detected, the related warning lamp illumination and default strategies are automatically employed in subsequent ignition cycles, even if the fault is intermittent, until the fault has been rectified and cleared from memory. If a non permanent fault is detected, the related warning lamp illumination and default strategies will only be employed in subsequent ignition cycles if the fault is still present.
After rectification of an ABS sensor fault, the ABS and ETC functions are disabled, and the ABS warning lamp remains illuminated after the lamp check, until vehicle speed exceeds 9.4 mph (15 km/h) (to allow additional checks to be performed).

There are two worst variants, lets hope it's not the case but i put them just for your information:

1. the ECU doesnt get a road speed signal to know that u exceeded 9.4 mph to extinguish the ABS lamp...but u can check that: push ORM switch, wait untill it stops on extended height then go for a ride... if the ECU gets speed signal the car will drop back to normal height when u exceed 18mph.
2. ECU missbehaviour

If the lamp will not extinguish after clearing the fault codes we'll speak again

Well here we go chaps, I had the codes read on a T4, it said front right sensor too large airgap (Historical). So we took the wheel off etc and removed sensor, cleaned the build up of **** out of the reluctor ring and then cleared the fault codes.

Voila no ABS light, now goes out as it should.................BUT..........now when you are driving along it will randomly fire the ABS! I've had to pull the fuse from under the bonnet to get me home, anyone heard of this before now???

Just as a catch up, I didnt replace the rear sensors, it had been done before I bought it but they look very new, I didnt even know it had an ABS fault when I bought it as the light had been covered in the cluster with tape on the back of the panel!! I know the guy I bought it from and hes not that clever (plus he didnt get much use out of it as the compressor died on it so he left it sitting), so it must have been the owner previous to him.:doh:

now when you are driving along it will randomly fire the ABS! I've had to pull the fuse from under the bonnet to get me home, anyone heard of this before now???

Click to expand...

happened to me... disconnect that sensor an ride it so(presuming it's not the hard wired type) then u must see the 3 amigos(maybe together with the red brake warning)... if no codes and it's still doing it i must think that u have an ECU missbehaviour.

have you got a fault reader Dale? Maybe we should go halves on one!!!!!

I've got access to a T4 Dave so dont need to get one. On closer inspection it seems i do have the 3 amigos but some dumb c*nt has taped over the lights on the dash board!!! So, I had the codes read and it was front right ABS sensor too large air gap......we cleared that and it was ABS'ing all by itself so now the light is back on i will get the codes read again and go from there.

Disgoo said:

I've got access to a T4 Dave so dont need to get one. On closer inspection it seems i do have the 3 amigos but some dumb c*nt has taped over the lights on the dash board!!! So, I had the codes read and it was front right ABS sensor too large air gap......we cleared that and it was ABS'ing all by itself so now the light is back on i will get the codes read again and go from there.

Click to expand...

usually when u get "air gap...." fault code is due to wear in the hub bearing which gives a play to the reluctor ring.... i know it's quite expensive but unfortunatelly IMO only a new hub will sort this out

Ok cheers sierrafery, at least i know what to look for know.

When you say play do you mean the bearing??