ABS comes on a any speed

[sebasteeno]

As the title says ive a problem with the ABS on my V70 P1. Basically at any speed and any type of breaking the ABS comes on,. All discs and pads have been replaced within the last six months and ive been driving about with the ABS fuse removed which is fine but with my MOT in a couple of months i think its time to get this sorted. Anyway someone mentioned the ABS speed rings (?) on the driveshafts or the sensors, does that sound right?

[Flatout Phil]

It is EXTREMELY LIKELY to be an ABS ECU fault - dry solder joints most often. There are some very comprehensive threads on this common problem. Some dare to do it themselves (see P_fandango) but there is a bloke on ebay who does the repair for £80 (or offers) p&p included.
I first discovered this problem some years ago. ABS light was intermittent, took it to garage who diagnosed rear sensor fault. They replaced rear sensors, problem came back. Sent ABS ECU off, came back, problem solved.
Removal of the unit is simplicity itself. Six torx heads to unscrew, a couple of connectors and bob's your uncle. I know ABS sensors can go wrong, but apparently the ECU can mistakenly indicate a rear sensor fault, when the problem is actually in ECU itself. Computers for you...
Check out the other threads for more details.

[p fandango]

it weren't me, my ABS is & always has been fine. Wobbly Dave usual repairs then for a fee. My opinion is its something more serious tbh, the ECU fault normally just brings the light on. I've never known a system to activate the ABS all the time

[Flatout Phil]

it weren't me, my ABS is & always has been fine. Wobbly Dave usual repairs then for a fee. My opinion is its something more serious tbh, the ECU fault normally just brings the light on. I've never known a system to activate the ABS all the time

Sorry Pedro! Not casting nastursiums there... :redface: I think it must have been WD or someone else. Anyhow, I am a bit confused by the fault description, as to whether it is the classic on for a bit, off for a bit ECU issue, or if it only comes on when the brakes are applied, and then goes off again. My money is that it is the first of the two faults - but the system is not incredibly complicated broken down to individual components so I rekon it is fixable.

[p fandango]

lol no worries mate, i actually want to remove the ABS but thats a later project

[sebasteeno]

Sorry Pedro! Not casting nastursiums there... :redface: I think it must have been WD or someone else. Anyhow, I am a bit confused by the fault description, as to whether it is the classic on for a bit, off for a bit ECU issue, or if it only comes on when the brakes are applied, and then goes off again. My money is that it is the first of the two faults - but the system is not incredibly complicated broken down to individual components so I rekon it is fixable.

All i can describe it as, the brakes seem to apply then go off like ABS does but at all speeds of braking. Its not intermittent, its all the time but as soon as the fuse is out my brakes are perfect. I thought id read somewhere that it can be caused by sensors or the speed rings (if thats what theyre called) as this fault does not sound like the ECU problem that seems very commen.

[p fandango]

not that i know about ABS, but i'd of thought if one of the wheel speed sensors/rings isn't giving a signal then the ECU might think the wheel is locked up/sliding so cut the ABS in to regain control

[sebasteeno]

not that i know about ABS, but i'd of thought if one of the wheel speed sensors/rings isn't giving a signal then the ECU might think the wheel is locked up/sliding so cut the ABS in to regain control
& it does seem to be only coming from one wheel if thats possible

[p fandango]

has the ABS system not thrown any fault codes that you can read to see exactly what is going on?

[Flatout Phil]

I know there is some stuff on the VOC website about cleaning up sensors and speed rings - so probably worth a shufti. Is it a front that is going all the time?

[sebasteeno]

I know there is some stuff on the VOC website about cleaning up sensors and speed rings - so probably worth a shufti. Is it a front that is going all the time?

Yeah seems to be

[Al115]

Different car, but my sister's Fabia did exactly this for a while. The cause was (wait for it) Skoda's pikey hub nut coming undone, the driveshaft slowly slipping out, and the ABS sensor ring eating into the sensor!!!!!! Glad we found it.

Just in case it prompts some thoughts of where to look on yours.