ABS pump has gone mental...

[Leavon 0]

Last night as I was driving the car suddenly made a really loud grinding/whirring noise and kicked my foot off the brake pedal, I wasn't far from home so I had a short but scary drive back (made more worrying by the fact that the last grinding noise was my rear engine mount failing and destroying the Drive shaft coupling :pale: ).The noise persisted and there was no "feel" to the pedal, it was either off or on and each time it was depressed it would kick your foot off again. The weirdest thing was that even with the ignition off the ABS pump continued to grind away until I disconnected the battery.

 

I did a searchy but couldn't find any other incidence of this, has anyone got any ideas what it might be? Also is it poss to disconnect the ABS and drive the car normally?

 

Hope someone can shed some light.

[blue95 0]

Can you just not umplug the ABS unit (there is a small connector to the right of it, in the engine bay)

[Kevin Bacon 5]

First thing I'd check is the pedal position sensor. VAG-COM ABS, it'll tell you if it's dead or not.

[dr_mat 0]

Yeah one or more sensors going. VAG-COM it.

[Leavon 0]

I don't have access to Vag-com and I don't have a laptop to put it on so it looks like I'm gonna have to limp it to a garage.

I thought maybe some sort of switch has gone, hence the pump making a grinding noise even with the ignition off. It only shuts off when I disconnect the battery.

Can anyone recommend a decent code reader under £200? I'm keen to try and at least ascertain the nature of the fault myself.

[dr_mat 0]

That's really weird, can't imagine the ABS having a permanent live when the ignition is off, so maybe your ignition switch is faulty too .. ?

Does the dash ABS lamp light up?

Open the bonnet and disconnect one of the ABS sensor lines (runs over the top of the suspension turrets, there's a handy little inline connector on each one). That should totally disable the ABS because it will have a solid fail on one of the sensors. If it doesn't .. you might need a new ABS ECU.

[Leavon 0]

Okay, thanks Dr_Mat I'll give that a try tonight. The ABS light had been on for a couple of days prior to this happening so I knew that something was up, just wasn't expecting it to be such a catastrophic fail of the system. I've also had a mystery power drain on the battery of late, ie. if you leave the car for more than 3 days it won't start so I'm thinking the permanently switched ABS may be related.

I think I'm gonna bite the bullet and get a cheapo lap top and copy of VAG-COM, the way things have been recently it'll get plenty of use.