ABS fault

[nayto]

Iv got an 01 defender extreme, owned it for a few months now and had no problems with it. Up until yesterday morning when i drove out the driveway, the TC and ABS lights came on and tryed putting my brakes on doing 40km/h!
I've read a whole heap of threads on here about the 3 Amigos etc already, (most seem to be on discoverys) and seems to be a common problem. A VERY dangerous problem in my opinion. As i was trying to pull over off the main road, the TC was working that hard that it stalled the car whilst still on the road. Luckily there was on cars coming up behind me.
Anyways, i pulled the fuse so it was drivable and went to Newcastle like i had planned, stopped off at workshop who deals in Landrovers and they plugged in an told me it was the Left front ABS sensor. New sensor is $300 odd! I didnt get a new sensor yet as i thought id look into the problem a bit more.
Id imagine that because the ABS is factory fitted, its illegal to disable it?
Is it a hard job to remove the sensor and test it and the wiring with a multimeter?
Also can anyone recommend who sells sensors for any cheaper? Seems like a lot of money for what im guessing is magnetic pickup sensor? Iread that brake squeal can set off the fault.....how is that possible? Does the dust get into the sensor or pickup? Mine squeals lots, very annoying.....:mad:
Any helpful comments will be appreciated.

[justinc]

Nayto,

The most likely problem is the sensor, ALTHOUGH excessive air gap can set it off. If you look at the top of the front swivel housing, there is a wire going into the middle of the top swivel pin itself, You will notice it has a plastic 'cap' that the wire itself disappears into, that is the sensor body. Get a large flat bladed screwdriver and carefully tap the sensor body downward into the swivel housing with the heel of you hand on the screwdriver handle, not really hard but firmly. You may feel it move in a little. This is setting the sensor, and when you drive the vehicle the sensor ring inside on the CV joint will knock the sensor back off a little. That is the 'air gap'.
The air gap can be excessive if your wheel bearings or swivel preloads are incorrect, causing more knock back of the sensor, introducing a fault.

It is worthwhile doing this first, but you may still need a sensor. And By the way, $300 is a very good price. RRP is well over $400:(

JC

[nayto]

Thanks justin, will doing that clear the fault or do i have to get someone with a computer to do it again?
I pulled the sensor out just before, im guessing there is supposed to be grease in that cavity yes?

[justinc]

Nayto,

Yes, there is supposed to be grease in there:eek:

When refitting the sensor, you'll see what I meen by tapping it in to touch the sensor ring.

The fault should clear if it is only a wheel sensor when driven a short distance. I have had one that didn't, but I tried disconnecting and reconnecting the battery for a few minutes and that did the trick.

I'm not sure there is a code clearing procedure for hard codes except via diagnostic computer interrogation.


JC

[nayto]

Thanks Justin, yeh i wasnt sure if it was supposed to be grease or oil in that part.
I did what you said and it worked! Cleared the code too.
Thanks again, very glad i didnt listen to the bloke at the workshop and buy a new sensor.

[justinc]

Thanks Justin, yeh i wasnt sure if it was supposed to be grease or oil in that part.
I did what you said and it worked! Cleared the code too.
Thanks again, very glad i didnt listen to the bloke at the workshop and buy a new sensor.

Glad all is OK:)

In all fairness to the workshop, it may depend on the equipment they are using. When reading the sensor fault codes on my Rovacom, they can come up with 'excessive air gap' and 'Wheel sensor open circuit' so could be either. I ALWAYS check airgap first for obvious reasons, and if doesn't fix then yes, sensor will be required.
Give it a week or so, if no reoccurence then you should be fine:)

JC

[nayto]

I think it was an Autologic maybe?? Or something like that. Yeh i didnt get to see what it actually came up with on the screen, but glad it was that simple.
Seeing as nanocoms seem to be hard to get hold of, what other computer would you suggest justin? And how much are they!