ABS kicking in

Hi all. My td5 discovery is playing up again. When i'm coming to a stop it feels like the front offside wheel is locking up and the pedal feels like the abs has kicked in. Can anyone give me a clue what to check for? I'll check the basics like stuck caliper etc but i was wondering if there was a common fault happening. it doesn't feel like its binding.
Thanks.

Is it on bumpy surface could be knackered shocks?

It seems to do it at slow speeds on wet tarmac. I'm not convinced that the wheel is locking up but the abs kicks in. I wasn't sure if there is a ring gear type sensor that could be blocked up causing it to think the wheel is locked. I think I need to get someone else to drive it whilst I look what the wheel is doing.

easiest check would be for bald tyres or if they are crap in the wet. have someone watch to see what happens

tyres are all fine. I need to check whats actually happening at the wheel. I'll update when I know what its doing

are the ABS related warning lamps working on self test? ..to make sure it's not a fault present...there is a reluctor ring within the wheel hub which sends the signal to the sensor but it cant be blocked and if it was you should have got a fault warning(3 amigos) ... it could be an ECU missbehaviour though

Get it on diagnostics,it will most likely show a low or erratic output for one of the wheel speed sensors.

eightinavee said:

Get it on diagnostics,it will most likely show a low or erratic output for one of the wheel speed sensors.

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should'nt that trigger the 3 amigos though?

No,not always,as the SLABS is not quite seeing it as a fault - just enough to make the ABS active.You have to see literally hundreds of failures over a long period to see all the ways they can fail.Then when you think you have seen them all - another one comes along....

No warning lights are on.

Rasher said:

No warning lights are on.

Click to expand...

but do they work on self test?... 3 seconds after the ignition is turned on?

Hi Rasher,
Put your location on and there may be someone near you with diagnostics
Griff

They work on self test yes.
I've updated my location. Bakewell Derbyshire.

still having this problem is there a way I can disconnect the abs sensor at the wheel without anything going into any sort of limp mode.

your problem sounds like faulty sensor ,but you can just disconnect wires at connectors rear of inner wings it will drive normally but with lights on

jamesmartin said:

your problem sounds like faulty sensor ,but you can just disconnect wires at connectors rear of inner wings it will drive normally but with lights on

Click to expand...

Hi, I seem to have this same problem. When you say you can unplug the sensors at the rear of the inner wings, does this bypass the ABS and allow the brakes to operate like a standard brake system and if so what implications are there if you leave them unplugged when it comes to an MOT?

Disabling any part of the ABS system is not a good idea.

If the system is not functional for the MOT it will fail the test.

If you have an accident and the system is disabled by you, you're going to be in deep doodoo as Jar Jar Binks said, with the Police and your insurers taking a very close interest in you and what you have done.

Fix the problem, don't live with it!

There are too many people trying to run a Discovery on the cheap as they cannot mend/understand the problems themselves and cannot afford to take it to a dealer. These are 2.2 tonne death traps if you are not very careful.

Remember Nigel Gresham? or has that been forgotten already?

Peter

Thanks for the reply Peter. I totally agree with what you are saying. The reason I'd asked was because I am very limited on garages that seem to know what they are on about where I live. I have had one garage look at it and they stuck some kind of diagnostics system onto it and came up with nothing, but on a regular basis I can press the brake pedal and it goes sort of hard and starts vibrating. I had read somewhere else, but can't remember where, that ABS can be disabled or bypassed to revert back to a conventional brake system. However, as you say it is best put right rather than compromising my insurance and getting involved with the law.

Sorry to be brutal, but if it was your family that got mown down by a badly maintained Discovery, you'd be the first to shout.

Have you got a copy of RAVE?

If you are serious about looking after the vehicle and diagnosing problems, it is a 'must have'.

Plenty of downloads on the net, but make sure you get the right one, there is one for the Disco 1 as well.

Peter

... also with all the sensors disconnected the engine will run worst as the management misses the VSS(vehicle speed signal), especially if it's an auto... and you'll not have any speedometer indication... as said get it fixed, that reverting to non ABS is a D1 thing, if the fault is intermittent it might be something simple, there are some things you can check without tester, E'G resistance of sensors with multimeter in the disconnected plug, it must be between 950-1100 Ohm, also if you suspend the car to be able to run the wheels in air if you measure for AC voltage you must get up to 2 -3V, maybe even more depending on wheel speed as long as the sensor is good, and if the voltage has a linear behaviaour without sudden fluctuations it means the hub is good aswell, you can also check some earths to rule them out,

some info here: http://www.landroverclubvi.com/uploads/2/3/9/8/2398536/troubleshooting_abs-hdc-tc_warning_lamp.pdf


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