defender 2006 traction control not working.

[benrover]

I've recently purchased my Defender and love it, I have done a lot 4WD tracks now and have come to conclusion that TC is not working while ABS works on both dirt and tar with no issue!

When I'm crossed up tc blinks on the dash like expected but doesn't seem to apply the brakes on any tyre, had a mate look while I gave it a boot in low 1,2,3 and 4 with the CDL engaged - nothing, no sounds, no dying in the revs, it's just spun the two wheels that had no traction and went no where!

I the only thing I can find manual-wise is http://www.landroverweb.com/Pdf-file...%20Diagram.pdf pg.40-41 ABS

Does anyone know where or what I should look at to fix this issue? - It's been scanned and doesn't have any fault codes.

[djam1]

Put a Nanocom on it and see if the ABS ecu has errors
When crossaxled and you get the flash of the light on the dash do you get a growl from the pump?
You can test the pump from a Nanocom from memory if ABS is working then the system is likely sound
Do you have 2 lights lit on the dash when you start the car one goes out after a short time the other when you reach 7 kmh

[jbe]

As Djam1 said, put a Nanocom on to see if you get any ABS related errors. The way the ABS is designed, I can't see how the ABS can work and the TC not.

[PhilipA]

I must say that my first thought on reading this thread was that The OP may have brake pads that need time to warm like Bendix, or that his braking system has not been bled correctly for a long time.
I have seen a video of a Defender with ABS going across muddy wombat holes and the Traction control does work if working properly.

In my D2 I fitted Lucas pads as they are soft like OE and regularly(well every 2years) bleed my brakes.

If the discs get wet say crossing a river, it takes a few seconds for the discs to dry , then away you go.
My ABS pumps even when I cross a gutter!

Does a Defender have Hill Descent control? If it has then a way to check is get on steep downhill and put into low and away you go.

Regards Philip A
I also exercise my Traction control by using HDC every month or so in my street.

[djam1]

Even old brake fluid can effect it but if the pump isn’t engaging then there is an issue
Nanocom should give a code

[benrover]

OK so I have been to the LR specialist, there is no errors on the diagnostics, the return pump turns on with the tool.

I have put the car on stands so that no wheel was touching the ground and with the engine running check each wheel, the tc lights comes on when each wheel is turned but does not apply the brakes during a "slip condition - tc engagement" !

Keep in mind abs works as expected!

What should I check next? I don't want to pay 3.5K for a new ABS modulator!!

[djam1]

This traction control only works across the axle not diagonally or end to end.
If you jack up the front right hand and the rear left hand tyres and try to drive off does the pump cut in?
You will need to give it a few revs
In this situation the traction control will attempt to put on the front right hand and rear left hand brakes on
As mentioned by Phillip if your pads need to warm up the effectiveness at this stage will be limited
The modulators don't need to be replaced they can be fixed for under 1/3rd of the cost of a new one
Your all 4 wheels off the ground scenario proves little as you wont spin the wheel fast enough to get the brakes to engage

[jbe]

OK, this is getting beyond my expertise with the Wabco ABS (which is limited).

To my knowledge, none of the Td5 defenders has hill descent control, but I could be wrong.

Did the LR specialist comment on your problem at all? Have you googled for similar issues?

I am fairly sure that an ABS pump, modulator or sensor error would throw up a fault code.

What makes you confident that the ABS actually works apart form the dash light.

I am not sure if the car has to drive for a certain distance for the TC to work, i.e. all four wheels spinning at the same peed.

[djam1]

No TD5 Defenders had HDC the system is the same as the early Puma

[benrover]

from the landy specialist...

***** jack up the car so no wheel touching ground and spin each wheel individually!
if the brakes are applied to that wheel when spun tc is working on THAT WHEEL!

Yeah thats right no HDC with the 2006 TD5 defender!

Yes the pump(ABS RETURN PUMP - seen in the diagram above) turns on as I did mention in my post, you can feel it when putting you hand on the ABS unit. No noise it's really quite, as far as I can tell it the computers see wheel slip and knows it's happing just doesn't apply the brakes..

does this mean the pump's seals are shot??? can someone please provide a schematic to the ABS system ?