Thread: defender 2006 traction control not working.

Originally Posted by djam1

If the ABS pump is working properly it’s quite noisy if you jam on the brakes on with 2 wheels on the dirt does the ABS violently kick the brake pedal
You said in your previous post that the lights come on but didn’t mention the very noisy pump sounds like it is working maybe with a pump pressure issue or it’s partially seized
I have the Wabco D manual will try to send it to you
Jobson auto electrics in Carlton Melbourne can overhaul the unit for you

Yes lights are on and working as expected! The ABS pump is dead quite, can only tell it's running because I put my hand on it when a power bleed was done with diagnostic tool and when I activated tc by turning one the wheels. I woudn't say the ABS threw my foot of the pedal but the wheels don't lock up on tar or dirt and it feels like ABS is working.

I think the brake pedal actually goes further to the floor when ABS kicks in still no noise either, Im about to put my new steering arm on so once thats done I'll take it for a drive and double check thats the case also I'll pull the ABS fuse too and see if the brakes will lock up and report back.

Originally Posted by benrover

I think the brake pedal actually goes further to the floor when ABS kicks in still no noise either, Im about to put my new steering arm on so once thats done I'll take it for a drive and double check thats the case also I'll pull the ABS fuse too and see if the brakes will lock up and report back.

No noise and the ABS is definitely stopping the wheels from locking, I hit the brakes with and without the fuse to check it. The pedal just feels like clicking under my foot not a big kick.

Might be worth checking the ABS relay. If the contacts are burnt out you can have all sort of weird issues.

After reading the Wabco manual djam1 sent me Dropbox - Wabco D.pdf, I am sure that the pump is the problem!

For anyone who is interested it seems that the ABS can still function even if the return pump is not working, you can see this in the hydraulic schematics, ABS mealy attempts to limit the pressure on each brake by shutting the inlet valve once it detects traction lost on that wheel, it will hold both the inlet/outlet values close for a small time then if the foot is still on the brake and wheels are still de-accelerating it will open the outlet value allowing the fluid to flow through the expander chamber and is pumped into through the suction and pressure valve, then, back into the foot pedals line to increase the pressure at the brake .

I'm willing to bet my bottom dollar that the fact my pedal goes in a smig and not kicking out is proof that this pump has failed..

Has anyone pulled the modulator apart before? is there a pull done schematic available? - I use to rebuild hydraulic rams so i'm sure I can mange to replace some pump seals!

Or otherwise what about just connecting up four switches to each inlet valve, you could manually shut off the wheels that are aren't spinning and force the power to go to wheels with traction, just depressing the brake will make it work!! Thoughts? anyone does this?

I would be concerned about the legalities as it relates to the brakes
Can imagine the weeping and gnashing of teeth if it caused an accident

Ring Ian at Jobsons he fixed mine not related or associated just a customer

European Car Specialist Melbourne, Melbourne CDB, Carlton, Fitzroy | Jobson Electronics

Actually if it is just the pump I think you can rob one from a D2 Modulator as they are very similar, I recall someone doing this in the past

My ABS pump on a 2005 Defender Td5 died a bit more than a year ago. I had a look at swapping it with a complete D2 modulator unit, but was not comfortable with the fact that the outlet ports are labelled in a different order to the Defender. Therefore, an outright swap with a D2 unit was not an option for me. Graeme Cooper here in Sydney split the modulator and used a good pump from a D2 unit and used my defender valve body. Their head mechanic told me that it was not unusual on Defenders due the positioning of the modulator in the engine bay.
Cost me much less than a new unit and it still works fine. If I remember this correctly, my dead ABS pump logged a fault code though.

That sound like the go, I'll ring around for one tomorrow

any idea what a D2 module is worth? do people split them often?

Cheers Im Brisbane based if anyone here know somewhere to call it would be great.