# ABS Module replacement - Advice



## red23 (Jan 24, 2015)

Hi All,

So after having had my ABS pump diagnosed as faulty (loss of comms) I have got my hands on a new pump/module with the *exact* same number.

So i tried to disconnect then reconnect the old pump however the same errors appears. I connected the replacement abs/control module unit only by the comms cable and the ABS warning light goes off.

I've been quoted £200 to fit the new unit

So i have few questions as i am tempted to do this myself.

1) The traction control warning light stays on with the new unit but is this because it can detect it is not connected to any brake pipes?
2) Given the ABS unit is relatively easy to access should i just swap the control modules over? 
3) Can i leave the ABS pump connected while i remove the control module?
3) Will coding still be required?

Thanks guys


----------



## red23 (Jan 24, 2015)

anyone?


----------



## MT-V6 (Jan 11, 2015)

Do you mean you left the broken one in and attached the new one by wire only (not fitted)?

If doing so removed some warnings, I'd guess it's probably OK, and the others may need to be reset via VCDS. Some warnings require a short drive too

I can have a look at the workshop manual, try the KB first though as SJP has uploaded a fair few of the guides


----------



## red23 (Jan 24, 2015)

MT-V6 said:


> Do you mean you left the broken one in and attached the new one by wire only (not fitted)?
> 
> If doing so removed some warnings, I'd guess it's probably OK, and the others may need to be reset via VCDS. Some warnings require a short drive too
> 
> I can have a look at the workshop manual, try the KB first though as SJP has uploaded a fair few of the guides


Hi there,

Yeah just loosley connected the new 2nd hand ABS pump/module to test.

It looks like there are two screws holding the mounting bracket on for the pump. Not had any luck in the KB for info its surprisingly hard to find for a mk2.


----------



## John949 (Apr 12, 2017)

I've replaced the ABS unit on a MK1 (and a couple of other cars) but not on a MK 2 but they are similar) - Teves MK6X.

To answer your questions
1) It can't detect fluid in the pipes but it does measure the pressure in the lines, however it does not measure the pedal position so I don't believe it could know if there was no pressure in the brakes when you pressed the pedal. (This means No if you lost my thread).

2) Are you talking about removing the ECU from the pump body? You can't do this on some ABS units without cutting the top off the ECU. On some I believe there are screws. If yours does unscrew then yes you can swap just the electronics box.

3) Do you mean the hydraulic connections? (all the electrical connections are via the ECU). If so then Yes - saves bleeding the hydralic system which is a real pain (see below)

4) Unless the 'specification' of your car matches the donor (quattro, transmission etc.) then yes it will need coding. If you can't communicate with your old ABS then you'll need either an old scan or you'll have to work out the correct coding for your car from its options.

Some ABS errors won't clear unless you reset them. If you need to bleed the ABS unit then you're going to need VCDS (or equivalent) to perform the bleed procedure. Not done it on a MK 2, but on a MK 1 it's a real performance and needs about 3L of brake fluid!


----------



## SwissJetPilot (Apr 27, 2014)

Not sure if this is applicable to your situation, but Ross-Tech has a YouTube instructional video on YouTube for coding the Bosch 5.3 and 5.7 ABS Modules -


----------



## red23 (Jan 24, 2015)

Fantastic info guys.

I'm struggling to free the pump from the car chassis. I can't seem to see what is holding the ABS pump/module in place :?:

I've looked all around the unit and all i can see is there is a bracket which has 2 bolts. Once i loosened these off it was still stuck in place. Any suggestions?

John as above
2) Yes removing the ECU from pump body. I have checked this and it can be easily removed by undoing with a few screws.
3) Yes to save work with the brake lines etc
4) No information of what model of TT the pump/controller was from.


----------



## SwissJetPilot (Apr 27, 2014)

It may be covered in one of the workshop manuals - 
https://www.ttforum.co.uk/forum/viewtop ... &t=1833827


----------



## red23 (Jan 24, 2015)

Excellent thanks.

https://ibb.co/KL84HGr - 1st Page

https://ibb.co/QF03Cn8 - 2nd Page

It's not the clearest or most straight forward to follow or am i just daft [smiley=gossip.gif]

It's detaching "4" from the rubber buffers that i can't do. It's stuck on?

The buffers as shown in this pic are stuck to the unit?

https://i.ebayimg.com/images/g/RO8AAOSw ... -l1600.jpg


----------



## IPG3.6 (Sep 5, 2015)

If they come out of your original unit and your replacement one doesn't have them just transfer them over to the replacement unit then it'll all push in as per oem setup.


----------



## red23 (Jan 24, 2015)

ah ok so to detach the pump from the car i just have to pull really hard? no screws need undone?


----------



## MT-V6 (Jan 11, 2015)

Out of interest, how did the repair go?


----------



## IPG3.6 (Sep 5, 2015)

Because I will also need to do this in the future I've kept this as a reference. This may or may not be helpful to OP but I feel it's relevant.

http://modulemaster.com/rebuilds/instructions/ABS/Audi_TT_ABS.pdf


----------

