Hi looking for help. My ABS light came on and garage says I need to replace abs hydraulic modulator unit which I think is same as abs pump or abs control unit? Anyway it's 490 for the new part so would like to fit a 2nd hand part which I thought would be OK but garage says buying 2nd part abs control is worthless because they need coded which is not possible?

Help!

First Welcome to the Forum.

I'm afraid your garage doesn't know what they are talking about! the unit can be coded easily with the VCDS software, but before you go replacing the unit, have a good close look at the fusible links on the top of the battery, as they often crack but appear OK and due to the high current of the ABS pump, this causes a voltage drop to the control unit and this puts on the fail warning light, do you know what the fault codes were ?

If it does need a new pump/control unit try www.stevensvwspares.com as they hold a good stock of Polo parts and are reasonably priced.

Thanks for your reply. I want to try and code it but can you point me in the right direction of the VCDS software as this is not something I have ever used before, how much does it cost? There's all sorts of things to buy/download on http://www.ross-tech.com/index.html

I will check the links but how do I fix this if they are cracked?

Unfortunately I don't know the fault codes, the garage just said they ran the diagnostic check and it said the ABS HYDRAULIC MODULATOR UNIT needs replaced.

In the Haynes manual it just says get it replaced at a VW garage:(

Edited 25 April, 201511 yr by hardspend

To check the links it's best to unbolt them and that way you can get a close look at them, If they are damaged you'll need to get them from VW/TPS Also check the "plug in" blade fuses on the battery as well for corrosion of the contacts.

I can't find the ebay link to the "Chinese copy" of the VCDS HEX-CAN lead that gives you the full functions without buying the Ross Tech licence, but I found this http://www.ebay.co.uk/itm/Rent-a-VCDS-Vag-com-Hex-CAN-USB-Genuine-Ross-tech-Cable-for-RENT-Vw-Audi-Seat-/111543954253?pt=LH_DefaultDomain_3&hash=item19f889ab4dmight be an option ?

There is also a common fault within the ABS unit, again it's to do with a low voltage fault code, there is a guide in the FAQ's about this fault http://www.clubpolo.co.uk/forum/index.php?showtopic=312683it's listed as for the 6N2 but is applicable to yours as well

Thanks again. When I have the VCDS software - do you know what 'coded' actually means? Am I reseting a fault code? The garage mentioned something about needing to know the original car numbers? 11 digit number.

Yes that rental looks good, I think that will be what I do.

Yep read that post earlier when searching google and will definately be checking the fuses!

Edited 26 April, 201511 yr by hardspend

The "coding" tells the ABS control unit what vehicle it's fitted to and yes it's an 11 digit number like " 10110111011" so before you remove the one fitted you make a note of this and then copy it to the new one when fitted, if it comes from another Polo chances are the code will be correct anyway :)

Thanks again, will let you know how I get on. Just trying to find right part and will rent that software.

Also, in the faq section there is a guide for repairing the controller, which is seperate from the pump unit. There are 2 soldered joints the go dry and loose contact to the pump motor. The guide is for the 6n2 but the units are the same for 9n, unless it has ASR/ESP which isn't likely on a 1.4.

I would try the above fuses first as this is the fault 90% of the time. If that turns out to be okay, then I would try clearing the codes and see what comes up again, it may well clear altogether after the fuse contact is cleaned.

If it comes up again as controller error, I would recommend trying the fix in the faq, as at this stage you would be looking at a replacement unit anyway so not much to loose if you go wrong.

If you do go for a replacement unit, get one from the same model and year as the coding will no doubt be the same. You also don't have to change the whole pump unit, the controller part is bolted in with small torx bolts and can be swapped in situ.

Also worth mentioning the plug to the controller itself, this has been known to ingress moisture so removing it and using a contact cleaner or even wd40 ( blow out before refitting) should do the trick in most cases.

hey I finally managed to get a new part and attempted to fit it yesterday which worked ok. Brakes are a bit spongy so I think I need to change brake fluid however I found that my locking wheel nut key has gone.... :x Is it possible to buy a replacement or best just to force them off?