MK20 ABS coding - 1.8t Quattro AJQ

[Twenty_valve]

First time posting on this forum

A quick introduction. Have been into Audis for the past 10+ years (mostly S2s) and recently got myself a little A3 1.8t quattro 180 to replace my current daily. It's pretty ropey, but my plan is to get it tidied up and running a reliable ~250hp. I may do a project thread if it's likely to be of interest on here.

Anyway, it has an ABS fault which has stumped me. It currently doesn't work at all, and VAGCOM won't connect to the control module. I bought the car with this fault and it came supplied with another (used) ABS unit.

I've plugged the new unit into the car to test it (but not yet swapped the brake lines over). VAGCOM connects to the new unit, but it's incorrectly coded to my car.

I have therefore tried recoding the new unit which i understand involves
1. Accessing the ABS controller menu in VAGCOM,
2. Select "login - 11" then entering generic/suggested code 40168
3. Select "Coding -07" and entering in the new soft code
4. Select "Do It!"
5. Check if new code has been accepted in the "Controller Info" main menu
6. Clear codes and rescan

I've tried every soft code I can find online (from this list https://scantooldirect.wordpress.com/2014/07/29/vag-absasc-soft-coding-success/)

Some of these soft codes are accepted (i.e. once entered, the code in the ABS controller menu system changes) while other codes don't seem to be accepted at all. Regardless, none of the codes which are accepted have cured the problem; when you rescan with the new soft code, the same ABS fault code is returned (01044 - Control Module Incorrectly Coded 35-00 --).

Any help would be massively appreciated. Electronics and diagnostics is really my downfall.



Most recent log file attached plus a couple of pics of the car

 

[MPH]

First time posting on this forum

A quick introduction. Have been into Audis for the past 10+ years (mostly S2s) and recently got myself a little A3 1.8t quattro 180 to replace my current daily. It's pretty ropey, but my plan is to get it tidied up and running a reliable ~250hp. I may do a project thread if it's likely to be of interest on here.

Anyway, it has an ABS fault which has stumped me. It currently doesn't work at all, and VAGCOM won't connect to the control module. I bought the car with this fault and it came supplied with another (used) ABS unit.

I've plugged the new unit into the car to test it (but not yet swapped the brake lines over). VAGCOM connects to the new unit, but it's incorrectly coded to my car.

I have therefore tried recoding the new unit which i understand involves
1. Accessing the ABS controller menu in VAGCOM,
2. Select "login - 11" then entering generic/suggested code 40168
3. Select "Coding -07" and entering in the new soft code
4. Select "Do It!"
5. Check if new code has been accepted in the "Controller Info" main menu
6. Clear codes and rescan

I've tried every soft code I can find online (from this list https://scantooldirect.wordpress.com/2014/07/29/vag-absasc-soft-coding-success/)

Some of these soft codes are accepted (i.e. once entered, the code in the ABS controller menu system changes) while other codes don't seem to be accepted at all. Regardless, none of the codes which are accepted have cured the problem; when you rescan with the new soft code, the same ABS fault code is returned (01044 - Control Module Incorrectly Coded 35-00 --).

Any help would be massively appreciated. Electronics and diagnostics is really my downfall.



Most recent log file attached plus a couple of pics of the car

Mine wasn't working for years there's a guy on eBay repairs them been fine ever since I'll send you a link if you want a couple of the solder joints inside get dry and cause the malfunction couldn't be bothered to do it myself though he done such a neat job
https://www.ebay.co.uk/itm/Volvo-AB...-/293609112636?_trksid=p2349624.m46890.l49292 same as our one
Sent from Syknet Global Defence Network

 

[Twenty_valve]

Mine wasn't working for years there's a guy on eBay repairs them been fine ever since I'll send you a link if you want a couple of the solder joints inside get dry and cause the malfunction couldn't be bothered to do it myself though he done such a neat job

Sent from Syknet Global Defence Network

Thanks for your reply. That's interesting, I could look into doing that myself and retain the old ABS unit then.

I would still like to know how to recode my new unit though incase the old one isnt repairable...

 

[hydro s3]

I thought you couldn't code new ones in. It was either get your one fixed or source one with the same part number or some number. I could be completely wrong (which is quite often) but hope you get it sorted.

 

[MPH]

I thought you couldn't code new ones in. It was either get your one fixed or source one with the same part number or some number. I could be completely wrong (which is quite often) but hope you get it sorted.

I do believe you are correct as you do need the same part number on the controller module! switched mine out to test this when the abs was playing up lo and behold no abs light

Sent from Syknet Global Defence Network

 

[Twenty_valve]

Thanks again for replies...

I just went to check part numbers between the 2 pumps, and they are very different (have added a picture of each). So I'm going to attempt repairing the old one or get it refurbished.

I'll add one caveat (I didn't mention this at first to keep things simple)... I was able to intermittently connect to the old (original) ABS unit, and on the occasion it worked, it returned a list of fault codes - including the same one: 01044 - Control Module Incorrectly Coded 35-00

For now I guess I'll put this down to it being faulty already. Hopefully it'll work once it's repaired. I'll post an update regardless

 

[Twenty_valve]

Just realised that there is another part number on the controller underneath... which is probably the relevant one... these are also different but only slightly

Original: 1JO 907 379 AG
New: 1J0 907 379 P

Perhaps the difference is still enough to mean it's not compatible... will have to find out

Update: looking at pumps on eBay, one seller cared to add "Please match the Part No of your ABS module to ours as this part will NOT work if the numbers do not match"

Looks like you guys could be right!!

 

[MPH]

Just realised that there is another part number on the controller underneath... which is probably the relevant one... these are also different but only slightly

Original: 1JO 907 379 AG
New: 1J0 907 379 P

Perhaps the difference is still enough to mean it's not compatible... will have to find out

Update: looking at pumps on eBay, one seller cared to add "Please match the Part No of your ABS module to ours as this part will NOT work if the numbers do not match"

Looks like you guys could be right!!

With the pump itself you should be fine it just needs the controller to match I can send you a link if you wish of how to repair it yourself https://www.ttforum.co.uk/forum/viewtopic.php?f=2&t=662714

Sent from Syknet Global Defence Network

 

[Twenty_valve]

Little update. I'm now confident that non-identical ABS units cannot be interchanged and made to work. You have to find units (or at least controllers) with identical part numbers. Thank you so much for this advice @hydro s3 @MPH

The 2 controllers I had were 1JO 907 379 AG (original) and 1J0 907 379 P (new). So the only difference was the 2 letters, but they were obviously different; 10 vs 8 solenoids, different casing design and pcb/electronics.

So cut the old one open to see if I can repair it... low and behold the same 2 solder joints (from the TT forum link) which go to the plug for the ABS pump were cracked. Soldered them up and re-tested it... BINGO (almost). It's no longer "incorrectly coded" but I now have 3 new codes

00285 - ABS Wheel Speed Sensor, Front Right (G45)
00290 - ABS Wheel Speed Sensor, Rear Left (G46)
01279 - Longitudinal Acceleration Sensor (G251) 57 - 00 Electric Circuit Failure

So hopefully 3 sensors and it'll have working ABS (although slightly concerned that last code might not be an easy fix)

I'll add some pics later

 

[MPH]

Little update. I'm now confident that non-identical ABS units cannot be interchanged and made to work. You have to find units (or at least controllers) with identical part numbers. Thank you so much for this advice @hydro s3 @MPH

The 2 controllers I had were 1JO 907 379 AG (original) and 1J0 907 379 P (new). So the only difference was the 2 letters, but they were obviously different; 10 vs 8 solenoids, different casing design and pcb/electronics.

So cut the old one open to see if I can repair it... low and behold the same 2 solder joints (from the TT forum link) which go to the plug for the ABS pump were cracked. Soldered them up and re-tested it... BINGO (almost). It's no longer "incorrectly coded" but I now have 3 new codes

00285 - ABS Wheel Speed Sensor, Front Right (G45)
00290 - ABS Wheel Speed Sensor, Rear Left (G46)
01279 - Longitudinal Acceleration Sensor (G251) 57 - 00 Electric Circuit Failure

So hopefully 3 sensors and it'll have working ABS (although slightly concerned that last code might not be an easy fix)

I'll add some pics later

Cleared all and rescanned of course bleed the abs with the vcds procedure etc of course looking forward to any updates happy to be of any assistance

Sent from Syknet Global Defence Network

 

[Twenty_valve]

Just thought i'd post an update to complete this thread...

As previously mentioned, I managed to sucessfully clear the code "ABS Control Module Incorrectly Coded" after cutting the module apart and repairing the circuit board (as per the link from TT forum)... following this, I then got 3 new codes; 2 abs sensors and the longitudinal acceleration sensor...

So i bought all 3 sensors (to the tune of approx £65)... the longitudinal acceleration sensor was quick and easy to swap, but both ABS sensors were a real pain. Anyway, i got them both swapped over... connected up VAGCOM and cleared the codes... (drum roll)... now I have 5 codes all 4 ABS sensors plus the longitudinal acceleration sensor.

Beginning to think I have another problem... I started by looking at the multi-pin plug onto the ABS controller which I already noticed had some corrosion (the seal was split so it must have let in some moisture)... So I ground a needle file to a small point and cleaned inside all the pins inside the plug, then did the same to the pins on the control module... plugged it backed together and re-tested... BINGO! no codes and no ABS light. I can therefore assume the plug connections were at fault... and I probably didn't need to replace any of the sensors... but never mind. Looks as though it's fixed.

I'm currently not able to road test the car as I've now ripped the turbo off, but fingers crossed it'll work.

Thanks again for your help

 

[hydro s3]

Brilliant news mate good job. On a plus you won't have to replace ur abs sensors for a while lol.