# Generation 4 Haldex Guide



## HaldexMatt

Applicable Vehicles - *Generation 4 - Typically Post 2008* Confirm via ECU part numbers on this page below
Part number can be read via VAGCOM / VCDS etc - OR label on ECU


Audi TT, TTS, TTRS, A3, S3
Seat Altea
Skoda Yeti, Superb
VW Golf 4 Motion R32, GTi, R32
Audi Q3, VW Passat
VW Tiguan, Sharan
Seat Alhambra
VW Transporter

*This guide does not apply to Generation 2 Haldex Vehicles!!!*

System Overview - The system components











Oil pump with strainer gauze "Haldex Clutch Pump (V181)"
Filter cartridge
Pressure Accumulator (a piston with a spring which holds a pre charge pressure for instant demand)
Oil Control solenoid "Valve for Controlling Clutch Operating Angle (N373)"
A wet clutch pack like a motorcycle clutch, which is clamped together with a piston type actuator
ECU which is a slave to the ABS/TC/ESP ECU

Haldex reduced the specification of the Generation 4 Haldex System by ditching the pressure sensor which Generation 2 systems had, this detected how much oil pressure the pump and filter system was delivering. It was a diagnostic sensor, it had no purpose other than to detect system failure. Without this sensor the system is blind to it's pumping/pressure delivery efficiency. Secondly, VW / Audi never designed or manufactured the Generation 4 Haldex system, thus have overlooked it's servicing and maintenance requirements.










When the ABS/TC/ESP ECU detects the front wheels are rotating faster than the rear wheels by the ABS wheel speed sensors, the Haldex ECU is told to engage the Haldex Clutch pack, thus engaging the 4wd system. It is very fast at responding, it typically engages the 4wd system after around 90 degrees of front wheel slippage. It then holds the 4wd system engaged until the Torque request from the Engine ECU drops. The system disengages if the foot brake or the handbrake is engaged.

The Haldex system is not manufactured or designed by VW/Audi group. It has been out sourced from Haldex Drive Train systems. The Haldex ECU is programmed and the PCB customised to specification for VW/Audi group. Although the ECU's look externally identical to Volvo, Landrover, Vauxhall and Ford ECU's, internally they have different areas of the circuit board populated and have different firmware/flash on the micro processor making them talk different communication protocols for different manufacturers.

The mechanical hardware in the Haldex Clutch/coupling is quite robust, and does not suffer from mechanical failure. In the 800 or so VW/Audi vehicles I have been involved with, only 2 vehicles upto now have had mechanical failure, both of which have been modified power upgraded vehicles.

To diagnose and work on Gen 4 Haldex equipped VW/Audi Vehicles, the workshop must use either VAGCOM/VCDS (preferred) or "after market" scanning equipment which can connect directly to the control unit ID "22 - AWD", and can read the live data from the ECU and run the output tests on the "Valve for Controlling Clutch Operating Angle (N373)" and the "Haldex Clutch Pump (V181)". Such equipment would be Launch Pro X431, Autel Maxisys MS908, some of the Snap-On scanning equipment, Bosch KTS, and Delphi/Autocom DS150E. After market equipment named above have various functionalities depending on version and software updates. If your garage of choice has no compatible equipment they are not suitably equipped (and really need to get with the times).










*Typical Failure Types - Pump Failure*

Fault Codes:-
00448 - Haldex Clutch Pump (V181) - 002 - Lower Limit Exceeded - Intermittent
00448 - Haldex Clutch Pump (V181) 011 - Open Circuit - Intermittent
00448 - Haldex Clutch Pump (V181) 011 - Open Circuit - Defective


















Causes:-
The pump runs every 20 seconds or so to keep the system primed, the ECU powers up the motor for 2 seconds and turns off again.
This causes the brushes to wear out, typically this can be proven by running the pump with VAGCOM/VCDS using the output test function.
If the pump will not run, gently tap the pump a few times with something metal, typically the pump will jump back into life. This is not a fix, this proves the pump is defective.
You can test the pump with a multimeter set in the Resistance "ohms" setting, and connect it to the two terminals in the pumps multi plug, polarity does not matter.. A good pump will measure between 5 and 8 ohms. Below or above this spec highlights a defective pump. Bad pumps often read very high resistance values, very low, or open circuit. Connecting 12v to the pump to make it run is an option, but it is far from any kind of conclusive test method. Some pump will be intermittent open circuit, e.g. they test OK some power cycles then test out of spec the next, this is due to worn motor brushes and commutator.
Pumps burn out typically because the filter clogs up with scum. Typically cars clog the filter between 45k and 80k miles. But I have seen a Golf R with just 17k miles on the clock with a clogged filter. There is no set mileage, more down to activation/use of the Haldex clutch pack.
If replacing the pump ALWAYS replace the filter. It is a consumable, and if clogged the new pump will burn out in a short amount of time e.g. weeks/months.

Resolution:-
Replace Filter + Pump + Oil using correct method.


















*Typical Failure Types - Clogged Filter Failure*

Fault Codes:-
02248 - Valve for Controlling Clutch Operating Angle (N373) - Intermittent
01155 - Clutch - 003 - Mechanical Failure - Intermittent

Causes/Diagnosis:-
The clutch pack wear material is suspended in the Haldex coupling oil. Firstly large particles get filtered out by the pre-strainer on the pump, then the finer residue/particles get filtered by the cartridge filter. According to VW/Audi this filter does not exist!!
Because oil is not passing through the filter cartridge, the oil pressure required to clamp the Haldex clutch pack together under load is not being delivered. Thus the clutch pack slips (causing more wear and clogging the filter further!) thus the ABS/ASC/TCS system detects the front wheels are rotating faster than the rears, which should not be possible with the Haldex clutch engaged, thus the fault codes generated are focused on the Clutch and the Control Valve n373.
CAUTION - a Haldex pre change pump V181 which no longer delivers good oil pressure will also give the same symptoms, and typically testing above or below the 5 to 8 ohms resistance specification.
Jumping/skipping wheel when turning tight corners in car parks etc.
A binding sensation when doing tight turns.

Resolution:-
Replace Filter + Oil + Clean pump pre filter. Often replacement pump is required.


















































*Typical Failure Types - ECU Failure*

_Fault Codes:-_
02248 - Valve for Controlling Clutch Operating Angle (N373) - Defective
02248 - Valve for Controlling Clutch Operating Angle (N373) - Intermittent
02248 - Valve for Controlling Clutch Operating Angle (N373) - 012 - Electrical Fault in Circuit
01324 - Control Module for All Wheel Drive (J492) 004 - No Signal/Communication
65535 - Internal Control Module Memory Error 00-10 - Intermittent
16347 - Control Module - EEPROM error - 014 - Defective - Intermittent
00003 - Control Module 014 - Defective - Intermittent / Control module faulty sporadic

_Diagnosis:-_
This can manifest itself in sneaky ways on Generation 4 Haldex vehicles. It can give any of the fault codes above, and even pump fault codes. As it depends which area of the circuit board is either corroded and/or burnt out.
The most simple way to prove the ECU is at fault is to open the ECU up. To do this, cut away all of the black rubberised sealant from the front cover, GENTLY prise off the lid - do not shove anything under the lid - do not scratch the circuit board or components. Then inspect the ECU's circuit board carefully for corrosion or burnt components on the bottom front edge of the circuit board. Around 15% of all Generation 4 Haldex failure cases have been defective ECU's. I can test these ECU's, and many are viable for repair - depending on how bad the burning and/or corrosion is.
Jumping/skipping wheel when turning tight corners in car parks etc.
A binding sensation when doing tight turns.
Burnt electrical smell from the ECU when removed.

_Resolution:-_
Repair or Replace Haldex ECU
Replacing filter and oil is advisable
Often pump/filter is at end of service life too










*How to:- Replace the Filter*


Remove cover from filter housing via the 2 Allen bolts, pull cover off with slip joint pliers.
Clean any salt around the edge of the white nylon retainer using pointed item such as Stanley blade, do not damage the aluminium housing.
Put oil drain tray underneath the filter/pump assembly.








Connect laptop with VAGCOM/VCDS to car, turn on ignition, select "AWD Unit 22" from the "Select Control Module" page.
Select "Output Tests - 03", then keep clicking "Start / Next" until you see "Haldex Clutch Pump (V181) Activate", then click again.
The pump should run, will see a current value in amps in the measure block increase from 0.00 to maybe 2.00.




When you can hear the oil drizzling into the drain tray, then turn off the ignition.
Now go back under the car, the filter retainer will be sticking out by approximately 10mm.
You can now pull the white nylon filter retaining spindle out with some pliers/grips.
Now fish out the freely moving filter cartridge from the hole, maybe use some long nose pliers if your fingers cannot grab it.
Clean out any debris from the housing with blue roll etc.











Drain Haldex oil from drain point as per diagram "labelled B"
*******(If pump is being replaced follow instructions here for pump)********


Insert the new filter cartridge/retainer and plate assembly in one piece, ensure you lubricate the rubber O rings first.
Some force is required to overcome the friction of the O Rings. If this force is getting excessive, clean the aluminium housing of any corrosion using a blade or abrasive, but ensure you plug the housing with blue roll or rags to stop any debris from entering the chamber and clean out afterwards as required.
Overcoming the friction of the first O ring requires force, but to overcome the second O rings friction use the 2 bolts for the filter cover. Gently pull in the filter using both Allen bolts a little at a time.










Ensure drain bolt "labelled B" has been refitted.
Remove fill point bolt "labelled A" - before removing clean out any corrosion from Allen head, ensure Allen key/socket fits correctly with good penetration.
Fill with Haldex high performance coupling oil until fluid is level/over flowing from fill point.

THEN CARRY ON WITH PURGING/BLEEDING THE SYSTEM

Connect laptop with VAGCOM/VCDS to car, turn on ignition, select "AWD Unit 22" from the "Select Control Module" page.
Select "Output Tests - 03", then keep clicking "Start / Next" until you see "Haldex Clutch Pump (V181) Activate", then click again.
Run the Haldex pump for 1 minute, then press next to engage "All wheel drive (AWD) Clutch Engaged" - this opens the valve.
You will hear the air locks being pumped from the system, the pumps tone will fluctuate.
Press next to disengage the Clutch valve, then next to disengage the pump. Keep pressing next to close the window.
Close "22 - AWD" window and turn off ignition.
Now repeat this process further twice until the pump makes a consistent sound indicating air locks have been purged.


Now top up the oil until fluid is level/over flowing from fill point.
Replace fill point bolt "labelled A"
Expect to insert approximately 700ml of oil in total.


Connect laptop with VAGCOM/VCDS to car, turn on ignition, select "AWD Unit 22" from the "Select Control Module" page.
Click on "Fault Codes - 02", clear any remaining fault codes on the unit.

THEN CONTINUE WITH TESTING THE SYSTEM

Test drive the car, find a safe and legal place to launch the car on slippery ground multiple times, ensure the 4wd system is working.
On low performance vehicles you may have to find a grass or other low friction surface to test 4wd system.
After multiple tests of the 4wd system, connect laptop with VAGCOM/VCDS to car, turn on ignition, select "AWD Unit 22" from the "Select Control Module" page.
Click on "Fault Codes - 02", ensure no fault codes have been triggered.

*How to:- Replace the pump*
Follow instructions for filter change, until you reach:-
*******(If pump is being removed follow instructions here for pump)******** Then.&#8230;


Disconnect both electrical connectors on top of haldex ECU
Remove Haldex ECU via 2 Allen bolts
Remove 2 Allen bolts from pump.
Twist pump to break the friction fit of internal rubber O rings.
Withdraw the pump using twisting action while using a thin scraper in the gap as a lever to help withdraw pump from the housing.
Once pump is removed, cut the cable above the pump.
Pull pump cable/connector out from ECU side.
Unlock/unlatch plastic cable clips (x3) on the top/side of haldex coupling.
Clean out any debris from the pump housing.
Lubricate rubber O rings on the new pump assembly.
Fit new pump into housing ensuring the strainer gauze is at the bottom. (correctly rotated)
Feed cable over the top of haldex coupling, clipping cable into existing 3 x cable clips.
Refit haldex ECU, and reconnect both electrical connectors on the ECU.
Continue Filter instructions.

_DEFECTIVE PUMP NOTES:-_ If pump does not work to drive out filter, tap on pump with hammer as the vibrations/shock jumps the motors defective excessively worn brushes into place to allow the motor to run. If this does not work, the pump will need replacing first, then fill with oil, then drive out the filter using method above, then re-fill with oil to correct point. (You may use more oil than is in 1 bottle in this situation)

*Generation 4 Haldex ECU Part Numbers - 
ECU's are not programmed or coded to vehicles and can be swapped plug and play with no problems, side effects or issues.*

Audi TT, TTS, A3, S3
Seat Altea
Skoda Yeti, Superb
VW Golf 4 Motion R32, GTi, R32

0BR907554
0BR907554A
0BR907554B
0BR907554C
0BR598554
0BR598554A
0BR598554B

VW Transporter (note Diff Lock - Not Compatible with other Gen 4 Controllers - Rare)

09N907554A
09N598554
09N598554A

VW Tiguan, Sharan
Seat Alhambra

0AY907554C
0AY907554D
0AY907554E
0AY598554
0AY598554A
0AY598554B
0AY598554C

Audi Q3, VW Passat All Track

0BS907554
0BS907554A
0BS907554B
0BS907554C
0BS598554
0BS598554A

Generation 4 Haldex Pump Part Number - 0AY598549A

Generation 4 Filter Cartridge - Manufacturers Part number HALDEX.111358 - - NO VAG PART NUMBER - NOT AVAILABLE FROM VW / AUDI

Generation 4 Filter kit with seals, spindle and cover - NO VAG PART NUMBER - NOT AVAILABLE FROM VW / AUDI

*From the Author*

Firstly thank you for reading my guide on generation 4 Haldex systems, ensure you read it thoroughly before spending time and money resolving your problem. This is a typical guide, not every system fails in typical ways, every 50 or so cases I have been involved with I get an "anomaly vehicle". These are interesting as it increases my knowledge of the system, but can be time consuming to resolve. Now after around 800 Haldex fitted VAG group cases behind me I hit less and less anomaly vehicles.

I used to run an Automotive Electronics and Diagnostics business based in Congleton called Auto Fault Finder. My first haldex vehicle was a friends Golf R32 which had been at the local VW/Audi specialist, with the recommendation of a complete new mechanical coupling/diff and ECU. Knowing my expertise he left the vehicle with me, where I found a faulty ECU. After this the local garages kept sending all their Haldex vehicles to me, where I would fix them and send them back - like a sub contractor. I then advertised myself as a Haldex specialist - brave statement right there.

Weekly I would get requests to test the ECU's by mail order from all over the UK and Europe, so I developed a one of a kind, custom bench testing rig. I can run the ECU on my test rig to ensure all output and input systems are functioning correctly.

So I moved away from Auto Fault Finder as a "take all" automotive trouble shooting business, and focused entirely on VW/Audi Haldex ECU repairs and mail order parts supply. You will find my website if you google "Haldex Repairs". You will also find my facebook page under the name "Auto Fault Finder".

I have reverse engineered the circuit boards for both Gen 2 and Gen 4 ECU's, I have full dumps of flash and EEPROM data for all the different original part numbers. I have stock of all the required SMD components and an electronics reworking environment to repair and fault find the boards. I also stock pumps, filters and oil, and I try to offer the fastest turn around, dispatch and experienced support possible.

With regards the corporate policy of VW Audi Group, exactly the same filter cartridge is fitted into Volvo, Ford, Land Rover, Vauxhall and other Gen 4 Haldex systems, although they do have a different fitting kit, but the actual filter cartridge itself is EXACTLY the same. Other manufactures sell them as a part, and specify service intervals. VW Audi Groups are sprinkled with some kind of magic fairy dust which makes them last forever..... well hopefully long enough to get the car past the warranty stage I feel. Ford Kuga owners are hitting the same brick wall, the dealerships really have no idea where to start, and have no support from above.

VAG's policy of the filter being "fitted for life" / "non serviceable component" I feel is corporate madness, negligence, or has an ulterior motive. Maybe a mix of all three. Make of it what you wish. Trying to re-educate the dealership - that isn't going to happen from below. What I tell you is directly contradicting what you are told by VW / Audi, and many of the independent VAG specialist who often employ ex dealer techs. Hopefully as time goes on, more and more VW/Audi specialists will catch onto this Haldex game, but at the same time the garage industry is often less than ideal.

You are only ever talking to a technician, a service manager, a parts manager, a store manager etc etc, they didn't develop this stuff, nor do they reverse engineer it, they do their job to one standard or another. If it isn't on ELSAWIN - VAG's in house workshop manual system, they aren't going to do it. And if the part isn't on ETKA - VAG's in house parts diagram/ordering system, they don't know it exists, nor can they order it or supply it. I had a string of emails about 2 years ago with someone middle management up at TPS over supplying these filters, it boiled down to nothing.

There are no after market manufacturer for filters, pump or oil to my knowledge. There is only one factory which makes all of these automotive Haldex components in Hungary, and they make them for all the various car manufactures which use the Haldex branded systems. You can buy a bottle of oil from Volvo, Ford, VAG, Landrover or Vauxhall - they all have very different price tags, a different branded label, but the same blow moulded plastic bottles get filled with exactly the same fluid on the same bottle packing line in Hungary.

I started this at 10am this morning, its now 8:27pm. Not perfect by any stretch of the imagination, but I hope it helps.

Regards, Matt


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## Danny1

Stunning write up Matt, everything that we spoke about before Christmas, I ordered the pump/filter/oil from you to have done at Awesome GTI if you remember. Hopefully people will now believe what I have been saying in the other posts as I said all the info I had came from you! 

Im sure this will help a lot of people, as long as you still sell the parts, I think the forum should support Matt and buy any pumps, filters and oil from him for the support he is giving all of us!

Cheers!


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## bhoy78

Total legend, excellent guide. Thanks for taking the time to write it up and thanks for sorting my haldex in the past, not had any issues since.


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## ScoTTS...

Absolutely brilliant Matt. Very thorough. I'm certain your write up will assist other forum members with future maintenance and troubleshooting.

Hopefully the mods will be able to add this into the knowledge base. [smiley=thumbsup.gif]


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## MT-V6

Very interesting, I think my car is gen 2 but still good to know

Sent from my Nexus 5 using Tapatalk


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## rajanm1

Great write up!
I'm sure many will appreciate it for a long time to come


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## HaldexMatt

Danny1 said:


> Stunning write up Matt, everything that we spoke about before Christmas, I ordered the pump/filter/oil from you to have done at Awesome GTI if you remember. Hopefully people will now believe what I have been saying in the other posts as I said all the info I had came from you!
> 
> Im sure this will help a lot of people, as long as you still sell the parts, I think the forum should support Matt and buy any pumps, filters and oil from him for the support he is giving all of us!
> 
> Cheers!


I think I remember this conversation, was it where they were tell you something about having no filter, then I pointed out that they sell them on their own website  Was that you? Glad you got sorted in the end.


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## Hadgee

Great write up Matt, thanks for answering your phone.
I am looking forward to doing this on my 'VW Passat Alltrack' as soon as the parts arrive.

Atb Hadgee (Ellis)


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## qooqiiu

This will be a huge help to many. Thank you

So is it completely nessasarly to bleed the system after replacing the filter? And would it be detrimental to get the filter out 'another way?


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## qooqiiu

Video is private?


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## HaldexMatt

Doh, video is now published.

It will bleed itself with time, but do not expect the 4wd system to work correctly until all the air has purged from the system.
I have only, and will only use the forced bleed method. You are obviously welcome to take any other method you feel suitable.
It means I can test the fix before I hand the car back over to the customer, some have which have travelled from places such as the Isle Of Man, Glasgow, Newcastle Upon Tyne, Bristol, Portsmouth. I would not want them to have to come back!

As for removing the filter, the easiest way is the pump pushing method. It is also the most risk free.

Pulling them out is difficult as there is nothing really to grab hold of, you just end up with bits of white plastic in your pliers/grips.

I have also had to use crude methods to remove very seized in filters, maybe in total about 5 or so times over approximately 150 filter changes. 
One method is to insert a heavy threaded self tapper into the centre of the white plastic retainer, then use that to pull it out. Done this 3 or 4 times successfully.
If that doesn't work, and you just keep making a bigger and bigger hole with the self tapper another method is to heat up a screw driver until it is glowing red, then push it through the white plastic retainer at a funny angle, wait until the plastic sets again, then use it to twist out the filter, like a permanent spanner. This has saved the day a couple of times.
And if that doesn't work, you can literally carve away a section of the white plastic retainer using the hot screw driver method, until the plastic retainer collapses inwards. I have has to do this only once.

This is why it is important to buy a complete filter kit, not just the cartridge - firstly the rubber O rings should not be used twice, and secondly if you have to make a mess of the filter retainer you are stuck without the parts to finish the job. On top of that it is good to see a brand new filter cover showing the filter has been changed. And lastly penny pinching £20 on cars such as these is not the way to go.


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## Danny1

HaldexMatt said:


> Danny1 said:
> 
> 
> 
> Stunning write up Matt, everything that we spoke about before Christmas, I ordered the pump/filter/oil from you to have done at Awesome GTI if you remember. Hopefully people will now believe what I have been saying in the other posts as I said all the info I had came from you!
> 
> Im sure this will help a lot of people, as long as you still sell the parts, I think the forum should support Matt and buy any pumps, filters and oil from him for the support he is giving all of us!
> 
> Cheers!
> 
> 
> 
> I think I remember this conversation, was it where they were tell you something about having no filter, then I pointed out that they sell them on their own website  Was that you? Glad you got sorted in the end.
Click to expand...

Yeah thats me mate, they did a good job on fitting it all though and all great since!


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## Drakedog84

Nice post, going through my own haldex pump issues.

During my research though I've seen some people changing the AWD fuse for a 5amp one to protect the pump if the filers clog! Any truth in this?


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## Sodde

Thank you Matt for an amazing insight into the Haldex unit and your business. I'll be printing this out for future reference.


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## brittan

What a great comprehensive guide!

I have now added it to the Knowledge Base with a link to this thread so that other posts besides the guide itself are easy to find later.


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## Dieseljuice

Great write up and many thanks. I'd love to print this out but pictures go off page to the right...I'll see how I can print this....sorted.

Finally - where can you get the filter for the pump so I can remove my pump and change it. Will I need more oil as I just did it not so long ago?

Filter I took out had done 20k and was clean and no gunge anywhere like these pictures so I guess pump filter may be ok too and fine until next change at 40k miles or sooner as car only does about 5k/year?


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## ldhxvs

Great write up, this should be a sticky!


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## qooqiiu

Thanks for answering my questions Matt.

Top man!


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## C00P5TT5

Great write up. And now think this has finally settled thing.

One question though. The pictures of the gunked up filters any idea of the mileage the car had done?

Only reason I ask is that I had my haldex oil change last month at 47k and I am wondering if the filter will last until the 60k service for the next one.

Difficult to answer I know and probably a unknown but I thought I would ask.

I do less than 3ka year, do you know if the oil breaks down faster if used more?.....i would assume so?

Be prepared to be the most popular user on the forum :roll:


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## Hadgee

So parts arrived and the job began...

All went well except the filter assembly would not pump out  . I got round this with the large screw in the hole where the lug used to be and levered it out with my adjustable. (Not easy).

Putting the new filter assembly in was worst that taking it out, there was nowhere to put any force behind it to push. :? I got round this by applying pressure by levering and managed to get it to go back in. If you can get 5-8mm longer bolts it could be screwed in then change back to the correct bolts once they could reach the threads. (I couldn't find any but I'm sure it would work).

So all in all new pump, filter and oil.

I was not impressed because VW changed my oil 3000miles ago to the tune of £170 and obviously didn't think to mention the lifetime filter. (why would they) I now know how easy it was!!

Thank you Matt for the concise guide it was a great help and apologies again for disturbing your sunday :roll: whilst you were writing this guide [smiley=book2.gif]


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## r3_tbh

Great article, very helpful!


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## samco77on

Firstly I would say great guide matt.

My fiance has a 2011 TTRS with 45000 miles on the clock.

Recently she has been having a strange problem which seems to be haldex related.

It happens worse the higher the speed, and only when on the throttle slightly, cruising (full throttle is fine).
The car surges, almost feeling like a rotation imbalance, such as prop shaft or wheel balancing. I have done various tests to try and find the route cause of the problem.

When it happens, it stops if you lift off the throttle, apply the footbrake (with your left foot while still maintaining the throttle), gently apply the handbrake (again still on the throttle).
It happens periodically, there is no rhyme or reason to it.

Before I found your guide I had already changed the pump and the haldex oil, Then i found your guide and changed the filter and the oil again, purging it with VCDS. But the problem is still there.

There are no fault codes in any module.

I have data logged using VCDS and the only thing i can see happening is the current on the clutch valve rises slightly, and the V181 pump goes from LO to HI and 0% DC to 82% DC.

I have even unplugged the Haldex ECU and been for a drive and there is no vibration, this shows that the problem isnt rotational, but haldex based.

I thought maybe a wheelspeed sensor could be dropping out and causing false wheel slip calculations, but I have logged wheelspeed sensors and they seem fine, also 'slip control' channel stays at 0.

Any ideas would be great because I am really out of ideas now, I dont want to buy a new haldex unit for the problem to still be there after.


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## samco77on

Does anyone have the contact details for the OP?


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## Sideshow

HaldexMatt said:


> So I moved away from Auto Fault Finder as a "take all" automotive trouble shooting business, and focused entirely on VW/Audi Haldex ECU repairs and mail order parts supply. You will find my website if you google "Haldex Repairs". You will also find my facebook page under the name "Auto Fault Finder".


I believe there is a contact number on the Haldex Repairs site.


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## brittan

samco77on said:


> Does anyone have the contact details for the OP?


 Matt from Auto Fault Finder http://www.autofaultfinder.com/index-9.html


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## qooqiiu

Hadgee said:


> So parts arrived and the job began...
> 
> Putting the new filter assembly in was worst that taking it out, there was nowhere to put any force behind it to push. :? I got round this by applying pressure by levering and managed to get it to go back in. If you can get 5-8mm longer bolts it could be screwed in then change back to the correct bolts once they could reach the threads.


The standard size bolts here are M5 X 25. So an M5 x 30 or maybe 35 would do the job. You would have to be careful to wind them in evenly tho I guess.


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## HaldexMatt

Just came back to sort out the dead links for the images in the post, due to the updates to the http://www.haldexrepairs.co.uk website.

Someone from this forum called me to say the image links were dead. Now fixed.

I'm sure this was copied somewhere else (knowledge base?) on the forum so it might need updating elsewhere.


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## HaldexMatt

Also as a small gesture to the Audi TT forum, here is a discount code for 8% off your orders for the new webshop

audiTTforum8

Http://www.haldexrepairs.co.uk


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## Boris1

Matt
Great write up but even with that it's beyond my realms of capability lying on the garaga floor under the car on axle stands.
Do you offer a fitting service If I were to drive mine to your place and leave it with you?
I have a late 2008 3.2
Thanks


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## TT_Lad

Hi

Great post!! This is my first post and found this while googling it, I've got the locking up/skipping wheel problem. I've stripped the unit , cleaned it and replace the filter etc, but it's still doing it. Could this be to do with the pump not operating correctly?? I have no error codes. If I unplug the haldex the problem goes away so I know the unit isn't seized.


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## bling

HaldexMatt said:


> Also as a small gesture to the Audi TT forum, here is a discount code for 8% off your orders for the new webshop
> 
> audiTTforum8
> 
> Http://www.haldexrepairs.co.uk


it dont work. but you can now use ross8  then you all get 8%


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## IPG3.6

This is such a great post but it's a shame the images are broken 

Googling the URL however shows a wee thumbnail of them - is there any chance they may be re-uploaded locally?


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## SwissJetPilot

Try this one -

*How To: - The Generation 4 Haldex Guide*
https://www.ttforum.co.uk/forum/viewtop ... &t=1496866

.


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