# Haldex not working



## malstt (Apr 18, 2007)

I have noticed recently in the icy conditions that my car was wheel spinning more than usual, My first thoughts was Haldex not working. Had a VAGCOM scan done and it came back clear. After doing a bit research I had the fuse checked and the earth lead checked. Fuse was ok but earth lead snapped. Excellent I thought, cheap repair. Fitted a new one and still the rear wheels won't drive. [smiley=bigcry.gif] Looks like I may need a new rear diff. Anything else I can check or try ?


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## FRAX (Jul 21, 2013)

Check it is topped up with the correct grease, this may mean you will have to replace it as it will run out if there is any in there when you remove the plug.


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## malstt (Apr 18, 2007)

Thanks, Had the Haldex oil and filter changed about 4 month ago, so that should be fine.


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## FRAX (Jul 21, 2013)

Have a look at this it may help.
viewtopic.php?f=2&t=111744&start=15


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## 3TT3 (Aug 30, 2014)

I believe (have read ) you can check the diff,for metal bits just by removing the drain plug.
When you checked the fuse and it was ok, take it out altogether to make sure its the same no rear drive,with fuse in or out.

All 4 wheels off ground(on stands) all wheels should spin..,I think I saw on youtube.

This is something plagarised from another forum 

_How to Check if your 4Motion/Quattro is working:

This applies to the following cars: VW MKIV Golf R32, VW MKIV Golf V6 4Motion, Audi TT 225 Quattro, Audi A3 1.8t Quattro, Audi S3 1.8t Quattro, Skoda Octavia 4wd. This will also apply to other cars that use the Haldex 4 Wheel Drive system.

The following items can cause your Haldex All Wheel Drive to be not working. Double check all these. Some require the car to be lifted off the ground.

1: Fuse 31, 5amp
2: Earth on Differential
3: 0.7 amps of Power to the Controller
4: Brake Light Switch
5: Handbrake Switch
6: Haldex Oil and Filter
7: Differential Oil
8: ABS Sensors
9: ABS Master Control
10: Haldex Controller
11: Haldex PreCharge Pump
12: Differential

As you can see, theres a lot of factors involved with the 4motion working or not.

With Car on Ground:

Check the fuse first its the top middle fuse (large blade fuses) should be 5amps, if its higher then replace with 5amp blade fuse.

Connect up VAG-COM and using the measuring blocks you can see if certain things are working for the controller. Temps should be room temperature to start off with. The Power should be 0.7 watts or apps or volts, not sure but that figure which ever it is. Its been a while

Also, with vag-com, you can check the pump with output tests. This is better doing with the car off the ground.

Do a hard launch, if you get front wheel spin, then no power is being delivered to the rear

If you get a grinding noise, then the differential is at fault, where the pinion has moved and locked both the rear wheels.

With Car off Ground (All 4 wheels):

With vag-com, you can check the pump with output tests. This is better doing with the car off the ground.

Can you hear the pump/controller activate once you start the car? if not, then its the controller/precharge pump.

Check that the propellor shaft is moving. This way you can eliminate the front differential.

Start car, put it in 1st, then second like you normally do while driving and let the wheels spin, If all 4 wheels spin, then something is wrong with the differential/precharge pump. Not enough pressure/lock is being applied. This can also be the controller. With this, change the filter/oil for the haldex and the differential. This may solve the problem.

If just the fronts spin or 3 wheels spin, double check that the drive shafts are moving or not. If the prop shaft is moving and the driveshafts are moving but not the wheels, then your drive shaft is buggered._


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## outdoor stevie (Nov 24, 2013)

Find a place where the front wheels will slip and transfer load to the rears, a slight uphill grass slope is ideal and even better if it's wet so it is easy for the fronts to slip at low speed you don't need to drive fast as you will find out very quickly if the rears are not working, or wait a day or two for the snow to come and check then at least then you'll know either way.

From a fellow north East boy

Cheers stevie


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## malstt (Apr 18, 2007)

Thanks for the info. The rears definatley arent driving Tested up on ramps and no drive to the rear. The prop is turning though.
Outdoor stevie you should pop along to the north east meets.

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## DazWaite (Dec 4, 2012)

Sounds haldex pump related......low fluid? Worn pump? Fuse31?

Have you tried the output test on awd-22 to see if pump cycles on and engages?

You could run an output test and check pump is working okay....

Should be able to hear pump whirring when it's switched on in test and then hear it engage the clutches on next test sequence etc....

Daz


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## malstt (Apr 18, 2007)

Fuse and fluid ok. Vagcom check of controller ok. Havnt tried the output test, will look into it thanks.

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## DazWaite (Dec 4, 2012)

malstt said:


> Fuse and fluid ok. Vagcom check of controller ok. Havnt tried the output test, will look into it thanks.
> 
> Sent from my SM-G900F using Tapatalk


If it is the pump then happy days as it's an easy fix.....just unplug then undo a couple of bolts and replace lol

Plenty of reconditioned ones about for around £100

Daz


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## malstt (Apr 18, 2007)

All working again now ! May have been something sticking as the car had stood for a bit.

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## PeterW (Dec 30, 2014)

hi all

I don't want to start new topic

when you doing haldex outputs test the engine have to be running or not ???
are you able to hear pump when running test ?????

thank you


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