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Mokeylock
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Discussion Starter · #1 ·
I dont understand why my 4Wheel Drive keeps switching off every now and then. It's always because of either the Brake Light Switch going or the Clutch Pedal Switch. I just changed the brake light switch a week ago and now the 4Wheel drive is off again, VAG com is telling me its the clutch pedal switch this time. Are they related? when I change one do I have to change the other? and does anybody know why they keep getting faulty?
 

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Mokeylock
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1,454 Posts
Discussion Starter · #3 ·
I can tell the 4wd is off because the ESP starts to kick in everytime i take off (even slowly when slightly wet). With ESP off, the front wheels spin like mad. Also I was taking a corner in the wet last night and without expecting it the car's front wheels lost grip and I just managed to stop it from hitting the pavement.... With the 4Wheel drive it would have kicked in within a split secondv. But ontop of that i've got the haldex controller and that should make the car a constant all wheel drive but in my openion the brake light switch and clutch pedlswitch are disingaging it.

No body else seems to have the same problem which is making me wonder if there's something else that's damaging the brake and clutch switches.
 

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I cant see anything that would or could damage the brake or clutch switches.

How can u be sure that the Haldex controller you have isn't:

a) faulty

b) fitted incorrectly

by the way,
The haldex controller doesn't make the car constantly 4wd, it makes the rear diff hook up faster and more aggressively, thats all
 

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Mokeylock
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1,454 Posts
Discussion Starter · #5 ·
I cant be sure about the haldex controller but beause i'm having a hard time getting under my car these days, i thought i'll try swapping both brake and clutch switches and see what happenes. If that does nothing then i'll check the haldex controller out.

I was just reading through the Haynes manual and noticed something it says about installing both switch. Apparently after fitting them, you have to get the adjustment of the switches verified electronically using decidicated test equipment (page 4B.4) but this is under the diesel engine section. Does this apply to the 4motion?

I was also wondering if there's a diffrence between a 'brake pedal switch' and 'brake light switch' ? if so which one is the purple one ?

p.s. thanx for clarifying how the haldex works, i didn't actually know that.
 

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Doesn't the hand-brake also disable the 4motion. Maybe it's a faulty sensor? Just a thought...

From what I have read the uprated rear-biased Haldex controller is like night and day
 

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Mokeylock
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1,454 Posts
Discussion Starter · #8 ·
Doesn't the hand-brake also disable the 4motion. Maybe it's a faulty sensor? Just a thought...

From what I have read the uprated rear-biased Haldex controller is like night and day
If the hand-brake disables the 4motion, does this mean that lifting the handbrake when doing a hand brake turn would disable the 4motion ? if so for how long ?
 

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I suppose so, but I don't know for how long - probably long enough! What are you doing handbrake turns in your golf for anyway?

Grow up!
 

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Whats wrong with a good old fashioned handbrake turn ????? Love doing them in the ice as it doesnt wear out ther tyres as much lol
 

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Mokeylock
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1,454 Posts
Discussion Starter · #14 ·
Hear hear,

Handbrake shanannigans are great fun, as long as there done responsibly of course!

Mokeylock.

check out my clicky in my sig! your not alone, also thought you might find this helpful. MAYBE EVEN A STICKY IN THE GEARBOX SECTION!

http://qbn.rdefined.com/HALDEX.pdf

Jambo[Y]
Thanx for that Jambo, i just wrote a reply on that link.

Let me know if you get to the bottom of it
 

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Mokeylock
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1,454 Posts
Discussion Starter · #15 ·
I just made this from the pdf Jambo sent me, hope it helps someone out. Its a diagram of all the sensors the Haldex Controller needs to work.

Haldex Sensors


I've also put it on my website: Haldex Controller
 

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Mokeylock
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1,454 Posts
Discussion Starter · #16 ·
4WD still off, VAG COM shows only 1 error: 65535 which apparently could be the aftermarket haldex controller i'm using at the moment. Planning to refit the oem one and see if everything's back to normal; I'll post the result soon.
 

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Mokeylock
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1,454 Posts
Discussion Starter · #17 ·
4WD still off, VAG COM shows only 1 error: 65535 which apparently could be the aftermarket haldex controller i'm using at the moment. Planning to refit the oem one and see if everything's back to normal; I'll post the result soon.
Result

Re-fit the oem Haldex controller, cleared the codes, went for a drive, ran a test and error code still there!!! (Address 39 Right light: 65535- internal Control Module Memory). I booked the car into VW for tomorrow morning, i told them the problem i have is the "4wd not working"... hope they have better luck than i've had.

One thing i did notice which i never noticed before. Every time i run the diagnostic, the part which says "Address 22 AWD" always comes up in red and has the following message:

"No faults found or DTCs not supported by controller or a communication error occurred"

is this normal? on all the other addresses when there's no fault, all it has is a message saying "No fault code found" without all the other stuff, and it's never in red unless it has found a code... do you guys get the same when running a scan using vagcom? is it normal?
 

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This is the same as i got when my haldex plug was damaged, it means the ecu cant connect to the haldex. Its a bad connection on the haldex plug to the cars loom. double check the plug connection

are going to have to pay or is the car under warrenty

Jambo[Y]
 

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Mokeylock
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1,454 Posts
Discussion Starter · #19 ·
VW just called saying I might need a new rear diff! i'm kinda happy and kinda sad. Great, they found the problem, but I hope the warantee covers it since i only started the cover a week ago! (i think it'll be over ?1,500). I told them to go ahead and contacted my warantee company and they said they'll cover it! umm... ok... let's see how it plays out i guess... will keep you guys updated.
 
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