Traction control light and comm issues mk1 TT

[Dr Sheldon]

Thought I'd try once more, but now vagcom cannot communicate with the haldex. Other modules connected fine (engine and abs).

Really starting to think the haldex controller is bad now.

The efficient way to solve an "intermittent" fault is wait for it to become "permanent"

That can sometimes be achieved by physically bullying the suspected component(s)

 

[Zak99b5]

Well, it scanned just fine twice moments before, even doing the outputs tests. Then "poof" vagcom couldn't connect. I connected to other modules just to make sure it wasn't an issue at the dlc or with the computer, and those were fine. I bet if I try it again, it'll connect. I think I'm seeing the fault "live" as it were.

 

[Dr Sheldon]

Then "poof" vagcom couldn't connect.

Pardon Our Interruption

 

[Zak99b5]

Pardon Our Interruption

Huh?

 

[Zak99b5]

I mean, yes, my mother is dying and we are dealing with funeral homes plus cemeteries, but I don't live in England.

 

[grant@gendan]

Haldex controllers are known for failing on early TT models. They usually fail with an internal software error but some just don't respond.

Lots of upgrade Haldex controllers available these days. Nice excuse for a performance upgrade

 

[Zak99b5]

Haldex controllers are known for failing on early TT models. They usually fail with an internal software error but some just don't respond.

Lots of upgrade Haldex controllers available these days. Nice excuse for a performance upgrade

I'm sort of confidently condemning the haldex controller. Really not much else it could be.

However, I ran a bunch of errands in it yesterday with 4-5 stops, plus my commute to and from work today. And would you know it, no traction control light.

I'll take my time finding a replacement. A lot are under $100 on car-part, and the highest ones there are like $200. About $200 seems the going rate on fleabay. People on marketplace want $400 (shrug). I'd love to get a blue or even orange controller, but those are spendy, and I just bought the car and have done a lot to it (dampers/springs, timing belt, brakes, &c.). So I'm not keen on dropping another chunk o' change on it right now.

 

[Zak99b5]

I know how jinxes work, but I haven't seen a reactions control light in over a week.

 

[Zak99b5]

*traction

 

[Zak99b5]

It's been a while, and I've been driving it daily. The light is off a good bit more often than it's on--seems to be streaky, like 5 days in a row no light, then three in a row where it's on.

Later this week I'm going to order a haldex cm from car-part.com & replace it. I'll follow up with results in a week & a half or so. I already have the fluid & gasket for it.

 

[Zak99b5]

---

Still looking for a haldex controller. Car-part has lots of listings but the 4 places I've called so far all don't have it.

 

[Zak99b5]

Finally got a haldex controller. Had to buy the whole haldex unit to get it.

But the Marketplace dude cut the @&$% wiring going to the controller rather than messing with the clip on top of the diff.

I was so looking forward just to plugging it in and see if VCDS was happy.....

I'm guessing any VW 8-pin D connector will work?

 

[Viking]

Does the plug on your wiring loom not fit? I'm guessing the marketplace seller didn't manage to cut that off?

 

[Zak99b5]

Yeah, seller cut the wiring between the 8-pin plug & the haldex controller. And he knew it was only the controller I wanted.

Contacted him and he apologized, said he'll get the other end out to me asap. We shall see.

I scoured my shed & spare parts stash, but I don't have any 8-pin connectors. Not sure if the haldex side is male or female. I'm guessing VW made all (or most) car-side plugs one, and component side the other, but I guess I'll have to wait.

 

[Zak99b5]

Kinda late but a follow up:

I got a haldex controller used, seller cut the connector off.

I bought a new connector & spliced it to the controller.

Checked channel 125 with oe controller, flicking 0/1 for comms for both the abs & engine canbus connection.

Unplugged the oe connector and plugged in the replacement checked 125 again: steady 1 for both engine & abs comms

I'll have to remove the old & cut its connector off to permanently splice on the replacement then install. Didn't have time to do it today.

Seems a PIA to access but not really hard. Knock on wood.

 

[Zak99b5]

Got the good used controller installed (finally--it was a saga), and all is good.