Awd?
01-05-2009, 09:58 PM
#11
Audi Forum - Posts like an A1
Thread Starter
Join Date: Nov 2008
Location: Alberta
Posts: 47
Re: Awd?
TT01, I am in the exact same position as you: just bought an '02 225TT and I have no RWD with the 01155 DTC. Sucks big time, but I agree with you that calling the previous owner isn't going to result in anything - who on Earth would offer to pay (even partially) for a repair when they can (undetectably) lie and not pay a thing. It's sad to say, but people will rarely not lie when it suits them to do so and they can easily get away with it.
K04, can you tell us how to go about rebuilding the Haldex unit? I've searched the 'net and can't find much other than the Haldex.pdf file, which doesn't have any info. on rebuilding. Also, I can't get the .pdf's in my AESIS to load so that's not any help.
K04, can you tell us how to go about rebuilding the Haldex unit? I've searched the 'net and can't find much other than the Haldex.pdf file, which doesn't have any info. on rebuilding. Also, I can't get the .pdf's in my AESIS to load so that's not any help.
Ah, sorry to hear about that. It is unfortunate for us both. I'll be sure to keep you updated with my situation with any news that may help you out.
01-05-2009, 11:15 PM
#12
Audi Forum - Posts like a Q7
Join Date: Nov 2008
Location: Regina, SK
Posts: 725
Re: Awd?
I'll update you as well.
Here's what I've gleaned thus far:
- Google Haldex.pdf and read it. I'll PM you a link since I can't post URLs yet.
- Check all sensors that feed the Haldex controller; although, usually, a bad sensor will throw a code for it.
- Check connections (broken, oxidized, migrating fluids).
- Run VAG-COM Haldex pump test. Mine failed this, I'm hoping the pump is just crapped out, or better yet, a bad connector.
- Check fluid levels (I'm unsure if low fluids can possibly trigger the clutch DTC by not developing enough pressure to properly operate the clutch).
- I'm also unsure if a faulty controller can trigger the clutch DTC - I read about a couple of people replacing the controller and it working; however, the majority of people just replaced the entire Haldex unit.
It would be very nice to know exactly what issues could possibly trigger the 01155 DTC - I'm unsure whether or not that code can be triggered by low pump pressure (for one of various reasons), and thus the clutch slipping due to insufficient pressure.
Here's what I've gleaned thus far:
- Google Haldex.pdf and read it. I'll PM you a link since I can't post URLs yet.
- Check all sensors that feed the Haldex controller; although, usually, a bad sensor will throw a code for it.
- Check connections (broken, oxidized, migrating fluids).
- Run VAG-COM Haldex pump test. Mine failed this, I'm hoping the pump is just crapped out, or better yet, a bad connector.
- Check fluid levels (I'm unsure if low fluids can possibly trigger the clutch DTC by not developing enough pressure to properly operate the clutch).
- I'm also unsure if a faulty controller can trigger the clutch DTC - I read about a couple of people replacing the controller and it working; however, the majority of people just replaced the entire Haldex unit.
It would be very nice to know exactly what issues could possibly trigger the 01155 DTC - I'm unsure whether or not that code can be triggered by low pump pressure (for one of various reasons), and thus the clutch slipping due to insufficient pressure.
01-08-2009, 09:58 AM
#13
Audi Forum - Posts like a Q7
Join Date: Jan 2008
Location: Central Canada
Posts: 711
Re: Awd?
I'm troubleshooting a failed Haldex on an '01 TT 225 right now.
I ran the VAG Output Tests and they all pass while hoist test demonstrates zero Haldex functionality.
A 65535 code suggests that the controller is not visible on the bus, meaning there is a wire connection problem or failed electronics inside the controller preventing any VAG communication.
The 01155 code suggests one or both of the two most common type of Haldex failure, as in the Controller and or the Oil Pump. The clutch pack rarely fails. Currently looking into the aftermarket Blue Controller for street use for several reasons including the fact that it is cheaper than the replacement OEM controller.
I'm considering going in once and replacing the pump and the controller on this particular TT.
I ran the VAG Output Tests and they all pass while hoist test demonstrates zero Haldex functionality.
A 65535 code suggests that the controller is not visible on the bus, meaning there is a wire connection problem or failed electronics inside the controller preventing any VAG communication.
The 01155 code suggests one or both of the two most common type of Haldex failure, as in the Controller and or the Oil Pump. The clutch pack rarely fails. Currently looking into the aftermarket Blue Controller for street use for several reasons including the fact that it is cheaper than the replacement OEM controller.
I'm considering going in once and replacing the pump and the controller on this particular TT.
01-08-2009, 11:49 AM
#14
Audi Forum - Posts like a Q7
Join Date: Nov 2008
Location: Regina, SK
Posts: 725
Re: Awd?
Thanks K04.
So, can I assume that what you meant by "rebuilt" is replacing the failing components and not actually opening up the Haldex coupling and replacing the internals?
Another question regarding diagnosis: since my car fails the Haldex pump test in VAG-COM, and is not throwing a the 65535 controller code, is it most likely the pump? Is there a way to test the pump on its own (obviously aside from the VAG-COM test, something like actually measuring the output pressure)? Is the 65535 code thrown if the controller itself fails? I suppose both could fail at once, but without having any specific knowledge of this system, I would think the pump is the problem;or, perhaps some internals that regulate the pump pressure. Although, as you said, the pump is a common failure point so that leads me back to the pump.
Do you know of a place to source just the pumps? If I have to replace the controller, I will definitely be going with a Blue or Orange one
So, can I assume that what you meant by "rebuilt" is replacing the failing components and not actually opening up the Haldex coupling and replacing the internals?
Another question regarding diagnosis: since my car fails the Haldex pump test in VAG-COM, and is not throwing a the 65535 controller code, is it most likely the pump? Is there a way to test the pump on its own (obviously aside from the VAG-COM test, something like actually measuring the output pressure)? Is the 65535 code thrown if the controller itself fails? I suppose both could fail at once, but without having any specific knowledge of this system, I would think the pump is the problem;or, perhaps some internals that regulate the pump pressure. Although, as you said, the pump is a common failure point so that leads me back to the pump.
Do you know of a place to source just the pumps? If I have to replace the controller, I will definitely be going with a Blue or Orange one
01-08-2009, 12:23 PM
#15
Audi Forum - Posts like an S4
Join Date: Nov 2008
Location: Vancouver BC
Posts: 277
Re: Awd?
You can look at this as an opportunity to upgrade to the Haldex Performance Controller which senses accelerator pressure engaging the rear wheels before the torque is applied.
HPA Motorsports Inc. - Haldex Controllers
Also it keeps the rear wheels engaged during braking to allow engine braking to apply to all wheels. This whole job will cost you bucks, but you could end up with a better car.
HPA Motorsports Inc. - Haldex Controllers
Also it keeps the rear wheels engaged during braking to allow engine braking to apply to all wheels. This whole job will cost you bucks, but you could end up with a better car.
01-08-2009, 12:45 PM
#16
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Join Date: Nov 2008
Location: Regina, SK
Posts: 725
Re: Awd?
As I stated, I will upgrade the controller if it is malfunctioning; however, I'm a student and won't be dropping $1K on improved AWD biasing until I'm at least at a work term 
Furthermore, the $1K would be better spent on good Summer tires since I don't have a good set yet - I'm probably going Azenis or Dunlop Z1 Star Spec.
FYI, only the Orange Haldex controller keeps the rear engaged while braking.
Furthermore, the $1K would be better spent on good Summer tires since I don't have a good set yet - I'm probably going Azenis or Dunlop Z1 Star Spec.FYI, only the Orange Haldex controller keeps the rear engaged while braking.
01-14-2009, 07:30 AM
#17
Audi Forum - Posts like an A1
Join Date: Jan 2009
Location: Nowhere
Posts: 1
Re: Awd?
Had the same problem with my 02 but the hoist test fooled the techs, rear wheels turned so they thought there was power transfer but I knew there was no way, it was useless in the snow. they finally put it on the ground and took it for a drive in the snow, no power to the rear, hydraulic pump for the haldex was shot,couldn't turn the rear wheels under load, 1300 including installation. Had the car for 3 days before I took it in for this.
At work right now but once I get back to Canada going to go have a talk with the dealership I bought it from. Told them about the lack of rear wheel drive when I noticed it and they said they were willing to do something about it once I found out what the problem was but we'll see.
I feel for you guys, I was pissed when I realized the AWD wasn't working, got stuck in the inlaws driveway first time it snowed, had to back the car up the driveway with my fatherinlaw sitting on the hood for some weight, would have made a great pic.
At work right now but once I get back to Canada going to go have a talk with the dealership I bought it from. Told them about the lack of rear wheel drive when I noticed it and they said they were willing to do something about it once I found out what the problem was but we'll see.
I feel for you guys, I was pissed when I realized the AWD wasn't working, got stuck in the inlaws driveway first time it snowed, had to back the car up the driveway with my fatherinlaw sitting on the hood for some weight, would have made a great pic.
02-04-2009, 02:37 PM
#18
Audi Forum - Posts like an A4
Join Date: Feb 2009
Location: Sudbury, Ontario
Posts: 141
Re: Awd?
TT01, I am in the exact same position as you: just bought an '02 225TT and I have no RWD with the 01155 DTC. Sucks big time, but I agree with you that calling the previous owner isn't going to result in anything - who on Earth would offer to pay (even partially) for a repair when they can (undetectably) lie and not pay a thing. It's sad to say, but people will rarely not lie when it suits them to do so and they can easily get away with it.
K04, can you tell us how to go about rebuilding the Haldex unit? I've searched the 'net and can't find much other than the Haldex.pdf file, which doesn't have any info. on rebuilding. Also, I can't get the .pdf's in my AESIS to load so that's not any help.
K04, can you tell us how to go about rebuilding the Haldex unit? I've searched the 'net and can't find much other than the Haldex.pdf file, which doesn't have any info. on rebuilding. Also, I can't get the .pdf's in my AESIS to load so that's not any help.
Adobe reader like 8.0 and on are beginning to be a nightmare. I use 6.0 Professional and have no issues.
I've seen that fatal mistake many times
Last edited by Ecmbuster; 02-15-2009 at 10:17 PM.
02-04-2009, 02:39 PM
#19
Audi Forum - Posts like an A4
Join Date: Feb 2009
Location: Sudbury, Ontario
Posts: 141
Re: Awd?
As I stated, I will upgrade the controller if it is malfunctioning; however, I'm a student and won't be dropping $1K on improved AWD biasing until I'm at least at a work term Furthermore, the $1K would be better spent on good Summer tires since I don't have a good set yet - I'm probably going Azenis or Dunlop Z1 Star Spec.
FYI, only the Orange Haldex controller keeps the rear engaged while braking.
Furthermore, the $1K would be better spent on good Summer tires since I don't have a good set yet - I'm probably going Azenis or Dunlop Z1 Star Spec.FYI, only the Orange Haldex controller keeps the rear engaged while braking.
Last edited by Ecmbuster; 02-04-2009 at 02:42 PM.
02-04-2009, 02:43 PM
#20
Audi Forum - Posts like an A4
Join Date: Feb 2009
Location: Sudbury, Ontario
Posts: 141
Re: Awd?
Thanks K04.
So, can I assume that what you meant by "rebuilt" is replacing the failing components and not actually opening up the Haldex coupling and replacing the internals?
Another question regarding diagnosis: since my car fails the Haldex pump test in VAG-COM, and is not throwing a the 65535 controller code, is it most likely the pump? Is there a way to test the pump on its own (obviously aside from the VAG-COM test, something like actually measuring the output pressure)? Is the 65535 code thrown if the controller itself fails? I suppose both could fail at once, but without having any specific knowledge of this system, I would think the pump is the problem;or, perhaps some internals that regulate the pump pressure. Although, as you said, the pump is a common failure point so that leads me back to the pump.
Do you know of a place to source just the pumps? If I have to replace the controller, I will definitely be going with a Blue or Orange one
So, can I assume that what you meant by "rebuilt" is replacing the failing components and not actually opening up the Haldex coupling and replacing the internals?
Another question regarding diagnosis: since my car fails the Haldex pump test in VAG-COM, and is not throwing a the 65535 controller code, is it most likely the pump? Is there a way to test the pump on its own (obviously aside from the VAG-COM test, something like actually measuring the output pressure)? Is the 65535 code thrown if the controller itself fails? I suppose both could fail at once, but without having any specific knowledge of this system, I would think the pump is the problem;or, perhaps some internals that regulate the pump pressure. Although, as you said, the pump is a common failure point so that leads me back to the pump.
Do you know of a place to source just the pumps? If I have to replace the controller, I will definitely be going with a Blue or Orange one
