Have a look at this, most say it was cured with a new diff, but some have been lucky and replaced only the pump
***Copied from VWVortex***
Just wanted to provide an update on my situation and, hopefully, help expand the knowledge base for this issue.
I ended up taking the car to Douglas VW in NJ and after diagnosing the car and finding this code, I had them replace the electric precharge pump and change the fluid. For me, I was lucky enough to have this solve my problem and my all wheel drive finally works again! (Thanks Brian, Patryk, and whoever else worked on the car. Greatest dealership to work with!
)
One thing I noticed while searching for other people with this code. It looks like this AWD code commonly appears in two ways:
01155 - Clutch mechanical
00-04 - Intermittent
-and-
01155 - Clutch mechanical
00-00 - Failure
My code was coming up as intermittent and the pump failed to cycle on while running an output test through VAG COM. The solution to my problem was replacing the pump. The electrical motor must have been binding up, causing the AWD to not function properly, though not completely fail. Therefore, this lead me to believe that the Haldex unit itself was still ok and only the pump motor had to go.
Good luck to anyone else that experiences this problem in the future!
VWVortex.com - AWD Fault Code #01155 - Clutch, Mechanical Malfunction
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