I have been working on this 2006 jetta for years. No one has been able to figure it out and more than one shop gave up on it.
Started out with the a/c stopping then mins later the heater fan would quit.
At time progressed more and more items would shut down. After swapping out many different parts I have narrowed the issue down to the steering control module.
I tried a known good one with no change. Changed out the complete steering column with a known good one and low and behold problem is solved.
I put the original steering control module on the newly installed column and issues returned. Yet the known good steering control module tried on the old column didnt fix the issues. Strange.
Anyhow the new known good column in in the car and the cascade of electrical issues is gone. But I have a new issue.
The transmission doesnt like the new column. Vcds says missing steering angle signal so the trans starts the dash flashing the PND123 indicator and the trans goes out of gear into I assume neutral.
What do I have to do to get the steering angle signal back??