As a dullard, mechanical wise anyway, many of us come here with the hope of enlightenment. Only this WEnd I read thru dozens of threads about the 6 faults my vehicle threw. After all that, someone (I wish I could heap credit were credit is due) mentioned when a battery is going bad the Treg can throw all kinds of faults, often unrelated, as mine seemed. Since it was Sunday, I decided to start there. I estimated to my spouse a 20% chance this would be the issue. I live in Phoenix where the heat was unusual this summer, many >120F (49C) days but had installed a new battery only 11mo ago. Sure enough, it tested bad, and after an exchange, everything magicly improved.
This is a long winded way of saying I (and I'm sure a few others) come here for the pundits who offer info and skills that my Vag-Com can't. I appreciate that; you've saved me a bundle. Maybe you guys that help us dullards should reach around and pat yourselves on the back, since we can't.