Anyone know how to diagnose a dead CC?

It won't go on.

 

Some have had luck pulling the module from under neath the dash in the glove box area and "re wetting all the solder joints on the PCB" I did that and mine worked for awhile. Perhaps I need to do it again, and actually replace some of the solder joints that look questionable.

 

The glove box module sometimes is the cause, but more often it seems to be the combination switch itself (the lever on the column holding your headlight/cc/wiper controls). It's a known failure on these cars and virtually everyone with an A4 will replace it once or twice (or more). They're $158 new from ECS Tuning, or significantly less from someone second-hand. Replacement involves pulling the airbag and steering wheel - not difficult but it can be unnerving working with airbags so if you do it yourself, make sure you're grounded before handling the yellow bag connector, and you'll need T30 and T55 Torx bits to get the bag and wheel off.

 

Sometimes you will replace just about everything with the cruise and not have any luck . I will be taking mine to an Indie to figure it out now.

 

LMAO give up now. No but really

 

Try some contact cleaner on your cruise control swtich the contacts can get messed up from repetitive use.

 

i always just thought it wasnt supposed to have cruise control.... oops. well i would never use it anyways

 

haha yes its supposed to have cruise control

 

even the manual?

 

Quickest way to check for cruise control is to check the fuse box.