99.5 a4 2.8Q

im going to get an aftermarket radio to replace the non bose one currently in the car. I've been searching and reading about Vag com and how installing an aftermarket radio may affect the cars diagnosing of potential problems through the diagnostics port.
Now what i've found arent definite answers. one post provided a link with testing this or that. My question is how how do you wire this K-line up when you have an aftermarket radio.
Similiar to like having an in-dash DVD player where you take the parking brake wire and grounding it.

im not to savy with audi's wiring and such but im familiar with installing radios. Would the aftermarket wire harness have a wire to connec that k-line to? Or do I have to ground that wire?
FOr anyone thats installed an aftermarket radio how'd you get around that wire. Sorry if my question is vague.

 

i have no idea but UpstateNYa4 knows. he has a system and i've been able to vag his car fine.

 

You just don't hook it up to the blue wire in the OEM-to-aftermarket radio harness. It was only to be used with the factory radio. Vagcom will just tell you that the radio module is not there. Works the same way on my Passat. What used to happen is that people would connect that blue wire to their power antenna or amp remote lead from the new radio and short out diagnotstic equipment when hooked up to the OBD port. A lot of the new harnesses have a wire loop in that position in the plug or it's missing, IIRC.