Hello , Here to answer automotive questions and make you feel comfortable and become familiar with your product.
There is an AM antennae module found behind the trim.
Is the car an avant or sedan?
You can remove the radio and disconnect the antennae from the rear and insert a wire that acts as the antennae removing the cables and booster from the system. This will quickly let you know if it is a radio or wiring fault.
It's a sedan.
hold on, maybe I didn't make it clear that the FM stations work fine, it's just the AM that's cut out.
yes I understand the scenario. There is an AM booster in the rear trim that may have failed causing no AM reception. There may be a cracked circuit board inside.
You must check that the radio 1st is working as design.
remove the radio and disconnect the antennae from the rear and insert a wire that acts as the antennae removing the cables and booster from the system.
This will quickly let you know if it is a radio or wiring fault. You must remove the radio from the diagnosis 1st then move onto checking the AM module.
Sorry, I need more help -
remove the radio, how? (not in the original "operating instructions")
then I find the antennae, disconnect it - sounds easy - and "insert a wire"? Just any old wire, how long should it be? "removing the cables and booster", how do I do that?
but remember, FM works fine. So doesn't it sound like I can skip all this, and just move on to "checking the AM module" ? If the AM booster has failed, what then?
You will need a special set of radio removal tools to pull out the radio.
Remove the antennae for AM a small light brown connector and insert it into the tiny hole. This will act as an antennae. If you get reception then the radio is fine and the problem lies somewhere in the harness or control module.
There are 2 coaxial antennae connections. One for FM and one for AM. We know the FM works. It is the Bigger coaxial antennae. Do not remove the wrong one.
We will move on to the booster check when you are ready for that part.
OK, that's helpful info.
I don't think I'll get into this, we're about to sell the car and I just hoped I could fix this little problem - but I can sell it without the AM radio, will pass along your answer to the new owner (who can then buy the special radio removal tool, and do the first diagnostics) . . . "booster check" or "control module" next?
(Know anybody in the NYC area who'd like to buy a 2002 Quattro, kept in garage and rarely used, 56000 miles?)