PavelB

Hi there.
I have Audi A4 B8 2009 with the next issue.

already replaced door sensors (the defective) scanned all good for now) next it has this...
Can you help me find the left access/start authorization antenna location, i need to replace right antenna, but i don't know where is it. Pictures are welcome! videos are even more magic.

SMac770

What's the rest of the message? If it's short to ground, then the TSB says it's unlikely to be the antenna (located in the left rear door, you have to remove the inside panel) and is a problem in the J393 comfort control module (resistor goes bad or something and lets the transistor fry or something like that).
https://workshop-manuals.com/audi/a4...module/571024/

I had the same problem and replaced my J393 with one off eBay for $99, but still had to have the dealership code it since it involves the immobilizer. One hour labor.
It very will could be your actual antenna module or the wiring between the antenna and J393, but the J393 breaking in this manner is a common issue.

Be sure you verify the valid revisions for your specific VIN before buying one; there's a lot of versions/revisions for the part number and many will not work in your car. I originally had an AH and replaced it with an AS. Current rev for my car is a CS.
https://www.audiatlantaparts.com/p/_...0907064CS.html
As you can see, the price for a new one is nuts when you realize it's about $15 in circuit board parts that is broke.

wolfautoparts.com often has used pulls too, but just verify the specific revision is ok with your VIN per the dealership or such first.
https://www.wolfautoparts.com/2010-2...le-224145.html
But I cannot validate what the CG revision is, parts.audiusa.com doesn't even know the part number. So it's a guess if it would work in my car.

PavelB

Thank you!
But what i am looking for is more like diagram or picture of this freaking antenna in the door and exact it location.
I have no problem to obtain part used or new.
or a part number of it...

SMac770

That's what I'm saying, it's unlikely to be a problem with the antenna, if short to ground is the complete information. As the TSB says.
You need to remove the door panel from the inside of the left rear door. Then the antenna is right there in the middle. There are youtube vids on the door panel removal.

https://www.ecstuning.com/b-genuine-...sor/8k0907247/

If you're going to work on your own Audi, you should pay for a day at erwin.audiusa.com and grab the PDFs for your vehicle. There's too much useful already documented information there to pass over. From the FAQ re Canadian registration:

14. (Canada) The system will not allow me to enter a province name instead of a state.

Canada and Mexico users register by providing only country and zip code. The state list is static and contains only the US states. Therefore it should be left empty. The Canada zip code has the following pattern: A1A 1A1 where A is (nearly) any letter and 1 is any number. Don’t forget the space
between third and fourth character.

PavelB

Thank you.
Here is Amazing description of what i was looking for and All in one place and free:....
https://www.audizine.com/forum/showt...Push-Start-DIY