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Tech Article

Audi C5 A6 Symphony Sound System (Stereo unit, Radio) Unlock Code

Last Updated: 04/18/2017

Parts Group: Stereo sound system / radio main unit

This article discusses the Audi Symphony stereo unit for the C5 Audi A6 with the main focus being on entering an unlock code for the unit. If you're not here for the technical analysis but would rather buy a used unit from us, then please select the link below. Our stereo units come with a matching radio code, and are guaranteed to work.

Stereo sound system / radio main unit (Audi Symphony by Bose), as on: C5 A6 1999, C5 A6 2000, C5 A6 2001, Part Number: 4B0035195A

The information herein is based on one of our project cars, a 2000 Audi C5 A6 4.2 V8.

I'm assuming that you have the radio code. It is printed on the radio card that is inside the Sound System Symphony booklet that came with the car originally. If you don't have the code, one option is to contact the dealer. For one of our project cars, that's what I did. They required the car to physically be at the dealership, and they charged me $75 for the code.

As per our local Audi dealer, the radio will permanently self-destruct if the wrong radio code has been entered too many times, so ... I made sure I had the right code, and followed the process carefully. From another opinion on the subject, "permanently" is open to some interpretation but I'm in this case simply passing on what the local Audi dealer told me. What I did:

I turned the key on, and the radio displayed "SAFE." I pressed the P.SCAN and RDBS buttons simultaneously. These aren't simply push buttons: they have a left side and a right side. I chose to press the right side.

The number 1000 displayed. I immediately released the P.SCAN and RDBS buttons. I've read somewhere that if I'd kept them pressed in for long enough, the radio would consider 1000 to be the code I wanted to enter.

I used the leftmost four numbered buttons (1, 2, 3 and 4) to enter the 4-digit radio code. For example, if my code were 7531, then I'd pressed the button with a "1" painted on it, and I'd press it to change the first digit of the display from a "1" to a "2." I'd press it again and it'd display a "3." I'd press it another 4 times and it'd display a "7." Then I'd move on to the button with a "2" painted on it, and I'd press it five times until the second digit displayed a "5" ... and so on.

After the correct 4 digits were all being displayed, I pressed the P.SCAN and RDBS buttons simultaneously as before. The display changed to "SAFE" again, and then was replaced by the frequency of a radio station -- and the radio started to play.