CTX-3302 | Optic Fiber decoder | Mercedes ML w164 | GL x164 | R Class w251

The CTX-3302 Optical Fiber Decoder makes it possible to a neat and trouble-free aftermarket Android car radio to link to the original Bose or Harman Kardon sound system in your Mercedes. Thanks to this decoder, which uses the original fiber optic (optical) connection, you don't have to no cables to run through the car to the trunk.

This way, you retain the original amplifier and speakers, while still being able to enjoy the latest infotainment features of an aftermarket car radio.

This optical fiber decoder is suitable for:

Mercedes ML-Class (W164) – 2005 to 2011
Mercedes GL-Class (X164) – 2005 to 2011
Mercedes R-Class (W251) – 2005 to 2011

✅ Only suitable for vehicles with Bose or Harman Kardon audio via fiber optic cable (MOST system)

How does the car radio fiber optic decoder work?

The CTX-3302 sets it digital audio signal that runs via the fiber optic cable from the amplifier to the speakers to become a usable signal for an aftermarket radio. As a result, the original speakers and amplifier remain fully active, but the audio source is replaced by your new car radio.

This way, you can seamlessly switch to Android, CarPlay, or other modern systems without any modifications to the original wiring.

Connect & Installation

You can usually recognize the fiber optic connection by the orange cable behind the original factory radio. The CTX-3302 is placed behind the aftermarket radio and connected directly to the car radio and the orange fiber cable. There is no need no cables need to be pulled to the amplifier in the trunk.

The installation is technically simple, but requires basic knowledge of car systems. The decoder comes with clear connection labels.

This product is Only needed in combination with Bose or Harman Kardon. Do you not have an original premium audio system? Then the CTX-3302 is not necessary.

Frequently Asked Questions (FAQ)

Do all original speakers work with the CTX-3302?
Yes, all original speakers continue to function fully via the fiber optic (optical) channel.

Can I control each speaker individually?
No. Control is via a single shared fiber optic channel. Individual speaker control per channel is not possible.

Will the original amplifier be kept?
Yes, the original Bose or Harman Kardon amplifier remains fully active.

Do I need to run cables to the trunk?
No, that is not necessary. The connection is made entirely behind the radio via the fiber optic connection.

Is the decoder suitable for every Mercedes?
No, exclusively for the mentioned models with Bose or Harman Kardon and a MOST fiber system.

Can I connect any aftermarket car radio with this?
Yes, the CTX-3302 is compatible with all common aftermarket Android car radios with an RCA audio output.

Will my original CD changer still work after replacing the radio?
No. If you have an original factory-fitted CD changer from Mercedes, it will no longer function after replacing the original radio.

Can I continue using the original radio antennas?
No, it is not possible to reconnect the original radio antennas to an aftermarket car radio. In that case, we recommend using free digital radio via CarPlay or Android Auto.

Can I connect any aftermarket car radio with this?
Yes, the CTX-3302 is compatible with all common aftermarket Android car radios with an RCA audio output.

Important to know

This article is only necessary when your Mercedes is equipped with a original Bose or Harman Kardon audio system with fiber optic (MOST). Without this system, the decoder is not needed, and a standard connection simply works via speaker cables.