CTX-3301 | Optic Fiber decoder | Mercedes E class w211 | ClS/S/SL/SLK/CL

The CTX-3301 Optic Fiber Decoder makes it possible to connect an aftermarket Android car radio to the original Bose or Harman Kardon sound system in your Mercedes of construction in a neat and trouble-free manner 2003 to 2008. Thanks to this decoder, which uses the original fiber optic (optical) connection, you do not have to pull cables through the car to the trunk.

This allows you to keep the original amplifier and speakers, while you can enjoy the most modern infotainment functions of an aftermarket car radio.

This optic fiber decoder is suitable for:

Mercedes CLS-class (W219) – 2005 to 2008
Mercedes E-class (W211) – 2003 to 2008
Mercedes S-class (W220) – 2004 to 2006
Mercedes SL Class (W230) – 2005 to 2008
Mercedes SLK Class (W171) – 2005 to 2008
Mercedes CL Class (W215) – 2004 to 2006
Mercedes B-class (W245) – 2005 to 2008

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

How does the car radio Fiber optic decoder work?

The CTX-3301 converts the digital audio signal that runs via the fiber optic from the amplifier to the speakers into a usable signal for an aftermarket radio. This means that the original speakers and amplifier remain fully active, but the audio source is replaced by your new car radio.

This way you can easily switch to Android, CarPlay or other modern systems without any adjustments to the original cabling.

Connecting & Installation

You can usually recognize the fiber optic connection by the orange cable behind the original factory radio. The CTX-3301 is placed behind the aftermarket radio and connected directly to the car radio and the orange fiber cable. No need to run cables to the amplifier in the trunk.

The installation is technically simple, but requires basic knowledge of automotive systems. The decoder comes with an installation manual so that you can carry out installation correctly.

This product is only necessary in combination with Bose or Harman Kardon. Don't have an original premium audio system? Then the CTX-3301 is not necessary.

Frequently Asked Questions (FAQ)

Do all original speakers work with the CTX-3301?
Yes, all original speakers continue to work fully via the fiber optic (optical) channel.

Can I control each speaker separately?
No. Control is via one shared fiber optic channel. Individual speaker control per channel is not possible.

Is the original amplifier retained?
Yes, the original Bose or Harman Kardon amplifier remains fully active.

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

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

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

Can I continue to use 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-3301 is suitable for all common aftermarket Android car radios with RCA audio output.