Installation of Aftermarket DVD GPS Head unit for 2007 Mercedes-Benz ML350

It has always been the desire of many car enthusiasts to own a professionally designed head unit with the best features that will make it stand out alone in the market. Different vehicles have different dashboard so the aftermarket DVD GPS head unit is also different. While installation is also a little different, especially for these cars have fiber optic amplifier. For example, if your car is 2007 Mercedes-Benz ML350 with harmon kardon sound system and fiber optic amplifier, this Mercedes Benz ML GL DVD GPS can fit your car, there are two different installation methods for you to choose.

2007 ml350 factory head unit
2007 Mercedes Benz ml350 factory head unit
Mercedes Benz ML GL DVD GPS Navigation head unit
Mercedes Benz ML GL DVD GPS Navigation head unit

As the aftermarket head unit does not support fiber optic amplifier, so the fiber optic amplifier will not work with the new unit after installation, so what do i have to do?

Firstly, you can splice 8 speaker wires to connect your 8 speaker wires for each car door speaker directly to get sound and by pass the fiber optic amplifier, there’s a long cable with 8 speaker wires included in the pacakge. With this solution you will not need to purchase another amplifier, just check a wiring diagram at the rear of the new DVD GPS head unit and then you can find out 8 speaker wires.

The other method is by connecting the head unit with another amplifier which is non-fiber optical. There’s a lot of work to do for this, so you can try to take it to a professional car stereo shop to install for you. Thanks to N. Elias, who is a professional installer and successfully installed this Mercedes Benz ML GL DVD GPS with another amplifier connected. You can check what he did as below.

It turned out that the harness only powered a few of the speakers so i went to mercedes benzs startekinfo website and got the pin configurarion of the factory harness and i ended up having to cut the wires and rewire them to two 6channel amplifiers that were 600 watts. The sound quality is actually better than the original amp. I completely removed the original amp and installed two aftermarket amps in its place.

There are 12 speakers in all. Front center, left front tweeter, left front midrange, right front tweeter, right front midrange, back left tweeter, back left midrange, back right tweeter, back right midrange, rear left tweeter, rear right tweeter, subwoofer. I looked up from the original harness which wires went to which speaker and matched the front speaker wires up to amp1, then the rear speaker wires to amp2. Then i used the preamp signals from the head unit to go left and right. Front left/right signal went to amp1, rear left/right signal went to amp2. There were also filters on each channel on the amps so for tweeters i only let the higher frequencies pass, the mids some of both and the subwoofer low frequencies. It involved taking apart alot of the vehicle. I luckily also have a mercedes benz star diagnosis unit and was able to reset my seat airbags. The driver and passenger seats both need to be removed to get to the factory amp and battery. I have worked on cars alot but this would probably not be an easy task for a beginner. The headunit has alot more functionality now though than the original and i can add devices easier and cheaper. I will be installing a rearview nightvision camera soon and it is much cheaper than the mercedes solution.

It was successfully installed. I did have to install a new amp, but it turned out be even better than the original in terms of audio quality.

If you still have a question, you can contact us freely.