Radio Questions Please help if you know the answers.... Thank You guys..

These may be questions for some of you current D/C techs. to inquire to Becker Radio for us... Pretty Please!!!

1. After looking at the wiring schematic of the radio it only sends front right and front left signal to the amplifer. Are these leads already under amplification from the headunit?

2. As stated above the head unit only sends front sound signals to the amp. Does therefore the headunit recognize (auto voltage sense) that the front is only being used and that is why we don't have a fader or.... Does the headunit really come with a limited circuit that does not have a fader control.

3. Does this car have a factory CD changer option from D/C? If so what input block (i.e. wiring harness input pins) does it use on the back of the headunit.

4. Does the headunit have an aux audio option input? and if so what button on the headunit, controls the choice for the input.


Appreciate the help. ChrisG

 

The head unit gives out a typical signal to the amp using only front channels.

In the harness there is only 4 wires (left +,-, and right +,-) The amplifier does all the crossover points and controls the tweeter, mid range, and sub behind the seat for each chanel. There is no fade as there is only one full range set on either side of where you sit. If you wanted front and rear you would have to install additional speakers somewhere and run the wires for it.

I haven't physically looked at the amp, but there was no wire run to the back of the car like in the SLK. I know the SLK has the option for a disc changer, but I don't believe it is available for the crossfire. If someone could look at the amplifier they can see if it has a bus cable to run such a thing. 2nd question would be (will the head unit support a changer?)

No, but if you look around tech mods section, there is a guy selling a piggy back adapter for such a thing. Found that on a MB board. The only other wire on the harness that wasn't usual was a cell phone mute wire. The amplifier has this option and can be wired in to use it.

Finally, after replacing the factory deck, I noticed the low speed low volume is still in tact. It is controlled by the factory amplifier. No speed sensor wire is run to the actual head unit. Just an FYI.

 

Adam help me out here we are on to something... Are these front signal wires amplified by the headunit? Or just low voltage signal wires with no amplification.


I wonder what button on the headunit would control the switching to the Cd changer input.

Can you post the link to the adapter?

Yeah.. the schematic shows the amp connecting to the body control module and ABS controller, so it is converting voltage signal from both controllers, creating a window for the voltage to adjust the gain on the amp.

Still wonder if I connect speakers to the existing wire harness will the fader option appear, and will I have sound.

 

Quite simply, NO. A "fader" on a car stereo is used to "fade" between the front speaker left/right set and the rear speaker left/right set. Like a "balance" adjusts back and forth between left and right speakers. The Crossfire only has one set of left speakers and one set of right speakers, so there's nothing to "fade" between. As was pointed out, the only way you could "fade" is if you installed another set of left and right speakers somewhere.

If you buy a new head unit that has "non-fading" outputs, that would be ideal, unless you plan to install another set of speakers.

 

IS there such a headunit available out there w/o a fader? If so please send me a link for the vendor!!! I would really appreciate it.

The current headunit is only using front speaker leads, however there are still 4 more blank unused pins in the wire harness for rear speakers.

Has anyone tapped these pins off the back side of the headunit to see if they carry signal and if so, does the headunit now sense the leads being used and have a functioning fader available.

I have a hard time thinking that Becker makes a special build radio with a circuit board with only front speaker leads active and no fader control just for this car and the SLK.

 

It is low voltage, however I hooked up my aftermarket radio with the 35w output wires. It just increases power to the amp signal, which requires less volume for more sound. I never go over 20 from zero. I typically set it to around 10-14. Not sure what the max on the deck is. You could always get an adapter to go from RCA off the new deck to two wires. A ground and a positive. Wire this into the harness.


Not sure on this one. Take a look at the deck on the SLK and see if it is the same. I don't remember. See how it changes disc's.

As soon as I get a chance to resize and upload the images again. I still got my web host provider looking to see if they can recover the FAQ's and such Otherwise I have to create them again

Balance will be left to right. Think of the configuration in the car as 2 tower speakers. In the tower you have one tweeter, one mid range, and one woofer. Left and right configuration.

There are no wires going to the amp as it does not support it. It only has outputs for all 6 speakers, 3 on each side.

If you are using an aftermarket deck that has sound staging, set the sound staging to the front of the car. That way it doesn't try to shift some sounds to the rear chanel which isn't in use.