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How to Activate Control of the Rear Speaker Volume
I know that there has been a lot of discussion, frustration, and complaints about the sound system in the R231 SL. On another group, I posted detailed instructions with photos on how to activate the speaker fader control. This will allow you to control the volume of the back speakers without adding any amplifier or changing any wiring. I did this on my SL 550 about eight months ago and it works very well. These instructions only work on MY 2013-2016 pre-facelift R231 SLs with Harman Kardon Logic 7 sound without Apple Car Play.
How Activate the Rear Speaker Volume/Fader Control on the R231 SL with Logic 7 Sound Comand NTG 4.5
Note…This only works on MY 2013-2016 R-231 Pre-facelift SL without Apple Car Play.
1. Enter Engineering Mode...This is performed with the engine off, ignition on, and on the Comand/Audio system number pad under the video screen. Push and Hold the Red Phone hang up button, the number 1 button, and the # symbol button at the same time. Hold all 3 buttons at the same time for approx. 5-10 seconds or until the engineering menu is displayed on the screen.
2. Using the Console Control, scroll down to number 7 (“HW Setting”) Press the console control to select.
3. Using the Console Control, scroll down to 7.7(“HU Parameter”) Press the console Control to select.
4. Rock the Console Control back to scroll all the way down to number 49 (“ Speaker Control”) Note…Rotating the console control will not allow you to scroll through the numbers to this point, rocking the control back will scroll to the proper point. Press the Console Control to select (“Speaker Control”) Scroll down to highlight (“Balance and Fader”) and press the Console Control to select.
5. On the Console Pad press the back button until you return to the (“HU Parameter”) screen and then scroll down to (“End”) and press the Console Control to select to exit the (“Engineering Menu”). The Comand system should reboot at this point. If the system does not reboot, without turning off the ignition, turn the Comand/Audio system off and back on from the button in the center of the volume control under the display screen to register and save the new selection.
Now back on the home screen, scroll to highlight (“Sound”).Along with Treble and Bass, the Balance and Fader control should be on the screen which will allow you to fade more volume to the rear and control the volume of front and back speakers as well as balance from the console control.
The Fader Control now should allow you to control the volume of the front and back speakers. This function works with Logic 7 Surround on or off. The fader settings that you set will be remembered until you change them. Each time that you turn Logic 7 surround on or off though, the speaker fader will need to be readjusted to your preference as it will return to the middle factory set point. I find that for my preference the system seems to sound much better with Logic 7 Surround on and the fader set to (-5) for the front speakers. At least now you can control the volume of all of the speakers.
I would also like to add that I would not recommend changing any of the other settings in the Engineering Menu and there are a lot of them. I am surprised though that Mercedes decided to not have the Fader control active from the factory.
I hope that this helps and Happy Motoring.
Last edited by BBay; Sep 3, 2021 at 12:22 PM.
Reason: unable to upload photos and instructions
Hi, yes I did this in my 2013 SL63 a few weeks ago and it definitely works. However the sound from the rear speakers is very much biased towards treble and is overall at lower volume than the fronts. So whereas there is clearly an improvement, it isn’t breathtaking by any means.
Hi, trying to do this in my mom’s 2016. I got as far as “rock the console back” and tried pushing the console control in every direction including backwards and could not access the right element. What do you mean by “rock the console”?
Originally Posted by BBay
I know that there has been a lot of discussion, frustration, and complaints about the sound system in the R231 SL. On another group, I posted detailed instructions with photos on how to activate the speaker fader control. This will allow you to control the volume of the back speakers without adding any amplifier or changing any wiring. I did this on my SL 550 about eight months ago and it works very well. These instructions only work on MY 2013-2016 pre-facelift R231 SLs with Harman Kardon Logic 7 sound without Apple Car Play.
How Activate the Rear Speaker Volume/Fader Control on the R231 SL with Logic 7 Sound Comand NTG 4.5
Note…This only works on MY 2013-2016 R-231 Pre-facelift SL without Apple Car Play.
1. Enter Engineering Mode...This is performed with the engine off, ignition on, and on the Comand/Audio system number pad under the video screen. Push and Hold the Red Phone hang up button, the number 1 button, and the # symbol button at the same time. Hold all 3 buttons at the same time for approx. 5-10 seconds or until the engineering menu is displayed on the screen.
2. Using the Console Control, scroll down to number 7 (“HW Setting”) Press the console control to select.
3. Using the Console Control, scroll down to 7.7(“HU Parameter”) Press the console Control to select.
4. Rock the Console Control back to scroll all the way down to number 49 (“ Speaker Control”) Note…Rotating the console control will not allow you to scroll through the numbers to this point, rocking the control back will scroll to the proper point. Press the Console Control to select (“Speaker Control”) Scroll down to highlight (“Balance and Fader”) and press the Console Control to select.
5. On the Console Pad press the back button until you return to the (“HU Parameter”) screen and then scroll down to (“End”) and press the Console Control to select to exit the (“Engineering Menu”). The Comand system should reboot at this point. If the system does not reboot, without turning off the ignition, turn the Comand/Audio system off and back on from the button in the center of the volume control under the display screen to register and save the new selection.
Now back on the home screen, scroll to highlight (“Sound”).Along with Treble and Bass, the Balance and Fader control should be on the screen which will allow you to fade more volume to the rear and control the volume of front and back speakers as well as balance from the console control.
The Fader Control now should allow you to control the volume of the front and back speakers. This function works with Logic 7 Surround on or off. The fader settings that you set will be remembered until you change them. Each time that you turn Logic 7 surround on or off though, the speaker fader will need to be readjusted to your preference as it will return to the middle factory set point. I find that for my preference the system seems to sound much better with Logic 7 Surround on and the fader set to (-5) for the front speakers. At least now you can control the volume of all of the speakers.
I would also like to add that I would not recommend changing any of the other settings in the Engineering Menu and there are a lot of them. I am surprised though that Mercedes decided to not have the Fader control active from the factory.
Hi, trying to do this in my mom’s 2016. I got as far as “rock the console back” and tried pushing the console control in every direction including backwards and could not access the right element. What do you mean by “rock the console”?
Due to the fact that this multimedia system does not have a touch screen, control and selection is made with the console control.The round control knob on the console that is used to navigate through and select the system settings on the media screen is what I am referring to. Rotate it clockwise or counter clockwise to move the cursor/selection on the screen, push the knob to select, grab the knob and pull it back, (rock it) or push it forward to navigate the cursor/selection on the screen up or down. Push the back button to the left of the control knob to go back to the prior selection. Follow the instructions and you can't go wrong. Remember, the Fader is only accessible for activation on early MY 2013-2016 SL's Prior to the facelift/body change in 2016 when the Multimedia system was updated. If it is available for activation, it will show on number 49 under 7.7 HU Parameter. The updated version of the Mercedes Comand system that includes Apple Car Play I understand has the Fader Activation operation removed from the Engineering Mode and is not available for activation unless a Mercedes dealer is able to do so with a scan tool. I hope this helps and good luck.
Worked fine on my HK, I'm assuming you only have "balance" in the sound settings on your B & O is that correct?
Follow the instructions above and see if "balance and fade" option is listed, then it's your choice if you wish to try and activate it.
Due to the fact that this multimedia system does not have a touch screen, control and selection is made with the console control.The round control knob on the console that is used to navigate through and select the system settings on the media screen is what I am referring to. Rotate it clockwise or counter clockwise to move the cursor/selection on the screen, push the knob to select, grab the knob and pull it back, (rock it) or push it forward to navigate the cursor/selection on the screen up or down. Push the back button to the left of the control knob to go back to the prior selection. Follow the instructions and you can't go wrong. Remember, the Fader is only accessible for activation on early MY 2013-2016 SL's Prior to the facelift/body change in 2016 when the Multimedia system was updated. If it is available for activation, it will show on number 49 under 7.7 HU Parameter. The updated version of the Mercedes Comand system that includes Apple Car Play I understand has the Fader Activation operation removed from the Engineering Mode and is not available for activation unless a Mercedes dealer is able to do so with a scan tool. I hope this helps and good luck.
Okay thanks, I thought that was what you meant, I'm not sure what I was doing wrong. Her SL is a 2016 so it should work, but I couldn't get anything to happen by pushing the rocker backwards. I'll try again this week. Believe me, I wish this worked in facelift vehicles. It would have saved me a ton of money on installing that amp in my 2017 SL. But I can't stand the way music sounds in her car, so I'm determined to get this to work in her SL. Thanks for the writeup and I'll give it another go.
Did this today on my 2013 SL550. Definitely notice the change. Still waiting to have my amp installed but this will tied me over until it's done....thanks.
I just want to thank you for the writeup. I was finally able to do this in my mom's 2016 SL (finally figured out how to rock the controller back) and it made a huge difference. I'm so glad, as I had to pay to install the amp in my 2017 SL to get the rear speakers operational. I'm glad we were able to save her a ton of money with this work around, and also be able to make me stomach being in her car - her stereo used to drive me nuts, especially after I paid to have the amp put in mine. Thanks again!
I just want to thank you for the writeup. I was finally able to do this in my mom's 2016 SL (finally figured out how to rock the controller back) and it made a huge difference. I'm so glad, as I had to pay to install the amp in my 2017 SL to get the rear speakers operational. I'm glad we were able to save her a ton of money with this work around, and also be able to make me stomach being in her car - her stereo used to drive me nuts, especially after I paid to have the amp put in mine. Thanks again!
You are welcome and I am glad that you were successful with the activation.
Anyone have an idea what the reason is that this isn't active from the factory?
My car had “Speaker Control” as #47 instead of #49.
My car also didn't have Comand reboot, and when I turned the power off and then back on, the functionality wasn't active. It was only when I turned the ignition off and then back on that it became active.
Last edited by billvp218; Sep 16, 2021 at 02:38 AM.
Anyone have an idea what the reason is that this isn't active from the factory?
My car had “Speaker Control” as #47 instead of #49.
My car also didn't have Comand reboot, and when I turned the power off and then back on, the functionality wasn't active. It was only when I turned the ignition off and then back on that it became active.
I had the same experience, but all is well in the end.
I had the same experience, but all is well in the end.
I think that whether the speaker control shows at number 47 or 49 in the menu depends on the NTG Comand series software that is programmed in the media system of your vehicle. As I mentioned, I don't know why the fader function is not active from the factory to allow an improved control of the sound system.
'13 SL550 Mars Red, Designo White interior, B and O sound
B & O
Originally Posted by David2244
Worked fine on my HK, I'm assuming you only have "balance" in the sound settings on your B & O is that correct?
Follow the instructions above and see if "balance and fade" option is listed, then it's your choice if you wish to try and activate it.
Sure enough the option is presented in the engineering menu but it doesn't "take". Made no difference. I also tried turning off the ignition and then back on: no indication that the system rebooted...
in both my 2015 SL400 and 2014 C350 and the sound is amazing! Best $300 I ever spent on a car stereo. Ain't nuthin wrong with the speakers. The device has a built-in equalizer that totally changes the sound in the car. And with activating the Balance and Fader controls, I can now hear the rear speakers. I'm now convinced the stock sound on the SL is crap. I sometimes think manufacturers "detune" some models so people will be compelled to upgrade or buy options.
Last edited by JettaRed; Apr 17, 2022 at 01:52 PM.
2015 SL400 (M276 Turbo), 2014 C350 Sport (M276 NA), 2004 SL500 (M113), 2004 Audi TT225 (BEA)
Originally Posted by J1hall2
Greetings…I tried numerous times with no success. Also tried the variants described herein i.e. turning off ignition first, etc.
Not sure, but you may also want to turn off the ignition and open the driver's door to actually shut down any accessories (or have the door open when you turn off the car).
Are you certain that you have NGT4.5 or NGT4.7? I don't know when NGT5.0 was released.
FWIW, I recently installed the Road Top Wireless CarPlay Kit in both my 2015 SL400 and 2014 C350 and the sound is amazing! Best $300 I ever spent on a car stereo. Ain't nuthin wrong with the speakers. The device has a built-in equalizer that totally changes the sound in the car. And with activating the Balance and Fader controls, I can now hear the rear speakers. I'm not convinced the stock sound on the SL is crap. I sometimes think manufacturers "detune" some models so people will be compelled to upgrade or buy options.
Really happy that you like the CarPlay integration! Complete game changer with wireless CarPlay and now you have 3 truly up-to-date navigation options besides the MB Nav as well.
FYI. NTG5 was introduced on the SL with the facelift in 2016 (MY17)
2012 E Class 350 Sport Coupe, 2017 SL 450 Roadster
2017 SL450 Engineering Mode
Originally Posted by BBay
I know that there has been a lot of discussion, frustration, and complaints about the sound system in the R231 SL. On another group, I posted detailed instructions with photos on how to activate the speaker fader control. This will allow you to control the volume of the back speakers without adding any amplifier or changing any wiring. I did this on my SL 550 about eight months ago and it works very well. These instructions only work on MY 2013-2016 pre-facelift R231 SLs with Harman Kardon Logic 7 sound without Apple Car Play.
How Activate the Rear Speaker Volume/Fader Control on the R231 SL with Logic 7 Sound Comand NTG 4.5
Note…This only works on MY 2013-2016 R-231 Pre-facelift SL without Apple Car Play.
1. Enter Engineering Mode...This is performed with the engine off, ignition on, and on the Comand/Audio system number pad under the video screen. Push and Hold the Red Phone hang up button, the number 1 button, and the # symbol button at the same time. Hold all 3 buttons at the same time for approx. 5-10 seconds or until the engineering menu is displayed on the screen.
2. Using the Console Control, scroll down to number 7 (“HW Setting”) Press the console control to select.
3. Using the Console Control, scroll down to 7.7(“HU Parameter”) Press the console Control to select.
4. Rock the Console Control back to scroll all the way down to number 49 (“ Speaker Control”) Note…Rotating the console control will not allow you to scroll through the numbers to this point, rocking the control back will scroll to the proper point. Press the Console Control to select (“Speaker Control”) Scroll down to highlight (“Balance and Fader”) and press the Console Control to select.
5. On the Console Pad press the back button until you return to the (“HU Parameter”) screen and then scroll down to (“End”) and press the Console Control to select to exit the (“Engineering Menu”). The Comand system should reboot at this point. If the system does not reboot, without turning off the ignition, turn the Comand/Audio system off and back on from the button in the center of the volume control under the display screen to register and save the new selection.
Now back on the home screen, scroll to highlight (“Sound”).Along with Treble and Bass, the Balance and Fader control should be on the screen which will allow you to fade more volume to the rear and control the volume of front and back speakers as well as balance from the console control.
The Fader Control now should allow you to control the volume of the front and back speakers. This function works with Logic 7 Surround on or off. The fader settings that you set will be remembered until you change them. Each time that you turn Logic 7 surround on or off though, the speaker fader will need to be readjusted to your preference as it will return to the middle factory set point. I find that for my preference the system seems to sound much better with Logic 7 Surround on and the fader set to (-5) for the front speakers. At least now you can control the volume of all of the speakers.
I would also like to add that I would not recommend changing any of the other settings in the Engineering Menu and there are a lot of them. I am surprised though that Mercedes decided to not have the Fader control active from the factory.
Does anyone know how to get to enginerring mode to change the speaker balance on a 2017 SL450?
Thank youin advance.
I hope that this helps and Happy Motoring.
Hello, Does anyone know how to go into enineering mode to open the speaker balance on a 2017 SL450?
Just did this on my 2014 SL550. I tried it multiple times yesterday and it didn't take. This morning, I gave it one more shot, and it worked. Guess it needed to sleep on it before deciding it would accept the reprograming! 😄. Really helps to balance out the sound. Thanks for posting this fix for the radio fader control BBay!
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2017 SL450 Engineering Mode
