Guide for anyone trying to install an aftermarket radio in a Benz with Harman Kardon Audio. I did this in my w211 e class. It should apply to other cars in similar generations (w203, w220, etc...)
Product: Android 10 9-inch GPS Car Radio Stereo Multimedia for Mercedes-Benz E-Class W211 | eBay - not the exact radio I bought but same size.
Some things to consider before you begin -
1. If you have a CD changer installed in the car, the 9 inch radios will make your life difficult with the install, and you will not be able to use said CD Changer anymore.
2. MOST fiber optic box is necessary, add in $110 to whatever price you are planning on paying for a radio.
Now, when purchasing a MOST box, I had better luck with one of the boxes that came with a red ACC wire in addition to the B+ yellow and GND black wire. Others have made the 2 wire ones work, but I have had 0 issues with the 3 wire ones. From what I can tell, these boxes are hit or miss, absolutely spend an extra $20 or so for a reputable brand such as XTRONS.
STEP 1. Remove shifter cover by lifting up on it, and do the same for cigarette lighter compartment. There are no screws holding these in but you will have to unclip a few wiring harnesses. Cig lighter wiring harness may give some problems, the connector pulls off upwards instead of backwards. You will figure it out.
STEP 2. remove 2 screws holding in CD changer and disconnect 3 cables (right most cable is for the CD changer, middle is the fiber optic connection, and left most 6? pin connector is for the ESP, lock/unlock and other buttons on that panel.) The screws should be t25? Maybe T20. Do not totally remember, a Torx screwdriver set helps.
STEP3. Remove CD changer. This is when the fun begins... If your new radio bracket is anything like mine, it will not just fit over the CD changer, some of the trim gets in the way. My solution was to disassemble the entire CD changer and remove it all together.
If you decide to do what I did and delete the entire CD changer, you will have to plug all plugs back in, and open the CD changer, then unplug. With CD changer open, you can access 2 t15/10? screws on the sides. At this point take the whole CD changer assembly off the car and work on it with more space. undo the 2 t15 screws, and go to the bottom/back of the changer assembly. There is a wire cover panel all across the back of the assembly. This should come off fairly easy, just a few plastic tabs. With that dangling from the assembly, fiddle with the Fiber optic connection, and the CD power connection to release them from the assembly harness, they should be held in by plastic clips. With the CD changer open, the screws removed, and both plastic wire clips loose (red, yellow, black wires, and the 2 black or orange Fiber wires), you can simply slide the CD changer out of the assembly.
Now, looking from the back of the CD changer, there will be 4? T8 screws holding the button panel and the trim panel on to the assembly. Remove these to free the button panel with lock/unlock. If your radio does not interfere or overlap with the CD changer assembly, you are lucky, you can just remove the wood trim and put it all back together. If they overlap you will have to do some more fun stuff. You can shave down the CD changer assembly to allow the radio bracket room to fit over it, or you can just delete the entire CD changer assembly like me. To do this, you have to remove the 6 pin connector from its bracket. Then you can remove the motor assembly by removing the 2 t15 or t20 screws. There are 2 separate wiring harnesses that run the length of the CD changer assembly. When looking from inside the car, the left side is the only side that matters (side without the green cover). It brings data regarding the hazards, door locks etc. You may have to cut these 4 wires in order to string them through and resplice them so you just have the 4 wires connector for the left side of the button control panel. The 6 pin connector and the left side 4 wire connector is all you need from the CD changer if you are deleting the CD changer.
BEFORE STEP 3.
Either disconnect battery at this point, or remove the fuse 24 and 26 from the left side fuse box right near the driver side door. These fuses should be 5 amp and 7.5 amp. One is for CD changer, other is for radio. To be extra safe, either disconnect battery, or pull fuse 8 from the trunk driver side fuse box (40 amp, goes to amp).
STEP 3. Removing the radio is easy. 2 T15 screws that you unscrew all the way from underneath, they will stay in the car and not fall out. Slide the radio out and disconnect the 1 wiring connector from the back of the radio. If your radio has a second 3 pin connector on the passenger side, this is for the aux cord. Disconnect it and do not worry about it anymore. separate the 3 pin connector and the fiber optic lines from their harness on the radio. If you are comfortable, feel free to cut off the 3 pin connector that powers the radio. Pink is trigger wire (ignore), Brown is ground, Red+yellow is BAT+.
STEP 4. Wiring - outside the car, connect your MOST box red ACC wire to your new headunit red ACC wire, and do the same with yellow BAT+ and Brown GND. Back to the car. either cut or strip your cig lighter power cable (red) and splice both red ACC wires into this wire. Then, splice both yellow BAT+ wires into the red/yellow wire from the radio 3 pin connector, and finally, splice both GND wires into the brown ground wire from the old radio connector. Now, insert the fiber optic line from the radio into your MOST box (you may need to remove the 2 lines from the plastic connector). You will also need a fiber optic loop ($8 on amazon) that clips in where the CD changer used to be. Once all of these lines are connected, make sure all wires are secure and covered, feel free to turn on your car and verify that the radio screen powers on. With the car back off, find the Lamp/Illumination wire from your new radio. It should be orange or pink. Splice or connect this to the small blue wire that come off of the cigarette lighter harness. This will allow you to retain backlighting settings for your new radio.
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This is what worked for me. I would avoid attaching anything the to RED wire from the canbus box. Feel free to use the illumination and other wires from the canbus box if you would rather do that than splice into the cig lighter.
STEP 5. Connect accessory cables to the back of radio as you wish. Your radio should come with a connector that has RCA audio output cables labeled audio out L and audio out R. Plug these into the fiber optic decoder box in order to have sound. With all this done, you should be ready to start installing everything. Start by Screwing your radio screen into the bracket it came with, then screw the T8 screws for the lock/unlock button panel into the bottom of the frame. Connect the 6 pin connector from before to its opposite end inside of the car on the bottom left. Now plug everything into their respective spots, and tighten the 2 vertical screws underneath the radio to secure it (That part can be tricky.) If you are keeping your cigarette lighter, reattach the connector and place it back.
STEP 6. Adding Steering Wheel Controls - At this point, audio and everything should work. To get SWC, take your CANBUS decoder box and wire the yellow wire from the box to RED from the Headunit and FO box. Next, connect black wire to GND, then go underneath the glovebox and find the CAN port, plug the green connector from the box into the can port, then plug the white connector from the canbus box into the spot for it on the back of the headunit.
IMPORTANT THINGS TO REMEMBER. Do not forget to connect the 6 pin connector from the hazard/locking panel. Do not forget to attach the RCA cables, make sure all fiber optic cables are in. They have to either have a loop, or be connected to something like the decoder box.
Remember - this is an install WITHOUT the CANBUS box, so you will not have steering wheel controls. Everything else will work.
Tip - buy a Autokit carplay adapter for your android headunit if you want to use android auto or apple carplay.
I bought this one Amazon.com: AutoKit CarPlay Wireless CarPlay USB Adapter/Android Wireless USB Adaptor for Wired Android Auto,Fit for All Android 4.4 or Above Car Radio USB Connection : Electronics . Well worth it.
If you have any questions or concerns. Feel free to reach out, I had plenty of problems during my install so I've had to troubleshoot most common issues along the way.
EDIT: Added Wiring Diagram picture and pdf, added in Steering Wheel Controls.
Product: Android 10 9-inch GPS Car Radio Stereo Multimedia for Mercedes-Benz E-Class W211 | eBay - not the exact radio I bought but same size.
Some things to consider before you begin -
1. If you have a CD changer installed in the car, the 9 inch radios will make your life difficult with the install, and you will not be able to use said CD Changer anymore.
2. MOST fiber optic box is necessary, add in $110 to whatever price you are planning on paying for a radio.
Now, when purchasing a MOST box, I had better luck with one of the boxes that came with a red ACC wire in addition to the B+ yellow and GND black wire. Others have made the 2 wire ones work, but I have had 0 issues with the 3 wire ones. From what I can tell, these boxes are hit or miss, absolutely spend an extra $20 or so for a reputable brand such as XTRONS.
STEP 1. Remove shifter cover by lifting up on it, and do the same for cigarette lighter compartment. There are no screws holding these in but you will have to unclip a few wiring harnesses. Cig lighter wiring harness may give some problems, the connector pulls off upwards instead of backwards. You will figure it out.
STEP 2. remove 2 screws holding in CD changer and disconnect 3 cables (right most cable is for the CD changer, middle is the fiber optic connection, and left most 6? pin connector is for the ESP, lock/unlock and other buttons on that panel.) The screws should be t25? Maybe T20. Do not totally remember, a Torx screwdriver set helps.
STEP3. Remove CD changer. This is when the fun begins... If your new radio bracket is anything like mine, it will not just fit over the CD changer, some of the trim gets in the way. My solution was to disassemble the entire CD changer and remove it all together.
If you decide to do what I did and delete the entire CD changer, you will have to plug all plugs back in, and open the CD changer, then unplug. With CD changer open, you can access 2 t15/10? screws on the sides. At this point take the whole CD changer assembly off the car and work on it with more space. undo the 2 t15 screws, and go to the bottom/back of the changer assembly. There is a wire cover panel all across the back of the assembly. This should come off fairly easy, just a few plastic tabs. With that dangling from the assembly, fiddle with the Fiber optic connection, and the CD power connection to release them from the assembly harness, they should be held in by plastic clips. With the CD changer open, the screws removed, and both plastic wire clips loose (red, yellow, black wires, and the 2 black or orange Fiber wires), you can simply slide the CD changer out of the assembly.
Now, looking from the back of the CD changer, there will be 4? T8 screws holding the button panel and the trim panel on to the assembly. Remove these to free the button panel with lock/unlock. If your radio does not interfere or overlap with the CD changer assembly, you are lucky, you can just remove the wood trim and put it all back together. If they overlap you will have to do some more fun stuff. You can shave down the CD changer assembly to allow the radio bracket room to fit over it, or you can just delete the entire CD changer assembly like me. To do this, you have to remove the 6 pin connector from its bracket. Then you can remove the motor assembly by removing the 2 t15 or t20 screws. There are 2 separate wiring harnesses that run the length of the CD changer assembly. When looking from inside the car, the left side is the only side that matters (side without the green cover). It brings data regarding the hazards, door locks etc. You may have to cut these 4 wires in order to string them through and resplice them so you just have the 4 wires connector for the left side of the button control panel. The 6 pin connector and the left side 4 wire connector is all you need from the CD changer if you are deleting the CD changer.
BEFORE STEP 3.
Either disconnect battery at this point, or remove the fuse 24 and 26 from the left side fuse box right near the driver side door. These fuses should be 5 amp and 7.5 amp. One is for CD changer, other is for radio. To be extra safe, either disconnect battery, or pull fuse 8 from the trunk driver side fuse box (40 amp, goes to amp).
STEP 3. Removing the radio is easy. 2 T15 screws that you unscrew all the way from underneath, they will stay in the car and not fall out. Slide the radio out and disconnect the 1 wiring connector from the back of the radio. If your radio has a second 3 pin connector on the passenger side, this is for the aux cord. Disconnect it and do not worry about it anymore. separate the 3 pin connector and the fiber optic lines from their harness on the radio. If you are comfortable, feel free to cut off the 3 pin connector that powers the radio. Pink is trigger wire (ignore), Brown is ground, Red+yellow is BAT+.
STEP 4. Wiring - outside the car, connect your MOST box red ACC wire to your new headunit red ACC wire, and do the same with yellow BAT+ and Brown GND. Back to the car. either cut or strip your cig lighter power cable (red) and splice both red ACC wires into this wire. Then, splice both yellow BAT+ wires into the red/yellow wire from the radio 3 pin connector, and finally, splice both GND wires into the brown ground wire from the old radio connector. Now, insert the fiber optic line from the radio into your MOST box (you may need to remove the 2 lines from the plastic connector). You will also need a fiber optic loop ($8 on amazon) that clips in where the CD changer used to be. Once all of these lines are connected, make sure all wires are secure and covered, feel free to turn on your car and verify that the radio screen powers on. With the car back off, find the Lamp/Illumination wire from your new radio. It should be orange or pink. Splice or connect this to the small blue wire that come off of the cigarette lighter harness. This will allow you to retain backlighting settings for your new radio.
This is what worked for me. I would avoid attaching anything the to RED wire from the canbus box. Feel free to use the illumination and other wires from the canbus box if you would rather do that than splice into the cig lighter.
STEP 5. Connect accessory cables to the back of radio as you wish. Your radio should come with a connector that has RCA audio output cables labeled audio out L and audio out R. Plug these into the fiber optic decoder box in order to have sound. With all this done, you should be ready to start installing everything. Start by Screwing your radio screen into the bracket it came with, then screw the T8 screws for the lock/unlock button panel into the bottom of the frame. Connect the 6 pin connector from before to its opposite end inside of the car on the bottom left. Now plug everything into their respective spots, and tighten the 2 vertical screws underneath the radio to secure it (That part can be tricky.) If you are keeping your cigarette lighter, reattach the connector and place it back.
STEP 6. Adding Steering Wheel Controls - At this point, audio and everything should work. To get SWC, take your CANBUS decoder box and wire the yellow wire from the box to RED from the Headunit and FO box. Next, connect black wire to GND, then go underneath the glovebox and find the CAN port, plug the green connector from the box into the can port, then plug the white connector from the canbus box into the spot for it on the back of the headunit.
IMPORTANT THINGS TO REMEMBER. Do not forget to connect the 6 pin connector from the hazard/locking panel. Do not forget to attach the RCA cables, make sure all fiber optic cables are in. They have to either have a loop, or be connected to something like the decoder box.
Remember - this is an install WITHOUT the CANBUS box, so you will not have steering wheel controls. Everything else will work.
Tip - buy a Autokit carplay adapter for your android headunit if you want to use android auto or apple carplay.
I bought this one Amazon.com: AutoKit CarPlay Wireless CarPlay USB Adapter/Android Wireless USB Adaptor for Wired Android Auto,Fit for All Android 4.4 or Above Car Radio USB Connection : Electronics . Well worth it.
If you have any questions or concerns. Feel free to reach out, I had plenty of problems during my install so I've had to troubleshoot most common issues along the way.
EDIT: Added Wiring Diagram picture and pdf, added in Steering Wheel Controls.
