My 2012 RNS850 died last week, screen went black, no sound or life. I asked an auto electrician to have a look, CD/radio tuner was still live and head unit was still live. He ran out of time to test the rest so I ordered an optical fibre loop to confirm or eliminate the amp. The unit is still dead with the loop fitted so next test is the optical fibre. I plan to somehow connect the CD/radio tuner to the amp with a new optical fibre to see if that is the issue. Fingers crossed !
This video really helped me start diagnosing the problem with my rns850! The screen will sometimes not come on when we fire up the car and may take up to an hour to do so unless I perform a soft reset which makes it work instantly. So we opened up the fuse box as you did to check each fuse and when we checked fuse 51 (20amps), it seemed ok but when we pulled it out and put it back, the screen came to life! The funny thing is that when the screen does come on in any instance, it never goes off unless we switch the car off for over 20 minutes (i.e. when the car shuts down electricals completely). What do you think the issue could be?
@mas audio please could you help us with this issue we are having? We have followed your video and its worked. I have found a used radio unit on ebay, can I just buy this? Or would you be able to help on how to repair our old one? Your video has been such a help! Thank you
Nice work! My RNS850 does not fire up at all. I have checked fuses, and scanned with VCDS and get the following errors; Address 19: CAN Gateway (J533) 1 Fault Found: 0269 - Optical data bus U104A 00 [009] - No Communication Confirmed - Tested Since Memory Clear Freeze Frame: Fault Status: 00000001 Fault Priority: 6 Fault Frequency: 7 Reset counter: 218 Mileage: 68230 km Address 56: Radio Cannot be reached Address 5F: Information Electr. Cannot be reached The unit in the glove box seems to still work / make noises if i press eject. I have also tried to run VCDS "Optical Bus Diagnostics" but both "standard" and 3db modes just give me a error "Refused by Control Module" i'm not sure if the RNS850 uses a CAN gateway 7P6907540A or is it the Display screen or i don't know what control module it means.... Any ideas would be greatly appreciated, Cheers.
@@MASAudio I bought another RNS850 and it works! I wonder if there is a another fuse within my original MMI that has blown. Although the CD drive part of it was still alive they may have seperate fuses, or the PSU died for the MMI side? I wonder if its a easy fix... Either repair the old one or get component protection removed from this one..
@@fatsubsonic They dont normally have separate internal fuses, although there could be some CP links etc in the circuit. The component protection can be removed but only if you have the data from the donor vehicle. or at the very least, the VIN of the donor vehicle and a dealer with ODIS willing to do it. We have had one unit in an audi coded, but because the model and year differed slightly, it only worked as MMI Audio, no car info or dash settings worked.
@@MASAudio Thanks for reply. My original RNS850 is revision "B" and the replacement is revision "D" (manufacture date is about 12months newer) I have been able to customise the options to suit the specs of my Touareg. Removing options like ACC and Lane assist, and adding option for Off-Road nav waypoints as i have the 4Xmotion. So everything works now except media audio. (Even bluetooth phone call audio works too) I assume component protection should resolve the lack of Media audio/video. Fingers crossed. I have the VIN of the original vehicle so i hope there shouldn't be any issues. *fingers crossed*
So my 2012 tdi screen powers on and displays welcome to vw, then it goes blank. According to vw they said it was the 5f module. I swapped it out and it still won't communicate. I noticed there was no fuse in 51 and when I went to plug one in it immediately popped the fuse. Is that similar to the issue that you were having?
@@MASAudio do have the a part number for the fiber optic cable? I have replaced everything and it will not stay on. I want to replace the amp but want to test it first. One mechanic told me they did it and it didn't stay on so I replaced the head unit.
@@brucedrummond2331 you dont want to listen to mechanics, also replacing parts with used or new? Used wont work as they are coded to the car, you need ODIS to program the modules or it will ignore foreign modules making it impossible to diagnose.
@@MASAudio used but they have all been tested. I love the diesel sounds but need to get to some parameters. I know I have to get it programmed but I need it to stay on first lol
How you don’t have 100k likes on this is shocking. This is exactly what has/is happening to about 100k of these.
This video has reallt helped! Thank you so much for making the video. Did you manage to fix the amp or did you need to replace with a new one?
Can you post the video of you replacing the amp?
My 2012 RNS850 died last week, screen went black, no sound or life. I asked an auto electrician to have a look, CD/radio tuner was still live and head unit was still live. He ran out of time to test the rest so I ordered an optical fibre loop to confirm or eliminate the amp. The unit is still dead with the loop fitted so next test is the optical fibre. I plan to somehow connect the CD/radio tuner to the amp with a new optical fibre to see if that is the issue. Fingers crossed !
This video really helped me start diagnosing the problem with my rns850! The screen will sometimes not come on when we fire up the car and may take up to an hour to do so unless I perform a soft reset which makes it work instantly. So we opened up the fuse box as you did to check each fuse and when we checked fuse 51 (20amps), it seemed ok but when we pulled it out and put it back, the screen came to life! The funny thing is that when the screen does come on in any instance, it never goes off unless we switch the car off for over 20 minutes (i.e. when the car shuts down electricals completely). What do you think the issue could be?
I have the same problem what was ur fix?
@mas audio please could you help us with this issue we are having? We have followed your video and its worked. I have found a used radio unit on ebay, can I just buy this? Or would you be able to help on how to repair our old one? Your video has been such a help! Thank you
Do you have the video to take the trim off in the boot ?
Nice work!
My RNS850 does not fire up at all. I have checked fuses, and scanned with VCDS and get the following errors;
Address 19: CAN Gateway (J533)
1 Fault Found:
0269 - Optical data bus
U104A 00 [009] - No Communication
Confirmed - Tested Since Memory Clear
Freeze Frame:
Fault Status: 00000001
Fault Priority: 6
Fault Frequency: 7
Reset counter: 218
Mileage: 68230 km
Address 56: Radio
Cannot be reached
Address 5F: Information Electr.
Cannot be reached
The unit in the glove box seems to still work / make noises if i press eject.
I have also tried to run VCDS "Optical Bus Diagnostics"
but both "standard" and 3db modes just give me a error "Refused by Control Module"
i'm not sure if the RNS850 uses a CAN gateway 7P6907540A or is it the Display screen or i don't know what control module it means....
Any ideas would be greatly appreciated, Cheers.
I would link out the suspect units with a fibre optic loop, and see if the system comes back on.
@@MASAudio I bought another RNS850 and it works! I wonder if there is a another fuse within my original MMI that has blown. Although the CD drive part of it was still alive they may have seperate fuses, or the PSU died for the MMI side?
I wonder if its a easy fix...
Either repair the old one or get component protection removed from this one..
@@fatsubsonic They dont normally have separate internal fuses, although there could be some CP links etc in the circuit. The component protection can be removed but only if you have the data from the donor vehicle. or at the very least, the VIN of the donor vehicle and a dealer with ODIS willing to do it. We have had one unit in an audi coded, but because the model and year differed slightly, it only worked as MMI Audio, no car info or dash settings worked.
@@MASAudio Thanks for reply. My original RNS850 is revision "B" and the replacement is revision "D" (manufacture date is about 12months newer) I have been able to customise the options to suit the specs of my Touareg. Removing options like ACC and Lane assist, and adding option for Off-Road nav waypoints as i have the 4Xmotion. So everything works now except media audio. (Even bluetooth phone call audio works too) I assume component protection should resolve the lack of Media audio/video. Fingers crossed. I have the VIN of the original vehicle so i hope there shouldn't be any issues. *fingers crossed*
So my 2012 tdi screen powers on and displays welcome to vw, then it goes blank. According to vw they said it was the 5f module. I swapped it out and it still won't communicate. I noticed there was no fuse in 51 and when I went to plug one in it immediately popped the fuse. Is that similar to the issue that you were having?
Did you replace the amplifier to correct the issue?
No I repaired the amplifier and yes the fuse was blowing due to a bad amplifier.
@@MASAudio do have the a part number for the fiber optic cable? I have replaced everything and it will not stay on. I want to replace the amp but want to test it first. One mechanic told me they did it and it didn't stay on so I replaced the head unit.
@@brucedrummond2331 you dont want to listen to mechanics, also replacing parts with used or new? Used wont work as they are coded to the car, you need ODIS to program the modules or it will ignore foreign modules making it impossible to diagnose.
@@MASAudio used but they have all been tested. I love the diesel sounds but need to get to some parameters. I know I have to get it programmed but I need it to stay on first lol