I managed to add the BRM clock and also change my start/stop button very easily.
You just need the following parts:
I’ve created a PDF guide which can be viewed here:
Replacing start stop button or BRM clock in a DS 7 CROSSBACK-min.pdf (4.0 MB)
Really nice upgrade 
Yes it really is. It finishes the interior off nicely. Curious to know why there is an option in the BSI to enable/disable the clock though. It seemed that the clock works even if it’s disabled in the BSI. 
Hi!Newbie in the forum here…Owner of DS7 Crossback 1.5 hdi Performance Line since 27/01/2021.In love with my goddess…Thank you very much for the above tip.I am interested to replace the 8 inch multimedia Center with the 12inchess.Is this possible?In Greek DS service station they told that it is impossible.
Wishing all the best to this forum!
Greetings from Greece
Stefanos
Yes it should be possible. Have you removed the 8” screen at all to look at the connections? It may just simply require you to change the part, and reconfigure BSI and some ECUs.
Worst case scenario you might have to alter the wiring loom.
Are there any Peugeot specialists in Greece? It may be worth contacting them.
@Dave any tips? 
Good morning Alex,
Thanks for your quick response.
They told me that it is impossible because of the ECU.
I strongly believe that they want to avoid this modification while the car is within guarantee.
I think that after first released cars 5 years guarantee expiration we will see many options for upgrades.
Best
Stefanos
It’s not impossible, but your dealer won’t be able to do it. You have to find someone like a Peugeot specialist
Hi Stefanos
Yes it is possible to replace the 8" for the 12".
You will require a replacement main control unit called (NAC wave 3 HD) and a 12" touchscreen.
There are 2 types of NAC wave 3 (SD) which you likely already have if if your car has GPS, these support 8inch and 7inch touchscreens.
NAC wave 3 (HD) support widescreen 10" and 12" touchscreens.
Cables are the same unless you don’t already have GPS you will need gps antenna. The NAC will also need configuring to your VIN.
Thanks Dave!
Appreciate your assistance.
My car does not have any GPS installed and being able to use a GPS via Apple Car Play.
If I replace the 8” with 12” and NAC 3 HD,shall I have the ability to view the GPS screen over the Digital Instrument Panel in front of the wheel as well?
Any estimated cost for all this job including 12” screen?
If any Peugeot specialist from Greece sees this post, please let me know…
Appreciate your assistance!
Yes if you replace the 8” with 12” plus NAC 3 HD you will have the ability to view the GPS screen over the Digital Instrument Panel in front of the steering wheel.
You will require additional LVDS cable to connect NAC wave 3 to Digital Instrument Panel
Estimated cost of project;
Nac wave 3 HD version = £200
LVDS cable = £30
12" screen = £200
Additional configuration required to activate the GPS function on Digital Instrument Cluster and programming of the NAC Wave 3 to your cars VIN and specifications.
Happy to help
Dear Dave,
Appreciate your feedback.
If you know someone in Greece who could assist to perform this modification it would be fine.
Thanks!
Stefanos
Hi Stefanos if you are confident in fitting the parts yourself I would recommend locating a scrapped DS7 and buying the parts you need from the same car. I can help you with coding the parts remotely if you buy a DIAGBOX / lexia tool.
Is there anywhere else that you can buy a brm clock other than a main dealership
Yes, bartebben is a good site to use. Is your car left or right hand drive? I can send you some links.
Hello, is the harness already in place to connect the clock?
hello I would like to ask you but how did you mount the clock if the BRM one has two connectors behind it ??
Because I want to upgrade mine too
Thanks for the help
Hi Dave, you sound to me you got some experience on this matter. Could you advice if we can swap the NAC wave 2 for the new DS IRIS?
We got the DS9 2022 and DS7 from 2018. Would love to be able to upgrade it to the new system and have some indication of the costs.
Is there a way to stop the BRM clock opening and closing mechanism? In my 2019 Prestige, the BRM clock can’t close properly, it closes halfway down before the mechanism makes a crunching noise and then returns back up. I would prefer it if it didn’t move at all than this.
Hi Steve,
Yes, if you follow the instructions in reverse on this thread, to remove it, then you can open up the side of the clock (a few screws) and disconnect the motor. Leave the other electronics connected, just disconnect the revolving motor.
I did it with mine, I bought a la premiere clock (it’s red, not black) but the thing didn’t open properly, same issue as yours.
Thanks,
Alex
