$676 is the VO code for the HIFI unit with 12 speakers but you should read your FA listing all your VO codes and you should see $676 already there, and no other coding should be required.....
BUT yoru error message shows you're not getting response from your CAS module so there maybe something else going on and I assume you have not seen your VO listing

Edit
Have you managed to read any faults at all?

 

Ok, so got this figured out and have successfully changed coding using ncsdummy (awesome sticky guide that was made by revtor btw), amending MASK profile ad using the nettoman.dat trace method to recode with ncsexpert 😊

Fair few options to play with, but to resolve my two issues…changed system output to HIFI and also changed the warning/parking sensor levels to MIN3. Deffo resolved the problem

I may reduce the warning/parking sensor levels to MIN1 and then I get set my gains higher on amp for audio to balance it acceptable levels (before any + on gains resulted in the warning level increasing too to deafening levels like)

Is anyone familiar on what the output spec of TOPHIFI is compared to HIFI? Also there is one called FLAT…again any detail on this?

( no idea what the error was that i screen shotted eralier, but $676 has been added sucessfully from earlier attempt )