Diva1969

I have a 2010 S5 coupe (manual transmission). I am having issues with the MMI randomly working. I am trying to figure out all the potential components that work wiht the MMI screen so I can determine the root cause.
Does anyone know the related components that work with the MMI system (display, module, controller, additional modules, etc.)?

SMac770

Do you have MMI 3G navigation plus?
The J794 main control unit in the dash, the E380 control head (buttons/dial) in the center console, the J685 front information display (FID, the screen).
Then there's the other optical bus members, the J533 CAN Gateway, the R radio, and, if you have B&O, the J525 sound system (amp).

Diva1969

Thanks! I'm not sure which MMI version I have (I believe it is the first 3G version). I have a CD changer, navigation (though it has never worked because I didn't sign up for service) and iPod/Aux input in the glove box (that I have an updated adapter that fits my iPhone 11 that I purchased from Audi). It has the bluetooth option but it is limited (bluetooth doesn't stream my music or apps like Waze).

I'm trying to figure out where the root cause of the issue is (and have tested with multimeter for the fuse component). I'm hoping it isn't the entire controller/module that is bad as I know it is very expensive to fix (and difficult to find parts that are less expensive than directly from Audi). I also was looking into upgrading the display to use CarPlay (but didn't know of a quality solution that really worked - Audi directly doesn't have it and has no plans to).

SMac770

"CD changer"? Is it in the glove box? Because the CD changer in the dash would be MMI 2G, but you shouldn't have that with a "2010". But Europe doesn't have clear cut model year designations like we have in the US. So "2010" is an ambiguous term somewhat.

The most useful information for "what do I have" would be a full vehicle scan log from VCDS or such. But you can determine your MMI version from the about screen just as well: youtu.be/R2mUmxFPWBQ?t=158

Audi will never have anything for CarPlay for B8 vehicles. You'll have to look at third party solutions like RSNAV.com. But they do not replace the MMI system for vehicle functions purposes.