What’s the difference between these two PDC modules?


Registered User
I want to retrofit rear PDC to my 2013 1.4 A3. I’ve searched online for parts, and I’ve noticed two different modules that people claim are suitable for this car.

I wanted to know the difference between the two, and which one I need. These are the part numbers:


Also, what variations are there for the last letter in these part numbers? I’ve seen several vendors who sell 5Q0919294E, but I’m not sure it’s the one I need.