Does anyone know if the DJI Compass / GPS for the A3 will work with an A2? Assuming the technology is compatible, I can see that the A3's Compass / GPS Pro has a different CAN-bus connector - is that compatible with the A2 flight controller's "special" CAN-bus connectors or the 1 "special" CAN-bus connector on the CAN-hub?
  
Actually, I have a 2nd question: Is there a different between a "Compass / GPS Pro" and a "Compass / GPS Pro Plus"?
The manual for the A2 lists a "Compass / GPS Pro Plus" as "In the Box" (Page 4) with a picture of the top of a Compass / GPS dome with the full text "Compass / GPS Pro Plus". But, my Compass / GPS is the same shape and (seems) to be the same size, but the text on mine says "Compass / GPS Pro"

The problem is that my A2 Compass / GPS Pro (Plus?) unit seems to have a dead CAN-bus connector.
I don't think it is completely dead - it shows up in the A2 Assistant and it will complete a compass calibration.
I'm using an iOSD Mark 2, but there is no A2 flight data displayed on the monitor (just the iOSD labels where the data should be).
I tried using a CAN-bus hub, but that didn't work.
There are several DJI Compass / GPS units on eBay with the label "A3" on the "dome", but none that specifically show A2 compatibility (I am only looking at the A3 Compass / GPS. Not the upgrade kits)
This is a "new to me" drone and flight controller.
I am 6 or 7 years behind the learning curve for this flight controller, and I've never had it flying.
It is all used equipment, so it's possible there are a lot of problems.

The general answer I'm seeing on other forums is "No. The DJI GPS-Compass from an A3 will not work with the A2.
So, the next questions are:
Do I really need a DJI GPS-Compass Pro Plus with the A2?
Or is the DJI GPS-Compass Pro good enough?

Since this sytem is used, but new-to-me, I have no idea why or how this A2 got a DJI GPS-Compass Pro on it instead of a DJI GPS-Compass Pro Plus.