New RV owner with legacy EFIS - faulty ARINC interface?

[MacCool]

I recently purchased a nice RV-9A with an AFS 4500s, 3500, and a Garmin 430W. Also a TruTrak and recently installed EchoUAT. I’m sure avionics upgrades are in my future, but for the time being I’d like to learn to fly the plane. It’s currently in avionics limbo as my CFI/avionics wrangler is trying to sort out interface issues. Main problem is that the 430W doesn’t appear to be getting GPS data to the EFIS (GPS INT). The individual components all appear to be functional but they’re not working well together. With the aid of Rob Hickman (amazing customer support), and some folks at uAVionix, he’s assured that the software configurations are appropriate. He spent several hours under the panel yesterday and found that all the pins, connectors, and wires are OK. The serial port allotment is appropriate. At this point, his tentative conclusion is that the ARINC interface box is bad.

Any other suggestions? If the ARINC interface module is shot, are they available for these legacy systems? Will the ARINC 429 interface box work with the AFS 4500/3500 EFIS?

Thanks for any help. I’ve been a pilot for several decades but this is my first foray into glass and I know nothing. My buddy is quite knowledgeable, however, and has been able to keep the thing out of the avionics shop, which is good, but I would like to actually start flying this plane. I appreciate any help any of you might have. Thanks.