Looking good so far!
I'm glad you solved the problem with the aux input -- I was worried that I had connected a wire wrong.
I'm surprised that your WRX's mic works. I need to check more thoroughly, but I had found that a WRX with the FT nav has a different part number for the map light cluster than a WRX with the CZ624U1 (non-nav HU). The only difference would be the mic module. Both nav and non-nav mics are amplified. I figured the two used different gains.
I contacted a BRZ owner who is the parts manager for a Subaru dealership. He found the USB cable for the BRZ (86273CA000, MSRP $121
). I didn't realize that it is wrapped together with a portion of the aux harness. The online price is about $89 plus shipping, which is still too much when all you want it for is the USB plug.
I've asked him to check the similar USB harness in Impreza/WRX/STI with the FT nav. I know the harness is a separate piece in those cars, so I'm hoping it will be slightly cheaper.
As for finding the FT USB plug as a separate piece, I don't know the manufacturer or model number for that. I'll need a Subaru or Toyota owner who has a HU with this socket to look closely at the plug on their car's USB harness. There should be a manufacturer's name or logo on it. That's how I figured out that Hirose makes the USB connectors for the non-nav cars (in the picture here
, I saw the "HRS" on the plug and knew it was Hirose).
I'm fairly sure that Hirose is not
the manufacturer for the Toyota USB connector -- I didn't spot anything like it in their catalog. There are many other companies.
Be very careful before you try to shove something into the FT nav's USB socket. If you damage it and then we do find the proper plug, you won't be able to use it. Trust me, you really don't
want to solder to the HU's PC board.
I'll let you know what the parts guy says about the Impreza USB cable.