Remote control unit not found

"RCU not found" is the message I get when I try to configure the RMK9 on my GS165 yet in diagnostics it finds it with serial number on SeaTalk HS. Per the install manual I did not connect the separate red power wire since the remote will get power via Seatalk.

If it's relevant, I also got a message stating:
The following devices are preventing data source selection. E22158 SeaTalk STNG-Converter S/N 0240860

Thanks.