swsmith

Next time I fly I’ll take a picture of the breaker panel. It did have extensive rewiring when all the garmin boxes were installed.

My 1979 K doesn’t have that. The relay is also the part that failed and it didn’t failed in a way that allowed power to still flow. I’ve heard the 24v systems do this but mine is a 12v system

Thanks! Yes we didn’t have a AUX breaker. I’ve flown in later model Mooney’s with them and I’m aware of how they work. Funny enough we managed to fly to all lower 48 states on the fifty project trip only a few months before this happened with no issues so we were probably due for it.

Following up on this - we managed to fix the airplane and in doing so we added a "avionics master bypass" switch in case this ever happens again.

Thanks this is helpful. What does the circuit breaker switch look like? Did you remove the original avionics switch?

Depends on the airport. We were shooting the RNAV into KTIW, we found approach’s number but not tower’s number. Approach then contacted the tower for us.

ForeFlight

So I had a fun experience the other day. I was on a local flight shooting some instrument approaches and during an RNAV approach all my avionics suddenly switched off. Our next step was calling up ATC on the phone and declare. This was a fun experience since they couldn’t hear us at first but when they did finally hear “N231ER Declaring an emergency, complete avionics failure, IFR” you could hear the ATC controller hurriedly calling her boss. I lost com 1&2, GPS, Transponder, JPI engine monitor, intercom, and nav radios. Luckily we still had power to the lights, gear and flaps since it was at night. I’ve got a pretty well equipped panel and didn’t have a backup radio so cell phone was the only option. We got on the ground safely at the nearest airport and started to troubleshoot. We (well really the mechanic) diagnosed the issue was with the Avionics relay, it was no longer creating a circuit. We got the part number (MB4413) and have been trying to track it down. Any leads would be appreciated. I’ve called BAS, Mid-Continental and Lasar. Our best option seems to be the avionics relay upgrade kit which is currently $1800 from Lasar. Ouch Heres a pic of the panel: we lost everything to the right of the JPI.