330ES Transponder No Longer Boots up Automatically

[BLMike]

I just got my plane out of annual (and IFR equipment cert (altimeter, encoder and static system)). Previous to this, my transponder (Garmin 330ES) automatically turned on when I switched the avionics switch on. Suddenly, I have to manually turn on the transponder after the avionics switch is turned on. Any ideas as to what may have changed?

 

[GeorgeC]

Pin 1, "avionics master on select".

 

[Jesse Saint]

Pin 1 on the GTX330(ES) is the Avionics Master On pin. If you give power to that pin with the Avionics Master, it will turn the transponder on. If the transponder power is coming from the avionics bus, you can just jumper pin 1 to one of the power pins on the 330 (21 and 42 for Power 1 or 56 and 60 for Power 2).

 

[BLMike]

Thanks so much guys! That one pin, pushed back out of the connector a little which caused the problem. We re-seated the pin and the problem is solved.