Just returned from a trip, plugged the trailer back into AC and the fridge control box is dead completely, not just an issue with the gas not firing. On/off switch does nothing. Tried holding various buttons down to see if there was a reset or something, nada.

Checked panel breaker and 12v, both are fine. Checked AC and DC to rear panel behind the cover, both are nominal going into the board. Checked both obvious exposed fuses, there's a 5amp glass fuse on the panel and a 3amp inside a 12v wire and both were fine.

Anything else I can easily check (and fix if its dead) before I make an appointment with the dealer?