Around 4 am on Wednesday, i woke up because i heard the transfer switch and surge guard relay trip, then the following noise from the inverter, then the power tripped back on, then right back off. then silence and i fell back to sleep I woke up a few hrs later to the odd noise from the heater as in its was not running normal speed. like a deer in traffic i quickly checked the surge guard panel and it was dark, the 12v panel was down to 9 volts and flickering. i tried the genny and she started but no engagement of electrical load. so i shut it off and checked the power panel in the rv port to see if the 50's had tripped, by now i am dressed no tripped breakers. now I am concerned...and click the surge guard came back on and clearly shows we have power available for use........... but still no secondary click of the transfers switch. now i have donned a thick coat, crunched throw the snow and open up the power cord panel...it stunk so i quickly killed power and then opened up the transfer switch.. yep it was burned up and caused my pucker factor to increase. ordered a new upgraded surge guard transfer switch, which arrived this morning..thank goodness for over night AIR freight. I had bypassed the transfer switch and was able to get power to the coach, and now the rebuild continues tomorrow i am replacing the entire main coach line to the circuit breaker box, to be safe, something caused 6 or so inches of insulation on the white return line to melt..... so please check your transfer switch for corrosion, as i suspect this is what caused the failure. plus the factory installed switch had 10 gauge wires inside vice the 6 on the surgeguard so it was nominal at best more pics tomorrow when i am all done what gets me is, I am anal retentive at checking wiring lugs for tq and corrosion.