Comfort Pro Apu Issues (solved)

I bought a used Milton truck back in Sept.. Up until recently i've only did routine maintenance which is fairly cheap seeing as how it's only every other month.. In all honesty I spent more money on the APU that's on the truck then the truck itself, until the end of March I put it in the shop for a PM, and to have an oil leak check. Which ended up costing $6k.

But anyway, a back in January the APU stopped putting out 120vac. It would start and run just fine (after i bled the air out of the fuel line) but it wasn't putting out any current which meant all I could do was keep the engine warm and recharge my batteries. So every month when i'm home on hometime, i'll spend a couple of hours tinkering with it.

The first thing i found was that Kenworth MHC neglected to put a shut off valve on my coolant lines, which was an issue when i was replacing the water pump..
After that i had the oil pressure sending unit act all crazy for two days and kept making the engine shut off.
And then recently I couldn't even get it to start because it kept saying "Main Engine Interlock".

So after finding copies of the service and owners manual i dug deep. Found that there's a relay that control the engine interlock.. mine had seized up. Jump'd it over to test, and the APU started just fine. I was even able to buy the fuse in the Pilot for $10.

For the no voltage issue, the manual says if there's no voltage before the 35amp breaker, then the capacitor is the suspect, but the only way to test is with a good capacitor.. Kept digging through the manual and found that there's three capacitors in the actual HVAC unit under the bunk. Got down to it and pulled the large one out.. Wired it in and fired it up and got my little lighting bolt back..

I shut everything down pretty quick because i wasn't sure if it was the right size or what not. So now i have to wait until Monday to get two capacitors from the TransCarrier dealer in Florence, Sc so i can get my APU back up and running..

In all honesty if it turned out that the generator was shot, i was just going to buy another belt driven compressor and a 300amp alternator and rig in there and call it a day.

I know when i was searching google for answers as to why my Control Panel would say the main engine was on when it wasn't, i saw some other people that were having the same issue.. hopefully they make it here and read this. Labor rates are crazy!!!