2018 KW T 880 tri axle dump truck w/ x15 cummins

1. 
   Hello,
   I have a new KW dump truck with less than 30,000 mi.
   
   Last week found there was no electric:
   - no lights, signals, flashers, etc (except for my outside strobes, and the switch controlling them)
   - none of the instrument panel worked including speedo, tach, any other guages (except for my radio, cb)
   - pto would not engage
   - power windows did not work, nor did the power mirrors
   - no ac, however the fan would blow air
   - no interior lights when the door is opened (however the overhead lights worked at the little pushbutton switch)
   
   Fuses and relays are all good.
   
   
   About a month ago the pto did not work and after pulling apart the firewall electrical connections, using some di-electric grease and reconnecting, the pto began to work. Had heard about moisture getting into the connectors and causing problems.
   
   I tried again, with making sure all the connections are tight with no result.
   
   Took the truck to the dealer and they have it for 6 days now and they don't seem to have a clue.
   Said they are speaking to Kenworth and doing what they say to check/ do but still.... no answers for me. Frustrated trying to get any answers from the dealer and finally called KW customer svc... and now they say I have to wait for the district service mgr to call me within 3 days.
   
   
   Any ideas from you guys what this could be?
   
   Thanking you in advance,
   
   J. K. Lockridge