Hello all, new member. I'm in need of many minds on this. I have a 2014 Chevy Express 4500 RV. Last year it began intermittently not starting. We had it towed to a shop, and they installed a "hot wire" button, for lack of a better term. Also last year (after that fix) the A/C stopped blowing cold air. Had that issue looked at and was told freon is full and the compressor was not locked up and appeared to be in working order. I have even replaced the ECM, and the problem still persists. Has anyone else had these issues, or have an idea of what could be going on. Thanks in advance. And apologies in advance, as I don't have a lot of vehicle mechanical knowledge.

 

Probably the temperature blend door isn't working.
Check your fuses.