Suburban SF35 Will not come on

Suburban LP heater was only blowing air. Removed it and cleaned out dirt dauber nests. Re installed and it would not come on. Removed again and checked all wire connections, LP gas connection, and fuse. Tried it again and still does not come on. We have a rear heater and it works fine.

What am I missing? Could it be a bad circuit panel? The unit is 10 years old.