Originally Posted by mmwjr
Did you measure power at the breaker? If you jumper 12V to the switches does it work? If so you need to trace the wire that supplies 12 V however it could be a bad ground as well.
Switches are used in series to provide a "deadman" arrangement to protect from accidental discharge. Have you held both switches down simultaneously? just holding one won;t run anything. They both have to be depressed together.
If it still doesn't run, then here's the remaining info you asked for.
The feed to the switches comes thru the DC breaker panel at the helm.
Should be a 15amp breaker with a solid brown wire leading to the switches.
Check the voltage at the first switch between the brown wire and a good ground.