What would cause this? Fan, fuel pump and water pump will run constantly unless the master switch is off.

What brand / model toggle switch box, relay board?

Don't know why it didn't post it but anyway its the altronics power quest touch screen

Daryl,

sounds like one of the board relays is defective. If the relays are replaceable [that is can be unplugged] remove one at a time as a test. If they are soldered in would be best to return to manufacture.