Todd Sween

My heater is a six gallon Atwood. The problem is that the wiring diagram shows the colors of the wires going “to” the RV but no colors for the wires coming “to” the heater connections from the RV. In fact, the colors do not match each other. The main puzzle for me is the green wire (5) is shown on the schematic as to ground on the RV chassis but is also noted -12volt ! Where do I find and what is a -12 volt connection ? It’s giving me a headache. Thank for any help getting my elec heater working.

I bought my ACE motorhome late last year. I’ve just replaced my tank after a winter freeze tank breakage. I’m not sure if the (elec) water heater was working prior to buying the RV so now I have an “issue”. I reconnected all wiring as I found it but, when I connect the Green from the control card to the -12v from the RV I blow the heater fuse. Any ideas?