10-26-2024, 05:48 AM
Tne new 300 901 control unit has pig tail plugs vs the three plugs mounted into the Botton of older control units. Your "B" and "C" plugs are plugged in correctly. Since you have an Aqua Hot heater and do not have a Webasto Heate Exchanger, which are used in some Prevost conversions, you do not need the "A" plug. So, the "S" plug just sits there getting your attention.
Rudy Legett
2003 Foretravel U320 4010
ISM11 450 hp Allison 4000R
Factory Authorized Aqua Hot Repair Center
Southeast Texas Area