When non-essentials are cut off with Start, how does the solenoid power stay on when in MOM, but not otherwise?
The ignition switch only energizes the solenoid when the switch is in DUAL position.
When the rocker switch is held in MOM the ignition switch is not involved at all. The house batteries are used to energize the solenoid.
This is my understanding, anyway.
The rationale is this:
When holding MOM, you are jump-starting the presumably dead engine battery using the house batteries. So clearly you need to energize the solenoid from the house batteries. And you only want them ganged as long as it takes to finish the jump-start, hence the momentary nature of the switch.
In Dual, the goal is to charge the house batteries, but not run down the engine battery if the engine shuts off. Thus the ganging is only going to happen if 1) the switch is set to DUAL and 2) the key is in RUN. This way if you arrive at camp and have had the switch in DUAL to charge your house batteries and you shut off the engine you won't accidentally leave the house ganged to the engine and thus possibly deplete both sets of batteries while you are camping, and then find yourself stranded.
Steve
