Forum Discussion
MDKMDK
Nov 11, 2022Explorer
heyobie wrote:
Thank you guys for all the info.
There is more to the story. I didn't want to glog up my post but since I have found interest and intelligence, someone may be able to explain this.
The large positive wire comes from the house battery to a post on a selenoid which is mounted on the driver side wheel well. Then on the opposite side of the selenoid, another large red positive wire goes up and across a plastic channel over to a block attached to the passenger fender. My guess is that this is all factory but not sure. But what is not factory is a push button has been installed inside the cab on the dash. It connects to the selenoid and a power source. The push button doesn't work, but the purpose was to activate the selenoid so that the house battery power would run over to the car battery/passenger side of the vehicle.i thought it may have been a system to use the house battery to start the car. Maybe someone can explain what it is. I'm gonna pull it since it has no purpose it seems. This is probable the battery switch, but why it has a push button makes no sense to me
Sounds like a "battery boost" system, which allows you to borrow some cranking amps from the coach battery, if the chassis battery is too low to start the engine. The push button would connect the 2 systems for the duration of the starting attempt, allowing current flow from the coach battery to "help" the chassis battery turn the engine over. They're still fairly common on modern motorhomes.
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