Whats this button for??

[dolphin_tales]

I have this strange button on my dash that I am unsure what it is for. I know when I press it, this selenoid clicks. It looks like some type of master cutoff power. Can anyone tell me what its for and why its on the dash?

 

[Gary RV_Wizard]

Could well be an emergency (aka auxiliary) start switch. It switches the house batteries in parallel with the engine battery in case you need a boost to start the engine. Most motorhome have such a switch and it is on the dash or adjacent to it. Typically you have to hold it down while cranking the engine.

 

[dolphin_tales]

Thanks Gary. Now that I think about it I think the little label well above the switch may even say something like auxiliary start ;D. I'll have to check that out a bit closer tomorrow.

 

[bigskymt]

  The size of the cables on the solenoid seem to indicate aux starting as Roamer said. Is that a momentary switch (meaning push=ON, release=OFF). Does the red indicator lamp have anything to do with it?