what is this switch for

[John Hennessey]

On the console at the left of the steering is a switch just left of the engine brake switch on our 2003 Marquis.  It has a zigzag symbol.  Can anybody tell me what is it for?  I looked in the manual and can't find it.  My husband suggested maybe for a heater?

[Richard And Babs Ames]

Battery Parallel Switch - It is a momentary switch that unites the power of both house and chassis together for extra starting power.

or

It could also be the outside rear view mirror heat switch which is not a momentary switch.


IF you push it and it stays switched, it is the mirror switch.  If it switches back when you let go, it the parallel switch.

[John Hennessey]

THANKS, hope I never have to use it

[Joel Weiss]

On ours I know that is the heater switch for the mirrors.

[barbhalsell]

Just went out and sticky noted our switch. I dont think we knew what that was either LOL!

[Gerald Farris]

John and Linda,
The battery parallel switch or boost switch that ties your house and coach batteries together should have a picture of a battery on it. The switch that you described with a zigzag pattern on it is the switch that turns on the heater in your outside mirror. Like you said, hopefully you will never have ice or snow on your outside mirrors where you need heated mirrors, or a dead battery where you need the boost switch, but you should know that they are there if you do need them.

Gerald

[Joel Weiss]

. Like you said, hopefully you will never have ice or snow on your outside mirrors where you need heated mirrors, or a dead battery where you need the boost switch, but you should know that they are there if you do need them.

Gerald

Gerald:

It may be worth noting that the Patriot Thunder supplement to the owner's manual says to use the boost switch whenever the engine is started.  I usually remember; I figure there's no harm in doing so.

Joel

[Joel Ashley]

I think it depends on whether the solenoid involved with tying the battery banks together is designed for frequent or prolonged use;  most are not, can wear out or carbon up, and may not be there when your chassis batteries need help.

Joel

[Ken Buck]

My '07 has both a pictograph and an explanation of what each switch does.  I've attached pictures of some of them.  Maybe that will help someone to understand what the pictographs mean.  I never would have guessed on some of them.