Help adding a second switch to a 12 volt DC motor circuit

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Thread Starter


Joined Sep 29, 2011
I'm having a bit of trouble with a project I have going on. I'm installing a key switch on the outside of my bus, so I don't have to walk around and climb over the driver seat every time i want to open the doors. (other switch is on the inside)

Right now the circuit has one double pole double throw switch that goes into what i think are two relay switch things :confused:, that are hooked up to the 12 volt DC motor that opens and closes the door. I wanted to put another switch into the circuit. (key switch for outside) I Have the switch wired up what i feel is correct. but if i hook up my switch the other switch stops working.

This is the switch I'm trying to put in.

I've also included what I feel to be a horrible diagram of what I've done. :) door wire diagram.gif

sorry its not the most interesting project but, I'd like to say thanks to anyone who could lend some info and help me out. Much appreciated.


Joined Jul 9, 2011
I've also included what I feel to be a horrible diagram of what I've done. :)

Just to confirm: switch 1 is the one that is installed, and switch two is the additional one?

Question: From switch 1 the orange and blue lines, is the voltage on them always ON, meaning is the voltage only being inverted when the switch is activated/deactivated? Or does it turn completely off?

If it's only inverted you can put a switch with the same function in series with this first one. see attached picture


Thread Starter


Joined Sep 29, 2011
The orange and blue lines are turned completely off. The switch must be used to have current pass through them. They both have a center off position. Left and right swith polarity. Thank you for the schematic though.
The line from the battery will be the only "active wire" is there another way I should have wired this? The switch works, it just seems like I can't get them to work wired up together.

Thank you do your reply!


Joined Apr 5, 2008

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