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Trunk shut off switch

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Bob Claffie

Bob Claffie

Jedi Knight
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Can that simple switch be wired backward? My newly installed switch will turn off the engine if switched while the engine is running but doesn't affect any of the other electrics one way or the other. Thanks, Bob
 
Well Bob . The black and white wire at that switch cuts off the ignition circuit at the coil. Properly it should only ground the coil when the switch is in the off position. However, if you switch the switch while the engine is running you should also break the ground circuit to the battery.--Fwiw--Keoke

P.S. Disconnect the battery hot lead. Take an ohm meter and check the switxh. Across the two large terminals it should go from closed to the open position when switched off. The black and wite wire should also show a ground only when the switch is off.

Perhaps the main swith is not opening in the off postion and the B/W wire is stopping the engine.--?
 
Perhaps I misunderstood the purpose of this switch. It acts as described above by Keoke. I THOUGHT it was supposed to totally disconnect the battery from the circuit disabling all the electrics by breaking the ground. As I think about it, is it breaking the ground OR making the ground of the coil wire? I guess I am too lazy to go out to the garage and look at the wiring diagram. Bob
 
Bob,

That switch is supposed to do both when it is working properly.
It opens the connection between the two big screw(terminals) when the switch is rotated to the off position. Also when the switch is in the off position, it connects the small terminal for the white/brown wire to the one big screw(terminal) where the ground braid attaches that goes to the frame ground screw in the boot. This is an early form of theft protection. The points are grounded and won't work plus the battery is disconnected so the starter will not work. The battery is disconnected ( nothing attached to ground ) when the switch is in the off position. If you still have electricity when the switch is in the off position, then either the switch is bad or something is wired wrong to the ground side of your battery.
Ed
 
My understanding is that it disconnects battery from all circuits, which is why I try to remember to put the switch in the off position when I'm working under the hood. I've experienced touching live circuits with a tool...not good.

And yes, it does provide some level of theft protection.
 
Could it be working "incorrectly" since I did change the polarity of the car? Sorry about mentioning that earlier.Bob
 
The switch is not polarity sensitive.
It will work the same no matter which way your ground is.
Ed
 
Bob Claffie said:
Could it be working "incorrectly" since I did change the polarity of the car? Sorry about mentioning that earlier.Bob
Click to expand...

No Bob, the switch is not polarity sensitive. Did you check it out with a meter??---Keoke
 
No, no testing yet. Weather has been wicked wet and I am not in that much of a hurry. Supposed to dry out early next week, soon enough to find out. Here in Mass we are looking to put our sporty cars away for the winter already. I expect the semi-restored AH will not hit the pavement until spring. Bob
 
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