# Ignition on voltage



## Audioi (Dec 21, 2020)

I am installing some heated grips and using a relay to supply the 12VDC direct off the battery, Where is the best place to pickup the 12v positive from the ignition switch without hacking up the factory harness?


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## RikP (Jan 19, 2021)

Hi,
I do not think that you will get 12v+ from the ignition switch as it's only shortcut the ignition coil. 
Depending of your model, there is an other coil responsible to provide power to the lamp. Wires should exit to the right side of the engine. You will need to split from there.

Maybe someone else has a better solution.

Erik


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## ST1100A (Feb 7, 2015)

First off, what model do you have?
The ignition switch normally only grounds the ignition to stall the engine.
The ignition is powered by the magneto, so that will not power lights or hand grips. You would have to hook it to a 'Lighting Coil' wire that is totally separate from the ignition.
If you have a 12 volt battery, that was used for powering the electric starter and that only got power when you turned the key to the 'Start' position. When you turned the key to the 'Off' position, it only grounded the ignition coil.
If there was an 'Accessory' terminal on the key switch, that would give you the 12 volts when the key was set to the 'On' position. The accessory post would power something like an engine 'hour Meter'.
The separate 'Lighting Coil' only works when the engine is running from the magnets in the flywheel spinning past the stator to produce the electricity for the lights, which in most cases is A.C. current. If there is also a 'Charging' lead for the battery, that is A.C. current rectified to D.C. current with a little inline Diode to the battery.
You will most likely 'Hack up' the factory harness to install what you want to do with it. You should get a service manual for your machine, it will have the wiring diagram in it so you can see which wires are what and may show you what you can tap into.


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## Audioi (Dec 21, 2020)

ST1100A said:


> First off, what model do you have?
> The ignition switch normally only grounds the ignition to stall the engine.
> The ignition is powered by the magneto, so that will not power lights or hand grips. You would have to hook it to a 'Lighting Coil' wire that is totally separate from the ignition.
> If you have a 12 volt battery, that was used for powering the electric starter and that only got power when you turned the key to the 'Start' position. When you turned the key to the 'Off' position, it only grounded the ignition coil.
> ...


Sorry I have a HSS1332


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## tabora (Mar 1, 2017)

Here's the wiring info for the Hour Meter. Pick up the "running" volts on the blue wire. (At least that's what I'm planning to do.)

HSS1332ATD Hour Meter Wiring

Red - "Battery"
Blue - "LED" connects to the LED terminal on the ignition coil
Lt. Blue - "Pulse" connects to the auger protection switch
Black - "Ground"


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## Audioi (Dec 21, 2020)

tabora said:


> Here's the wiring info for the Hour Meter. Pick up the "running" volts on the blue wire. (At least that's what I'm planning to do.)


Thanks for the diagram, very helpful! I will send photos of the finished product.


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## ST1100A (Feb 7, 2015)

You could go right off the key switch 'LO' terminal, that would give you 'Key On' power from the battery.
The 'LO' doesn't have a wire so you would have to install one. 'LO' on other machines sometimes stood for 'Local' which was an abbreviation for 'Local Power', which was battery power for an accessory when the key was turned to the 'On' position.
Other cases the 'LO' stood for 'Light Option/Light Output'. Different manufacturers used different terminology terms.
Like Tabora mentioned, the LED terminal would only work when the engine is running so that will save on your battery if the engine stalls but the key is left in the 'On' position.
Looking at the wire diagram the 'Blue' from the ignition coil should be a 'Signal' wire to the 'Engine Hour Meter'. That is a low voltage signal wire to make the meter count the time the engine is running. That would probably not be enough power for accessories and would mess the hour meter timing count up.
The hour meter counters work by taking a pulse signal from the ignition every time the engine fires and goes into a counter to add up the time the engine is running.
At 3600 rpm's for an hour straight that will give 1 operating hour. That can change if the engine is not spinning at 3600 rpm's. It calculates it to give the operating hour time for the display.


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## ST1100A (Feb 7, 2015)

If you are going to use a relay, hook your wire to the 'LO' terminal on your ignition switch from the relay. If you hook it to some of the other wires like the 'blue 'LED' wire, you will get a 'pulse' that wont be enough power to trip the relay, and if it would, it can burn out the relay quickly because it will make it turn on and off constantly while the engine is running because of the 'pulse' signal it will be getting instead of it remaining powered on steadily when the key is on.
The relay needs a steady D.C. power source, not a 'Choppy' A.C. type like the hour meter signal or the lighting coil/charge coil would put out before it is rectified to a smooth steady D.C. source.


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## Audioi (Dec 21, 2020)

Thanks ST1100A for the info! I was planning on checking out the switch tomorrow, saves me the time.


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## Audioi (Dec 21, 2020)

Got the grips installed! Took longer than expected but I’m really happy with the install. I built a fused wiring harness and made everything look as close to a factory install as possible. I cleaned up the factory harness routing. The high-voltage runs through the relay heavy side and the relay is powered from the ignition switch through the grip switch which lights up Red when they are on. The grips are 1 inch diameter so no shims were needed.


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## Audioi (Dec 21, 2020)




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## Spyle (Oct 24, 2017)

What brand and model did you use for your heated grips? I have got the HSS1332 also and I'll have a look....


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## Audioi (Dec 21, 2020)

Spyle said:


> What brand and model did you use for your heated grips? I have got the HSS1332 also and I'll have a look....


Made for MTD / Ariens. I wanted something that was 1 inch on both sides and these are all I could find. No thermostat control like those made for motorcycles but they work great. I insulated the inside of the bars before hi temp epoxy/screwing into place.









Amazon.com : Mtd 753-05762B Snowblower Heated Hand Grip Kit Genuine Original Equipment Manufacturer (OEM) Part : Patio, Lawn & Garden


Amazon.com : Mtd 753-05762B Snowblower Heated Hand Grip Kit Genuine Original Equipment Manufacturer (OEM) Part : Patio, Lawn & Garden



www.amazon.com


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## Spyle (Oct 24, 2017)

Audioi said:


> Made for MTD / Ariens. I wanted something that was 1 inch on both sides and these are all I could find. No thermostat control like those made for motorcycles but they work great. I insulated the inside of the bars before hi temp epoxy/screwing into place.
> 
> 
> 
> ...


Many thanks,

Appreciated.


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