The Stovebolt Site Forums The Shop Area The Electrical Bay Leaving Ignition Switch On

This is the second time since I bought my truck In February that I left the ignition switch in the on position. The first time I burned up the coil and this past Friday while troubleshooting the gas gauge I killed the battery and burned up the points. They now are pitted and need replacement in addition to the battery being dead. Who know what else I may find!

Is there any way of protecting the ignition system from burning up, if I leave the ignition on again. Maybe a relay or diode or something?

Good question. I and am sure many others have done the same thing. I guess one could install a relay to get around this self induced error, better known as ‘operator error’. Interested in reading how others might have solved this issue.

Definitely ‘operator error’, but as my mind is aging I can see this happening again.

Someone back a while ago said to hook up a bell or something to let you know the key was still on.. not sure how that worked out. Especially since half of us are hard of hearing in one ear, and can't hear out of the other, not to mention tinitus.

If you have an alternator, you can hook up the idiot light to show if the ignition is on, but engine not running.

Or you can install an oil pressure warning sensor/switch for a light.

A simple solution could be to use a single filament 6 or 12 volt bulb, depending on your battery voltage. Solder a couple of leads with alligator clips to it. Hook one lead to coil primary, other to ground. If bulb is lit, key is on. I think that would work even with points closed but not sure as I’ve never tried it.

the coil primary has a good chance of stoping with the points open so your bulb wouldn't necessarily be ON with ignition on.

however if you want a small light /or buzzer to be ON only when ignition is ON and engine is OFF you could connect the bulb or buzzer between ignition power and the GEN. / Armature post of the generator.
when the ignition is ON and engine OFF, the buzzer / light will sound because the generator is such a low impedance compared to the buzzer / light to ground that it would have basically full battery voltage.
when the generator is producing power, the shunt relay closes and your buzzer / light would have 0 volts across it.
-s

One could put their house key with the ignition key, of course, if you never lock your house, that wouldn't work either.

Ed

The problem arises when I am working on the truck in my garage. If I was driving it, I would need to turn the ignition off to stop the engine.

I do like the idea of an idiot light. I have a 12v system and a one wire alternator. How would I go about hooking one up?

Does your one-wire alternator have a connector on it with a short jumper to the BAT terminal?

https://cdn.shopify.com/s/files/1/1461/3626/files/240-247_1024x1024.jpg?v=1474563150

Here is what I did. There is a light bulb in the ignition switch bracket which illuminates the the ignition key area when the headlights are on.
I cut the wire for that light and wired it to the "ignition-on" terminal of the ignition switch.
Now, when my Chinese-made ignition switch remains "on", in spite of the fact that the key has been turned to the "off" position and the key has been removed, the light reminds me that the ignition is still "on".
Carl

Thanks Carl, thats a good Idea. I kinda like the idiot light idea. My alternator does have another set of terminals and I’ve seen some miniature red LED indicator lights on flea bay. Now to locate a suitable spot on or under the dash. Thanks all for your suggestions.

I'm confused here.....what else is new?
Is your key locked to your ignition switch while in the on position? If so, is the ignition switch attached to your daily key ring? Meaning, you can't get into your house or fire up any of your other cars unless you have your daily key ring in hand.

No, I’m in the process of working out all of the mechanical and electrical issues, so I’m not driving it at the moment. The truck is in my garage, so the single key was in the ignition while I troubleshot the gas gauge. After going thru the grueling process of removing/installing the cluster to install a new 12 volt gas gauge, I found that the float on my new sending unit wasn’t floating which sent me off in another direction, forgetting about the ignition still being on.

If I was driving I don’t believe it would be an issue.

If your not driving it a simple solution would be to remove the positive battery cable before quitting for the day and don’t reconnect it unless working on the ign/electrical system.

I see a battery kill switch in my future. I installed one on my boat not too long ago and it works great!

I remove the negative terminal which accomplishes the same goal but It’s the recommended and safest way to disconnect the battery. The reasoning is if your loosening the bolt on the positive terminal and your wrench accidentally hits ground it will create a spark. A spark near the battery potentially can ignite the hydrogen gasses the battery generates during charging. I personally saw a battery explode in my father face while he was hooking up a set of jumper cables. It wasn’t a pretty sight. He was fortunate he was wearing large reading glasses that saved his eyes. I gained allot of respect for batteries that day almost fifty years ago.

Agree with Martin.
I disconnect the neg every time I get out of my truck. Just can't sleep at night with battery hooked up. The cable clamp is just right to put it on and twist a little. There is no cure for paranoia, so this is the only answer. A light does not work on idiots, so I can't use that.

In reading the original post, it appears that part of the issue arrises from needing to work on the electrical system troubleshooting with the ignition on (not necessarily forgotten to be turned off), in that case, I just pull my coil wire to keep power from the points. It saves them anyway. I also have a quick disconnect on the negative terminal of the battery, it makes it so easy to isolate the battery.

Lee

Are you pulling the high voltage wire or the 12v supplying power to the coil?.

I just installed a battery cutoff switch using the negative side to break the circuit. Now when I disconnect the battery when I leave the shop.

I tried to install an idiot light but I couldn’t get it work with my one wire alternator.

I am pulling the booted plug off the top of the distributor, I believe that will keep the points from getting power even if they happen to be closed (that is what I was told anyway, and I have not burned up any points yet). I just do it when I will be working with the ignition switch on for any length of time. I really like the battery disconnect switch, so much easier than getting out my half inch wrench and loosening the clamp bolt.

Lee.

I don’t think that is stopping the power that is traveling thru the points. maybe some of our experts can chime in. I also love the battery disconnect. I still got some of the old wiring so feel much better when I leave the truck.