Engine Running Signal

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69valiant21

69valiant21

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Im doing a bit of rewiring and Im putting in a rocker switch ignition switch in parallel with the key ignition switch. I am also wiring up a sniper with the hyperspark setup.

The rocker switch is 3 position. OFF. Latch ON. Momentary ON
For those of you who know the sniper know that the switch 12V source needs to be on while the vehicle is being cranked and while the engine is running. This switch maintains the 12V on the latched on pin while in the momentary on position. So no worries there.

The rocker switch has 2 lights. One is independent and the other is dependent. The dependent light will turn on when the KEY is turned to the ACC or run position (Pin Q2) AND the rocker is in the latch on position. What I want the independent light to do is turn on when the engine is NOT running so you know when you should push momentary side of the rocker (Starter).

So my question is: Is there a voltage signal from the sniper OR anywhere else in the ignition that is only high when the engine is running? Or not running which is pretty unlikely. I would run the signal on a normal closed side of a relay.

I hope that made sense. I have attached a couple pictures to help explain.

Key Ignition Switch.jpg


Panel.jpg
 
Got an answer from another forum, the oil pressure switch will do what I am looking for.
 
I have zero understanding of what you are trying to do here. But the oil sender circuit "is not high" when the engine is running. In order to do that you'd have to run a DIFFERENT type of oil switch, often known as a "Hobbs" switch. They normally have two terminals, so that you can run a battery source TO them, and have them pass that power on when closed/ pressurized. This is the opposite of an oil switch, which grounds when there IS NO oil pressure.

HOW THE OEM oil sender is wired: Power comes off the switched side of the ignition power circuit (IGN1 or "run") and goes TO the oil lamp, and THROUGH the lamp then out the sender wire and into the engine bay, and terminates at the oil sender. When the sender has no pressure, it grounds, causing the lamp to light.

What this means is that if you try to use that power for something else, the load on the circuit will cause your oil sender lamp to light, or "try to" depending on the load. Basically all you have there, is an ignition power source in series with a lamp
 
I am rewiring the whole car, so the switch will work how I need it to. I dont need the lamp since I have a gauge. I will run 12V from Q2 to the positive side of a relay coil, the negative side will run to the oil pressure switch. So when the key is on but the engine is off the switch will be made (Normally closed switch) thus the relay coil will be activated. When the engine is running and oil pressure is made the oil pressure switch will turn off and so will the relay coil.

SO a relay with a NO and a NC contact will work perfect. When the relay is on (no oil pressure) the NO contact will be made, which will run to the light on the rocker switch telling me or whoever that the engine can be started. When the engine is running and the relay turns off, so will the light on the rocker switch, meaning the engine is running so dont try to 'start' the engine since its already running.

I am going to take it a step further and wire the relay in to the starter relay circuit so the starter circuit will be dead when the engine is running so there is no chance that the starter can be energized while the engine is running.

Simple relay logic.
 
I still have zero understanding of what it is that you are trying to accomplish. What does all this do that you need it?

Or are you deaf and cannot hear the engine run?

You may find that you need an isolation diode in the relay coil circuit.
 
This was my post on the other forum, hope that makes a little more sense for you.

Wiring up my '69 Mopar with Sniper & HyperSpark. Wondering if there is any decent +12V signal that says the engine is running (not just cranking). I'm going with a push button start and want to do some relay logic to disable the starter from engaging while the engine is running.
 
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