Weird electrical issue

[toxicroadkill]

Something I ran into yesterday, that is to say is very weird. I have a 1986 M1009, it has been converted to 12v system. Installed a USB charger port, and a aux cig lighter port. We went on a 120+ mile road trip to pick up some fenders, and since it was in the mid 90's in central Illinois, it was miserable out, turned the air on (opened the back window), and took along a coleman cooler that plugs in the cig lighter, you know one of those deals, that can heat or cool. They work on the principle of 2 dis-similar metals joined, give it juice and it gets cold on one side, reverse the polarity, and it heats. So we get to our destination, I turn of the k5, and it wont shut off, im like that is weird, never done that before, after about 20 seconds it finally shut off. Kinda dismissed it to the heat and a long drive. But is still bugged me why it did it. Later on the way back home, stopped at mcd half way back for dinner. And it did it again...then it hit me, it was the cooler causing the problem. I had wired the cig lighter aux into the circuit that shuts off with the key. Those coolers also work in reverse, if you heat one side up, and cool the other, it generates electricity (small ammount), since it was still quite hot out, and the cooler inside was still nice and cold, it generated power, and that fed back through the lighter plug, and since the only thing on was the engine, the only real power draw to speak of, was the solenoid for the fuel shut off, the cooler actually generated enough power to keep the solenoid engaged for a short time.

Tested my theory, turned the key off a few times, and it stayed running. Turned the key off, and immediately pulled the plug for the cooler, engine immediately shut off, without the cooler plugged in, it shut off as it should.

Thought I would mention this, totally bizzare, never would dream a cooler would generate enough power to keep the thing running.

 

[Curtisje]

Interesting. Thanks for sharing.

 

[MarcusOReallyus]

This is why you should NEVER wire an accessory into an existing circuit. You have no idea what effect it might have.

ALWAYS run to the battery or a power terminal (like the one on the firewall) for accessories.