Diesel keeps running but strangely

[Muledeer2]

So I got home tonight and went to shut down my 1990 cat diesel pusher, and it would not stop running, but it was like just barely running and shaking really badly, get this when i turned off the park lights the engine stopped, so I started it turn on the headlights and shut it down and it was fine, restarted it turned on the park lights and guess what engine kept partially running, like the fuel shutwon solenoid is getting some voltage to keep it partially open...........Strange for sure and it does it everytime when the park lights are on, but i have to check again it could be the dashlights, i recently replaced the headlight swith because it was getting hot and i also changed out all the lamps to LED's on the coach but not in the dash lighting. Somehow the park light circuit is back feeding into the ignition circuit but where is the big question.

Any thoughts?
muledeer2

[Muledeer2]

update can't duplicate the problem again, everything works fine now, so now what?

[Skip426]

About all you can do is check the dash grounds, and wait; for the problem to happen again.
At least you have a way of shutting the engine down , so it could be worse.
Park lights are on when the head lights are on , but you say the problem was only when the light switch was in the park position .Now I'm just as confused as you are.