ing switch

my truck won"t turn off changed the switch shuts off sometimes & sometimes anyone know what is wrong?

 

Need a little more info...

1) What truck is it?

2) What engine?

3) Does it have the original wiring harness?

4) Does it have the original device for charging the battery (alternator, generator, etc.)

5) If #4 is "no", are you running a GM alternator?

 

What is your truck? We need more info to even attempt to help you>

 

You changed the ing. switch because you couldn't shut off motor with old switch, now it won't shut off with new either? Hard to read between the lines here!
Maybe you have a problem with how you wired the new switch................
Maybe you need a diode in line with your alternator if running one...........

 

Yep...my first guess, at least without any input.

 

I agree it could be feedback from the alternator..Here is a diagram

 

That must ****

 

Speedway catalogs sells a diode thingy, and describes it as a fix to a vehicle running when you turn off the ignition