When attempting to start the truck the engine cranks on its own while parked?

2000 GMC SIERRA
400,000 MILES • 4.8L • V8 • 2WD • AUTOMATIC
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BP0392
  • MEMBER
  • 1 POST
Okay. So, I had my 12v cigarette lighter plugged in too long and now half my day doesn't work nor does my radio. And when I go to start my engine while I'm parked it keeps turning itself over by itself. So, I switched it to neutral and it's starts okay. What do you think the problem is?
Aug 11, 2022 at 10:20 AM
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SQM
  • ✓Experienced Mechanic
  • 6,383 POSTS
Hello,

This could be due to a faulty neutral safety switch.
The neutral safety switch signals when the vehicle is in park and allow the engine to start.
It is located on the side of the transmission.

Here is a helpful guide:

https://www.2carpros.com/articles/how-a-neutral-safety-switch-works

I have attached a diagram below for your reference.

Let me know of any questions.
Thank you.
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Aug 11, 2022 at 4:15 PM
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