Why the anti-thief device is keeping my truck from starting?

I keep telling people you can't bypass the anti-theft system, you have to fix it. Pass Key 3 is clever, and I remember from our professional auto electronics wizard @Jeff Armer, there are a number of different Pass Key types.

You need an auto electrician, or an auto locksmith / alarm installer with a bi-directional pro grade scan tool computer. You can't fix this yourself and you don't want to be on the highway doing 70 when the engine turns off. Also bypassing stuff with bit of wire gives a real chance of damaging very expensive modules.

I would expect will need to have the OBD read and reset from there

Pt 1 2007 Chevy 2500HD Reduced Engine Power Warning Fault Code P1516... You need to take to a good repair shop that fix's this problem !

If the security light is on, the problem is with the Vehicle AntiTheft system. The key with the chip is not being read in the ignition cylinder. Therefore the computer doesn't allow it to be restarted for 10 minutes.

It's possible that you will need assistance from the manufacturer of the Anti Theft device. They may have tto reset the system, as an Anti theft device, any thing construed as 'tampering' with the car, or the device may cause it to shut down, and would need tech support from the manufacturer.

It could be your anti-thief system. Try turning your key to the on position but don't try to start the car. Leave it in the on position for 10 min. Your security light on the dash should stay on throught the process but will go out after the 10 mins. When you see it go off turn your key back off then start your car. If it starts, you just reset your anti-thief system. There are ways to bypass this system. I don't remember the web sights. Good luck.

2006 colorado..security system keeps me from starting the truck , but not every time. i had a new key made but the security symbol pops up now and then too. can the system be turned off//

Start keeping a log. This will help you and the shop if you take it in. Each time it happens, Was it Cold, Sat overnight, just finished running an errand and up to opeating temperature? these are the things that are needed to try to duplicate it to being stubborn to start.

2005 Colorado 4x4 stick shift – I had the same thing happen and it had to do with the passlock system – it will keep your truck from starting for approximately 10 minutes, yes you will have to wait and let it sit- if you try to start it will just turn over forever. On my truck the solution was to change my starting procedure, I now keep the truck in neutral-turn the key all the way for a few seconds and then push in the clutch- it starts every time. If you have an automatic I don’t know..

the computer is turning the car off and it is a thief device
you have a computer chip in your key and the computer reeds the code on it and will keep the car running. most likely your key
or chip needs to be replaced