changed ignition switch car won't start?

You replaced the part the key cylinder goes into?

If so you have to relearn the pass lock sensor. Make sure the battery is fully charged. Then try to start it then let the key sit in the run position do not turn it off wait ten minutes until the security light stops flashing or turns off. then turn it for thirty seconds then repeat two more times then it should start. Let me how it goes.

I am having the same problem my car starts but shuts off withing 1 or 2 seconds and my security light is blinking amd I've tried to do the bypass where you leave the key in start for 10 minutes but the security light will not stop blinking or shut off .....my car was stolen by i got it back and they destroyed my whole steering column I just replaced it and everything is wired properly it's just this security thing I can't get past

Hi and welcome.

You need to relearn the key cylinder to the PCM. This is how you do it:

Turn the key to run. Do not crank it. Leave it on for about 10 minutes until the security light blinks (or) Goes out. Turn the key to the off position for 10 seconds and then repeat above.

You will do this 3 time for a total of 30 minutes. At the end of the 3rd time start the car instead of turning the key off.

You may also use this guide if it helps.

https://www.2carpros.com/articles/how-to-reset-a-security-system

Let me know if this helps.

Rich

Hello, my car was recently stolen and I got it back. they destroyed my whole steering column and I had to go and put another one in everything is wired in correctly now, but when I go to start my car it's turns over and stops within like two seconds meanwhile the security light is blinking. now I have tried the oil reset button but that did not work and I tried leaving the keys on the start position for 10 minutes but the security light just won't go away. In all the explanations I have read it says that it should stop blinking after 10 minutes and then to turn it off and repeat twice more three in all. I would like to know am I still supposed to turn key off even if the light has not stopped blinking or turned off? And is there any other way I can fix this? i do not have much money for a mechanic.

Welcome to 2CarPros. We are sorry for your troubles. This should be a free easy fix. Just follow the instructions in this guide and you should be up and running again.

https://www.2carpros.com/articles/how-to-reset-a-security-system

Let me know if this works for you.

Rich

Well it has nothing to do with my car alarm it is the security light it keeps blinking!

If the security light is blinking the security system is engaged.