Ignition Cylinder issue

Someone tried to steal my Tahoe, thank god they failed but they screwed up some stuff. Truck ran fine before, no problems at all. I had to replace the ignition cylinder, and it wont stay running, it acts like it wants to start but dies a second later. There was a small sensor on top of the lock cylinder housing with 3 wires that was broke out, it didn't look messed up bad, so i tried to put it back on, would that sensor cause no start, what the hell is it anyway. oh and the illuminated gear indicator on the gauge cluster stays on with the key off. Any and all ideas welcome, I will try anything, I need to get this truck running, thanks.here are some pics of the three wire sensor.41024

41025

This may be a security system problem.

Does the truck start up normally and then stall a second later?

Do you have a "Security" or "Theft" light that stays on (may be blinking) after the truck stalls?

If so try this, attempt to start the truck and let it stall but DO NOT turn the key back off. Instead wait to see if the security light goes out (this may take 10 minutes or so) and if it does turn the key off and then attempt another start.

Without seeing the truck or knowing exactly what is happening this is the best advice I can give right now. Try it and let us know.

Someone tried to steal my Tahoe, thank god they failed but they screwed up some stuff. Truck ran fine before, no problems at all. I had to replace the ignition cylinder, and it wont stay running, it acts like it wants to start but dies a second later. There was a small sensor on top of the lock cylinder housing with 3 wires that was broke out, it didn't look messed up bad, so i tried to put it back on, would that sensor cause no start, what the hell is it anyway. oh and the illuminated gear indicator on the gauge cluster stays on with the key off. Any and all ideas welcome, I will try anything, I need to get this truck running, thanks.here are some pics of the three wire sensor.41024

41025

the ignition key has a device that the ignition cylinder lock sensor must communicate with . the engine will start then quickly die with the security system messed up.

the shift indicator light maybe a part of this sercuity issue.
when the vehicle is turned off for a time this is slightly lit. then after a short period of time goes out..seems to be the same time the security light stops flashing..