2005 silverado crew cab 156xxx miles

[Jjsaenz]

Ok so i have a 2005 silverado 5.3 crewcab the truck works great. Hauls great as well ,but ever since i purchased it (pre owned) ive had this problem. I turn the truck on and it starts right away i can use it trough out the day the only problem is ,it turns off if i leave it on and not moving for more than 15 min. It shuts down and doors lock I restarted and it turns right back on but after 2 min it shuts back down and i have to wait like 20 min for it to cool down before i can drive it again, ive replaced the temperature sensor, crankshaft sensor, camshaft sensor, thermostat, but no solution. Can anybody help ??

[sahls01gmc]

Have you had it scanned for codes?