tried to start the truck after sitting for three weeks. Don't drive it much (23000 miles). Battery was dead, put the charger on after a few hours it started right up. The problem is it won't shut off. turn the key to off,take the key out of the ignition. still runs. Security lock light is on. Disconnected the battery,still runs. Finally pulled the fuel pump breaker and it shut down. Tried it a couple times still the same way.
Looked under main fuse block on fender for shorted wires etc. didn't see any shorted out. Any idea whatwould cause this. Will call dealer in the morning since it's still under warranty.

thanks

 

More than likely your ignition lock cylinder has become loose or disconnected from the ignition switch, lower on the steering column.
Once the system is up and running, disconnecting the battery doesn't help because it's running off the alternator. You'll probably find if you adjust the linkage between the cylinder and the switch it will solve your problem.

 

Have a 2006 hhr battery dead key wont come out