How do you disarm your alarm in your 2008 Chevy Trailblazer?

To disarm the alarm in your 2008 Chevy Trailblazer, simply use the key fob to unlock the driver's side door. If you don't have the key fob, you can also insert the key into the driver's side door lock and turn it to unlock the door, which should deactivate the alarm. If the alarm continues to sound, starting the engine with the key can also help reset the system.