How to reset my alarm
If the procedure in the owners manual don't work then try this: from the inside manually lock all the doors but the drivers, with key in hand close and using the key lock the drivers door, watch the dome light and when it goes out, wait at least one minute, then using the key unlock the drivers door and see if it will start run. If this procedure also fails then you could have some failed door switches or wiring problems in one or more doors, unfortunately it will take a shop that has all the equipment to test this system to locate the problem.
Tennisshoes is somewhat correct however, if you want an EASY and quick fix. Swing her on by the local GM dealer. They will usually recode the keyless entry and alarm for free. Many auto parts stores can do the same for you at no cost. I would call around before you have to go though all these "tricks" ... watch the dome light??? What? Best of luck!
It's not a trick, every GM vehicle I have tried that didn't have some other problem it worked, reason watching the dome light as some GM's have a delayed exit routine that the BCM follows and the dome going out is a sign that the routine has been carried out. And when has any dealership done anything for free?
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