Hi Benito,
The first thing I would do is make sure that the remote vehicle start is enabled in the drivers information center. If it is enabled, here is a list of things that will prevent the remote from starting the engine:
The RVS system will not operate if any of the following conditions are present:
The only way to determine which one is preventing it from starting, is to take it to a dealership where they can use a Tech2 scanner to view what is disabling it.
If you need more info, just ask.
Thanks,
Butch
Master ASE Certified Technician
Master ASE Certified Technician, 10 years experience, 60+ GM certificates, 150+ GM training courses