Chevrolet Cobalt won't start due to anti-theft system on Chevrolet Cobalt

Some Chevrolet Cobalt owners report experiencing starting issues related to the anti-theft system, often indicated by the Service Theft Deterrent System message. These problems may arise from a malfunctioning anti-theft system due to a dead battery or key issues. Additionally, using the wrong key or key fob can trigger the system, preventing the vehicle from starting and necessitating a reset. Owners have also noted that if the incorrect key is detected, the system blocks starting actions to protect the vehicle. In some instances, simply restarting the car with a functional key fob can resolve the issue, provided the fob battery is working and the primary key is used. However, if the anti-theft system continues to hinder starting, owners may need to utilize a scan tool for diagnosis and resolution. It is crucial for owners to address key-related problems and system malfunctions to effectively troubleshoot these starting issues.