* Passive anti-theft system (PATS) - This is unlikely in a '96 Cavalier. PATS uses a transponder key to communicate with the car's computer. If the key isn't recognized, the car won't start. There's no way to "unlock" this; you need the correct key. Getting a replacement key usually involves going to a dealership or locksmith with proof of ownership.
* Alarm system (aftermarket or factory): This is a separate system that usually triggers with unauthorized entry or tampering. It might have a key fob to disarm it, or a physical switch hidden somewhere in the car (check the owner's manual or look for small switches under the dash). Disarming usually involves using the key fob or a specific sequence on the switch.
* Steering wheel lock: This is a physical device that locks the steering wheel. You unlock it using the key.
* Other security measures: Some Cavaliers may have had additional aftermarket anti-theft devices installed. These could include kill switches, hidden ignition cut-offs, or other devices that require a specific method to bypass. There's no way to know without more information.
If you are not the owner of the vehicle, attempting to bypass any anti-theft system is illegal and could result in arrest.
To unlock the anti-theft system (whatever it might be), you'll need to:
1. Check the owner's manual: This is the best place to find information about any factory-installed anti-theft systems and how to disable them.
2. Examine the car carefully: Look for any aftermarket alarm system keypads or switches.
3. Try your keys: Make sure you have all the keys associated with the car and try them in all applicable places.
4. Contact a locksmith: A locksmith experienced with older vehicles can often help with key problems and bypass simple alarm systems. But they'll need proof of ownership.
If you're locked out of your own car, and have proof of ownership, the best and safest course of action is to contact a locksmith or the relevant authorities (in case of a suspected theft). Attempting to bypass security systems without the proper knowledge is dangerous and potentially illegal.
