* The ignition system: The primary deterrent is the ignition system itself. The ignition switch is part of the anti-theft system; it's tied into the car's wiring and circuitry, making hot-wiring more difficult.
* The Passlock System (if equipped): Some 1991 Camaros *might* have had a rudimentary Passlock system, a resistor-based system. This wouldn't be a separate module, but rather a resistor embedded within the ignition system's circuitry. This system makes it harder to start the car with a non-matching key. It's not a sophisticated system compared to later versions.
* Alarm system (if installed): If a factory or aftermarket alarm system was added, that would have its own control module, typically located somewhere hidden within the car's interior. The location would vary greatly depending on the specific alarm system installed. Common places include under the dash, behind the glove box, or even in the trunk.
Therefore, there's no single "theft deterrent module" location to look for. The anti-theft features are integrated into several parts of the car's electrical system. If you're looking for a specific component, you need to specify what part of the anti-theft system you're interested in (e.g., the alarm system control module).
