To troubleshoot, let's break it down by symptoms:
* Car won't start at all: This is the most common symptom associated with a perceived anti-theft issue. The problem *could* be the anti-theft system, but it's more likely something else:
* Dead or weak battery: This is the #1 cause of no-start issues. Have the battery tested at an auto parts store.
* Faulty starter: The starter motor might be failing.
* Alternator problems: A failing alternator won't charge the battery, leading to no-start conditions.
* Security system malfunction: This is where the anti-theft system *might* be the culprit. A faulty Passlock system (the main anti-theft system in many 1997 Cadillacs) can prevent the car from starting. The Passlock system relies on a transponder chip in the key.
* Security light flashing: A flashing security light is a strong indicator of a problem with the Passlock system or the related immobilizer. This often requires professional diagnosis.
What to try (in order):
1. Check the obvious: Battery voltage, connections, fuses (check the owner's manual for fuse locations related to the security system).
2. Try all keys: If you have multiple keys, try each one. If one works and others don't, the problem is likely with the key or its transponder chip.
3. Have the Passlock system diagnosed: This requires a scan tool that can communicate with the car's computer system. A local mechanic or locksmith specializing in automotive security systems should be able to do this. They can determine if the Passlock system needs reprogramming or if there's a different fault.
4. Consider a professional locksmith: They are often better equipped to diagnose and resolve Passlock issues than a general mechanic. They may have specific tools to bypass or reprogram the system if necessary (this is often the last resort).
Important Note: Attempting to bypass or disable the anti-theft system yourself is generally not recommended. It can damage the car's electrical system and might even void your insurance. Always prioritize professional help, especially if you're not comfortable working on car electronics.
