* Faulty Security System Module: This is the most common culprit. The module itself might be malfunctioning, causing the light to flash.
* Bad Passlock System: The Passlock system is part of the anti-theft system. A faulty Passlock sensor or module can trigger the flashing light and prevent the car from starting. This is particularly likely if the car is struggling to start.
* Low Battery Voltage: A weak battery can sometimes confuse the security system.
* Damaged Wiring: Wires related to the security system can get damaged or corroded, leading to malfunctions.
* Incorrect Key: While less likely if the car has started before, make sure you're using the correct key.
Troubleshooting Steps:
1. Check the Battery: Make sure your battery is properly charged and the terminals are clean and tight. A jump start might temporarily resolve the issue if it's battery related.
2. Try a Different Key (if applicable): If you have a spare key, try starting the car with it.
3. Wait: Sometimes, a temporary electrical glitch causes the light. Try waiting a few minutes and then trying to start the car.
4. Consult a Repair Manual: A repair manual specific to your 1996 Buick Regal will give you diagrams and troubleshooting guides for the security system.
5. OBD-II Scanner: While the 1996 Regal might not have a fully compliant OBD-II system, a scanner might still pick up some codes related to the anti-theft system.
6. Professional Mechanic: If the problem persists after trying these steps, you'll likely need to take your car to a qualified mechanic specializing in older vehicles. They'll have the tools and expertise to diagnose and repair the security system properly. They can test the system components and pinpoint the exact cause of the issue. Replacing the security system module or Passlock components is often the solution, but it needs professional diagnosis.
Don't attempt to bypass the security system yourself; this can be dangerous and might further damage the system.
