Here's what you should do:
1. Get the Diagnostic Trouble Code (DTC): You need to find out *why* the light is on. This is done by using an OBD-II scanner. Auto parts stores often offer free code reading services. The scanner will provide a code (e.g., P0171, P0420) that indicates the specific problem.
2. Address the Problem: Once you have the code, research what it means. Many online resources (repair manuals, forums) can help you understand the issue. It might be something simple (loose gas cap) or something more complex requiring professional repair.
3. Repair the Problem: Fix the problem identified by the DTC. This might involve replacing a sensor, fixing a leak, or performing more extensive repairs.
4. Clear the Code (After Repair): *Only after you've repaired the problem* can you clear the code. Many OBD-II scanners have a "clear codes" function. Some newer cars might require a drive cycle (driving for a certain time and distance) for the light to turn off automatically after the repair.
Important Considerations:
* Don't just clear the code without fixing the problem: The light will likely come back on, and the underlying issue could worsen.
* Professional Mechanic: If you're not comfortable diagnosing and repairing the problem yourself, take your Lucerne to a qualified mechanic. They have the tools and expertise to properly diagnose and fix the issue.
* Battery Disconnect: Disconnecting the battery for a short time *might* clear the code, but it's not a reliable method and won't address the underlying issue.
In short: Focus on finding and fixing the root cause of the check engine light, not just resetting the light itself.
