Here's what you need to do:
1. Identify the Problem: The CEL is a symptom, not the problem itself. You need to diagnose what triggered the light. This typically requires:
* OBD-II Scanner: The most reliable method. An OBD-II scanner (available at most auto parts stores) plugs into the car's diagnostic port (usually under the dash) and reads the diagnostic trouble codes (DTCs). These codes pinpoint the specific issue.
* Professional Mechanic: If you're not comfortable using a scanner or interpreting the codes, a mechanic can diagnose and fix the problem. This is the recommended route if you're not mechanically inclined.
2. Repair the Problem: Once you know the DTCs and the underlying issue, you need to *fix* the problem. This could be anything from a loose gas cap (a common cause) to a more serious engine or sensor malfunction. Simply clearing the code without addressing the root cause will only result in the light returning.
3. Clear the Code (After Repair): *After* you've successfully repaired the problem, you can clear the code. There are several ways to do this:
* OBD-II Scanner: Most scanners have a "clear codes" function. This is the easiest and most reliable method.
* Disconnecting the Battery: Disconnect the negative (-) battery terminal for about 15-20 minutes. This will reset the computer, but it's less reliable than using a scanner and might not clear all codes. Also, disconnecting the battery can erase other settings in the car's computer (like radio presets).
Important Considerations:
* Ignoring the CEL is risky. Driving with a check engine light on can lead to further damage to your engine and potentially costly repairs down the line.
* Don't just clear the code and hope the problem goes away. This will only mask the underlying issue.
* A generic OBD-II code reader is usually sufficient for a 1997 Blazer. You don't need a high-end professional scanner unless you're doing advanced diagnostics.
In summary: Find out *why* the light is on, fix the problem, *then* clear the code. Relying on simple tricks to reset the light without addressing the root cause is not recommended.
