Here's the proper procedure:
1. Diagnose the Problem: The first and most crucial step is to find out *why* the check engine light is on. You can do this in a few ways:
* OBD-II Scanner: This is the best method. Buy a relatively inexpensive OBD-II scanner (available at most auto parts stores) and plug it into the OBD-II port (usually under the dashboard). The scanner will read the diagnostic trouble codes (DTCs), which are numerical codes indicating the specific problem. You can then look up the codes online to understand what's wrong.
* Auto Parts Store Scan: Many auto parts stores will scan your vehicle's codes for free. They can often give you an idea of the problem, but might try to sell you parts.
* Mechanic: A mechanic will have the diagnostic equipment and expertise to pinpoint the issue quickly and accurately. This is the best option if you're not comfortable troubleshooting yourself.
2. Fix the Problem: Once you know the cause of the check engine light, *fix it*. This might involve replacing a sensor, fixing a leak, or performing more extensive repairs.
3. Clear the Code (After Repair): *Only after repairing the issue* should you attempt to clear the code. There are several ways to do this:
* OBD-II Scanner: Most OBD-II scanners have a function to clear diagnostic trouble codes (DTCs).
* Disconnect the Battery: Disconnect the negative (-) battery terminal for about 15-30 minutes. This will sometimes reset the system, but it's not guaranteed to work for all codes. Be aware that this will also reset your radio presets and other settings.
Important Considerations:
* Don't just clear the code without fixing the problem: The light will likely come back on, and the underlying issue could cause further damage to your truck.
* Intermittent Problems: Some problems are intermittent. The light might go away temporarily, but the problem could return.
* Safety: If the problem is serious (like a failing engine component), driving your truck could be dangerous.
In short, resetting the check engine light is the last step, not the first. Focus on finding and fixing the root cause of the problem.
