How to Turn off the Check Engine Light

While driving from TN to TX, the check engine light came on with 10+ hours left to go. The manual says to check the gas cap. That was on securely. Is there a simple way to find out the problem/turn the light off?
(The maintenance req light is also on but the oil was changed 6 months ago and has plenty in the holder).
Thanks for any suggestions!

Some auto parts stores will connect a code reader to the vehicle and get the code(s) that’s causing the Check Engine light to come on for free. They’ll also use this tool to turn off the Check Engine light.

But unless you repair the reason the Check Engine light is coming on, it’s just going to come back on again.

But whatever you do, don’t disconnect the battery to turn off the light. On some vehicles this can cause all sorts of problems. Like causing the anti-theft system from preventing the engine from starting


Most cars will tolerate a battery disconnect without any problems…Some high-dollar imported models may forget important things…You can buy a OBD-2 connector to USB cable and use a free diagnostic program to scan and reset your ECM with a laptop…

Tester is right on, if you just manage to turn the light out but not fix the problem you might as well put black tape over the light so you won’t notice it. The light is telling you something. The maintenance required light could be a simple ‘timer’ telling you that x miles have passed since your last oil change, or it could be a more complex system that measures stop/starts/run time etc to determine when the oil needs changed, depends on the car. Typically the maintence light is for oil changes, you can make it home OK, but you should plan on changing the oil and filter soon. Since both lights are on, it is worth getting the code read to see what the issue is and getting it taken care of by your local shop.

It’s possible the problem is indeed a loose gas cap. Remove it, make sure the seals are not dried out, and if everything looks ok screw it back on. That might solve the problem.

But it may take some time – even a few days of driving – before the check engine light goes off. For potential emissions problems like a loose gas cap, the gov’t says the computer has to be convinced the problem is fixed before it will turn off the light.

As said above, most folks – before worrying about turning the light off – would take it to a shop or an auto parts place that will read the codes (some will do it for free) and find out what the reason is for the CEL coming on. If it is something benign, no worries. But if it is something that might prove expensive if ignored, better to know that info asap.