if ou have not fixed the reason that it is on it will not go away. other than that i have reset mine by disconnecting the battery for about a minute
I opened the fuse box under the hood on my 2005 civic and pulled the "ECU" and "Backup Fuses" for 10 seconds and my engine light went away. Or do you mean reseting the "maintenance" light? That is the one that comes on as a reminder to get your car serviced and it doesn't get reset by many mechanics when they do your oil change. For that one you hold the "tripometer" button in, turn the key to the on position, wait 20 seconds, turn the car on, then release the button and the light should be reset.