several options:
1) invest in an obd2 code reader that is able to cancel/delete CEL codes.
2) disconnect the battery for at least 30 seconds (but you will lose all your presets)
3) find out where the ecu fuse is and pull it out to reset the ecu.
note: option 3 will wipe the codes from memory, and option 2 will not, so if you have mandatory emissions testing, option 2 might be a problem if they check for past codes still in memory.