check engine light with no codes
hello, looking for some help/advice. i have a 97.5(98) TJ and I tried the key check maneuver to find the error code for my CEL being on and no code appears. i only see the mileage on jeep, and no lights flash on and off.
am i doing something wrong? i turned the key position on>off>on>off>on, and then waited up to 5 mins. i don't know if i need to wait longer or do anything else. please help.
also, what is good to remove corrosion build up on battery terminals?