How long until the Check Engine light turns off after messing with the car battery?

That light shouldn't come on just jumping another vehicle, disconnect 1 battery cable for a couple of minutes and then rehook to see if the light goes out and if it comes back on you have problems and need to get the code read.

See if it goes out after a 20 mile drive. If not, disconnect the battery for 10 minutes and connect it back. Hopefully the light doesn't come back on. If it does, have the trouble codes checked.

It can take up to 200 drive cycle to turn the light off. That not the same as a key cycle a engine cycle is from cold to warm and have to go throw the readyness monitors. Easier would be to go to a shop and have them scan the code and turn the light out. Better would be to treat it as a real code because your dad could have damaged something in your car.

Test the alternator yourself to be sure. Buy a voltmeter and conect the positive needle to the back of the alternator on the possitve side B+ and the negative needle to the negative battery pole, Should read about 12.3-13.7V. If its less then its your alternator. If alternator is fine and battery light is still on, check your earth wire is tight as well as all other battery leads.

Usually after 40 cycles.... He will need to drive the car for about 20 miles until the engine re-learns how it drives.

Dr A

What happens if you hold in the check engine light reset button under the dash while starting the car?

Some vehicles have a Battery temp sensor mounted in battery tray,might have unpluged it or damaged it.

It shouldn't have gone on. Better get the codes read and go from there.

It's probably easier to take it to a mechanic and have them check it out.

Uh... it should go off right away... maybe u screwed up ur alternator or something...