T.I. tried to come to King Harris‘ rescue when he was arrested in Georgia early Sunday morning … but he couldn’t talk the cops out of booking his son, TMZ has learned.

In body cam footage obtained by TMZ … Gwinnett County officers pulled King over for “doing over 75 MPH in a 45” in a Cybertruck. T.I. and Tiny‘s son said he didn’t know he was speeding … but didn’t budge from the driver’s seat when the cops asked him to get out of the vehicle.

King sat in his Pikachu onesie as an officer explained that he was trying to separate the rapper from a firearm that was allegedly in the car.

After refusing to get out of the car quite a few times — and a couple calls to his lawyer — King was arrested for willful obstruction of law enforcement officers.

The cops cuffed King and used his phone to call someone to pick up the car and the gun from the scene … and T.I. arrived not long after.

The “Whatever You Like” rapper asked the cops if they could resolve the issue right then and there … but they weren’t biting.