The 24-year-old IT analyst has admitted the crime, said police, for which he could face up to six years in jail.
Motorists were left in shock last week when footage from a Japanese porn film was displayed on an electronic screen in south Jakarta.
The video ran for five minutes on Friday before power was eventually cut.
However the clip had already been captured on many mobile phones and soon spread across social media.
The man, who was arrested in his office, allegedly carried out the prank after seeing login details displayed on the billboard.