Honk if you’re hot and bothered!

Drivers on a Michigan highway got an unexpected peep show late Saturday when an electronic billboard played porn for up to 20 minutes before going dark, cops said.

Police in Auburn Hills said the hard-core footage appeared at about 11 p.m. on an electronic billboard that faces both north and south along Interstate 75 before officers got in touch with the Toronto-based company that owns the sign and shut it down.

“We believe that the video may have been playing for at least 15 to 20 minutes before it was turned off,” police said in a statement.

It’s unclear exactly how many motorists or underage passengers saw the video, but multiple people called 911 to report the shocking skin flick, WDIV reports.

“It was very bizarre,” driver Chuck McMahon told the station. “I thought maybe it was a billboard for a strip club or something.”

McMahon continued: “I was just looking up at it and I was like, ‘Huh, oh, wow. That’s porn.’”

The operator of the sign was identified by police as Triple Communications, a subsidiary of Triple Properties, Inc., which owns the Pontiac Silverdome.

Investigators were working with the company on Monday to find out how the pornographic video got onto the billboard, according to Auburn Hills police Lt. Ryan Gagnon.

Charges of promoting pornography and promoting pornography for minors could be filed in connection with the incident. Anyone convicted could face penalties of up to 90 days in jail and a $500 fine, police said.

Calls seeking additional comment from Gagnon and a rep for Triple Properties were not immediately returned on Monday.

No crashes were reported on the freeway near where the video played, Gagnon told the Detroit Free Press. But it was certainly a “huge distraction and obviously obscene and inappropriate,” Gagnon told the newspaper.

“It was dark out, so the screen was glowing really bright,” he said.