Chicago’s top cop is calling for an internal investigation — on himself — after officers found him slumped over inside his parked car early Thursday.

Windy City Superintendent Eddie Johnson, 59, pulled over and parked his car near his home around 12:30 a.m. Thursday because he felt lightheaded, police spokesman Anthony Guglielmi said in a statement.

Officers responding to a 911 call about a person asleep at a stop sign found the superintendent, but “did not observe any signs of impairment,” and Johnson drove himself home.

Earlier in the week, Johnson went to the doctor about a change in his blood pressure medication and by Wednesday reported that he felt exhausted, officials said.

He went to the doctor again Thursday for his blood pressure.

Alcohol didn’t play a role in Johnson feeling ill and pulling over, Guglielmi said.

Johnson called for a probe into the incident because “whether you are Police Officer or a Superintendent, all Officers ought to be held to the highest standard.”

Johnson was hospitalized in June for a blood clot and received a kidney transplant from his son about two years ago.

Additional reporting by Gabrielle Fonrouge