The solo crash happened near the corner of Second Avenue and School Street around 7:30 a.m.
Gaumer said a car southbound on Second drifted and hit the concrete base of a sign at the H.H. Dorje Chang Buddha III Cultural and Art Museum, 170 E. School St.
He said the driver, a 27-year-old Covina man, wasn’t injured. A helicopter transported the driver’s son to a hospital.