A vehicular windshield electronics module includes a housing configured to attach at an interior portion of a vehicle. The housing includes a front portion extending along a windshield of the vehicle and a rear portion extending along a roof of the vehicle. The housing accommodates a camera at the front portion of the housing. The camera generates heat within the housing. Electronic circuitry at the rear portion of the housing generates heat within the housing. An interior rearview mirror assembly includes a mirror head mounted at the housing and at least one electronic component generates heat within the mirror head. An electrically operable fan generates cooling air within the housing. Ducts are formed through the housing so that air flow may pass into and out from the housing. To dissipate heat, the air flow from the fan passes along the camera, along the electronic circuitry and along the mirror head.