A vehicular vision system includes a camera including an image sensor, a control including a microcontroller, and a serial data interface. The camera has a field of view exterior of a vehicle. A video output is configured for transmitting a stream of video captured by the image sensor. The microcontroller is operatively connected to the image sensor. The serial data interface permits the microcontroller to communicate with at least one electronic device in the vehicle. A resistor having a selected impedance is connected in series with a switch. The resistor and the switch connect a video plus electrical conduit and a video minus electrical conduit. The switch is openable by the microcontroller to deactivate the video output into a high impedance state and is closable to activate the video output. The microcontroller is configured to comply with selected messages received through the serial data interface by opening the switch.