Abstract: A system for electrically heating a volume of windshield cleaning fluid in a motor vehicle includes a metallic vessel connected between a windshield fluid reservoir and a nozzle for spraying the windshield with the fluid. The vessel has a metal heater wall heated by PTC thermistors thereon and provided with a plurality of metal heat exchange pins extending into an internal chamber in the vessel through which the fluid flows to be heated. A control circuit is provided and includes an electronic timer circuit for controlling the length of time the thermistors are energized to heat the fluid in accordance with the prevailing ambient temperature, an engine speed sensor including a pulse stretching circuit for preventing energization of the thermistors if the engine of the vehicle is not running, and a differential input circuit for simplifying the attachment of the system to a standard windshield cleaning fluid pump.