Automotive manufacturers commonly employ a variety of thin conductive materials, including electrical heaters, in the manufacture of vehicles. Such electrical heaters may take the form of rear window defrosters, windshield wiper park position heaters, mirror heaters, and sensor heaters, the latter used, for example, for sensor windows of autonomous vehicle control systems. Such heaters may be constructed by printing a conductive material directly on glass by, for example, using a silver-impregnated ink. The ink is then cured on the glass in an oven.
The printed heater conductors must be connected to the automotive electrical system, which is typically accomplished through a wiring harness conductor. In the simplest approach, a metal terminal is soldered onto the printed conductor. The metal terminal may be attached to a releasable electrical connector that communicates with a flexible wire of the automotive wiring harness and conducts current from the automotive electrical system through the printed heater material to heat the glass surface by resistive heating. However, the process of soldering a metal terminal to the printed conductor requires high temperatures, which can cause microcracks in the glass surface supporting the printed conductor and later lead to glass failure.
Therefore, there is a continued need for making an electrical connection to a printed conductor on a glass surface, such as a printed heater material, without soldering a metal terminal directly to the printed conductor.