Heated Glass Element: Description and Operation

The DEFOGGERS operate when voltage is applied to the DEFOGGER wires. The heat generated by current passing through these wires removes fog or ice from the glass.

When the Rear Defogger Button on the ECC CONTROL HEAD is pressed the ECC CONTROL HEAD signals the ECC PROGRAMMER to turn on the DEFOGGERS if the engine is running and engine RPM is greater than 200 RPM. The ECC CONTROL HEAD signals the ECC PROGRAMMER through circuit 720 (data line) to turn the DEFOGGERS on and off. The ECC CONTROL HEAD synchronizes the signals to the ECC PROGRAMMER through circuit 713 (clock). Circuit 720 and 713 are also used to control all other climate control functions by the ECC CONTROL HEAD.

Timing of the DEFOGGER cycles is done by the ECC CONTROL HEAD. The first cycle is 10 minutes. Other cycles are 5 minutes during the same ignition cycle.

The ECC PROGRAMMER turns on the DEFOGGERS by grounding the DEFOGGER RELAY coil. The relay energizes and voltage is applied to the DEFOGGERS. The ECC PROGRAMMER turns the DEFOGGERS off by removing ground from the DEFOGGER RELAY coil.

Whenever the DEFOGGERS are on the vacuum fluorescent (VF) defogger indicator is turned on in the ECC CONTROL HEAD.