Windshield Heater

The windshield heater comprises 2 heater elements, LH and RH, bonded between the glass laminations. The system is switched on by pressing the momentary switch located on the control panel. When selected, the ATC module transmits a heating request on the high speed CAN bus to the CJB. On receipt of the message, the CJB energizes the windshield heater relay located in the BJB by providing a ground path for the relay coil. The energized relay provides a battery feed to both heater elements. After a period of 4 minutes the ATC module removes the request for windshield heating. The CJB then powers down the windshield heater by removing the ground path for the relay coil.

The ATC module will only request windshield heater operation if the engine is running. An engine status signal is provided to the ATC module by the ECM over the high speed CAN bus.