SWITCH, Defogger

DESCRIPTION

The switch for the rear window defogger (EBL) system is integral to the mode control knob (4) located in the A/C-heater control (1). When the rear window defogger switch is pressed on, the amber indicator in the control knob illuminates and a request signal is sent to the Totally Integrated Power Module (TIPM) to operate the EBL system.

When the EBL high side driver in the TIPM is energized, current is directed to the rear defogger grid lines to heat the glass to help clear the surface of fog or frost.

OPERATION

An amber indicator illuminates when the rear window defogger switch is activated. When activated, the Cabin Compartment Node (CCN) sends a request signal to the Totally Integrated Power Module (TIPM) to energize the internal Electric Back Light (EBL) (rear window defogger) high side driver to provide battery current to the rear window defogger grid lines.

The EBL system will be automatically turned off after an initial programmed time interval of about 10 minutes as long as the ignition switch is in RUN. After the initial time interval has expired, if the rear window defogger switch is pressed to ON again during the same ignition cycle, the EBL system will automatically turn off after about 5 minutes. The EBL system will also turn off if the ignition switch is turned to any position other than RUN or by manually pressing the rear window defogger switch a second time.

The rear window defogger switch is diagnosed using a scan tool (Refer to 28 - DTC-Based Diagnostics/NODE, Cabin Compartment (CCN) - Diagnosis and Testing).

The rear window defogger switch and indicator lamp cannot be adjusted or repaired and the A/C-heater control must be replaced if found inoperative or damaged (Refer to 24 - Heating and Air Conditioning/Controls/CONTROL, A/C and Heater - Removal) .