Heated Rear Window: Notes

WARNING: This page is about a different car, the 2004 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.

The heated rear window is controlled by the REM, PCM and the dual auto temp control (DATC) module. The heated rear window switch is incorporated into the DATC module. When the switch is pressed ON, the DATC module sends a message over the SCP network to the REM. The REM checks other messages for vehicle RPM from the PCM. If the RPM message is received, the REM grounds the heated rear window relay coil control circuit (which is hardwired to the REM). The ground signal closes the heated rear window relay which applies power to the heated rear window grid. Fault management of the heated rear window feature prevents the heated rear window from operating when an RPM or ignition switch invalid/missing data message is received. The heated rear window eliminates condensation on the rear window.