The heated rear window (HRW) is operated by a latching switch mounted on the dash panel. When the switch is set to the "On" position, the instrument panel warning lamp will illuminate to indicate the HRW is operating. The HRW only operates when the ignition switch is turned to position "II".
Operation
Feed from the positive battery terminal is connected to the engine compartment fuse box (C632-1) by a brown wire. Current passes through fusible link 2 and fusible link 4 of the engine compartment fuse box, which are connected in parallel. Fusible link 2 (C907-2) is connected to the ignition switch (C028-1) by a brown wire.
With the ignition switch in position "II" (C094-1), current flows to the HRW switch (C381-2) on a white wire. The switch controls the HRW relay coil. When the switch is depressed, current flows from the switch (C381 -4) to the relay coil (C044-85) on a white/green wire. Current flows across the coil and is earthed (C044-86) by a black wire via the earth header joint(C287-2).
With the relay coil energised, battery feed via fusible link 4 (C906-1) is able to flow across the HRW relay main terminals (C044-87 & C044-30). The energised relay now supplies a feed to fuse 8 of the passenger compartment fuse box (C580-15) on a brown/white wire.
Fuse 8 of the passenger compartment fuse box (C580-16) supplies current to the HRW element (C382-1) on a brown/white wire, and the HRW warning lamp (C929-1), also on a white/brown wire. The warning lamp and heater element are connected in parallel.