Defender is now fitted with heated front seats, which operate when the ignition switch is turned to the 'ignition' position. The seat heat switches are latching switches, and are located on the fascia console. Each switch also contains a tell-tale LED. Both seat heater elements contain a thermostatically controlled switch. When the element temperature reaches 37 ± 3 °C (98 ± 3 °F), the thermostat cuts the supply to the heater elements for that seat. As the temperature of the heater elements falls to 28 ± 3 °C (82 ± 3 °F), the thermostat closes causing the elements to heat up again.
Operation
Power Distribution
Feed from the positive battery terminal (C0192) is supplied to fusible link 1 and fusible link 5 of the under seat fuse box (C0632) on an N wire. Fusible link 1 is connected in series with fusible link 3, which is also located in the under seat fuse box. Fusible link 3 (C0571) provides a constant battery feed to the ignition relay (C0218) on an NR wire.
Fusible link 5 (C0570) provides a constant battery feed to the ignition switch (C1043 on LHD, C0028 on RHD) on an NW wire. When the ignition switch is turned to the 'ignition' position, current flows across the switch (C1732 on LHD, C0094 on RHD) to fuse 15 of the passenger compartment fuse box (C0580) on a W wire. Fuse 15 (C0580) provides an ignition feed to the ignition relay coil (C0218) on an LGP wire. The relay coil (C0218) is earthed on a B wire. The energised ignition relay (C0218) provides a feed to fuse 33 of the passenger compartment fuse box (C0595) on an NS wire.
RH Seat
Fuse 33 of the passenger compartment fuse box (C0595) provides a feed to the RH seat heat switch (C0249) on an LGW wire. When the seat heat switch is depressed, current flows across the switch contacts (C0249) to the seat heater element (C0237) on a UK then U wire. The heater element (C0237) is earthed on a B wire.
LH Seat
Fuse 33 of the passenger compartment fuse box (C0595) provides a feed to the LH seat heat switch (C0250) on an LGW wire. When the seat heat switch is depressed, current flows across the switch contacts (C0250) to the seat heater element (C0237) on a US then U wire. The heater element (C0237) is earthed on a B wire.
NOTE: The seat heater elements have the same connector number as they utilise the same harness.