Description

Seat Heating Description
The heated seat elements for each seat are supplied power from a seat heat module located on the underside of the seat frame. The seat heat module provides consistent temperature control of the seat heater elements. A negative temperature coefficient variable resistor is located in the seat cushion heater element. The resistor changes its resistance as the seat cushion temperature increases or decreases. The resistance is monitored by electronics within the seat heat module, which raises or lowers the power supplied to the elements and controls the element temperature between 26 and 36°C (79 and 97°F)

The heated seat elements are operated by a latching seat heater switch for each seat located in the center console between the two rear window switches The heated seats only operate when the ignition switch is in position II.

Circuit Supply
A feed from the battery positive terminal is connected on an R wire to the engine compartment fusebox where it passes through fusible links 1, 5, 7 and 8. Fusible links 1 and 5 and 1 and 7 are connected in series.

A feed from fusible links 1 and 7 is connected to the contacts of the auxiliary circuits relay

A feed from fusible links 1 and 5 is connected on an NG wire to connector C0255-5/C0751-1 interface. From connector C0751-1 the feed continues on an NP wire to the coil and contacts of the LH power seat relay. The earth path from the relay coil is connected on an OP wire to the BCU pin C0663-3, via header C0724.

A second feed from fusible links 1 and 5 is connected on an NP wire to the coil and contacts of the RH power seat relay. The earth path from the relay coil is connected on an OP wire to the BCU pin C0663-3, via header C0724.

The BCU completes the earth path when ignition I or II or driver's door open is sensed.

A feed from fusible link 8 is connected on an NW wire to the passenger compartment fusebox and from the fusebox to the ignition switch on an N wire.

Ignition Switch Supply
With the ignition switch in position I or II the feed from fusible link 8 passes through the ignition switch to the passenger compartment fusebox on an LGW wire.

The feed continues through fuse 26 in the passenger compartment fusebox and is connected from the fusebox on an LG wire to the coil of the auxiliary circuits relay in the engine compartment fusebox. This feed energises the relay coil, closing the relay contacts. The relay coil is earthed on a B wire, via header C0286 LHD/C0288 RHD, to earth header C0018.