Seats: Description and Operation
Seats
Front Seats
General
Two seat options are available:
^ Electric seat - finished in cloth
^ Contour seat - finished in leather.
The electric and contour seats are fitted with a manually adjustable folding armrest on the inboard side of the seat. Heated seats and a memory recall function are also available on higher specification vehicles.
Electric Seats
The electric seats are adjusted in the following axis by switches fitted in the seat side trim casing:
^ Forward/backward adjustment
^ Seat cushion height
^ Seat cushion angle - driver's seat only
^ Backrest angle
^ Lumbar support - horizontal and vertical.
The seat has the following manual adjustments:
^ Head restraint angle
^ Head restraint height.
Contour Seats
In addition to the electric seat adjustments the Contour seat has the following additional functions:
^ Electrical adjustment of the upper backrest
^ Electrical adjustment of the head restraint
^ Seat angle adjustment - driver and passenger seats
^ Seat heating.
Head Restraint Adjustment
Memory Function
The memory function is available as an option on higher specification vehicles. Controlled by the GEM (generic electronic module), the memory function stores and recalls the position of the drivers seat, the steering column and the exterior mirrors. Memory buttons located on the outboard edge of the seat trim casing allow the driver to store up to three memory positions.
The memory recall functions are:
^ Forward/backward adjustment
^ Seat height
^ Seat angle - driver's side only
^ Backrest angle
^ External mirror adjustment - left and right
^ Steering column forward/backward adjustment.
To operate the memory function:
^ Turn the vehicle ignition switch to position II (ignition on)
^ Set the seat, steering wheel and exterior mirrors to the required position
^ Press and hold the 'M' memory store button. The LED (light emitting diode) located on the button will now illuminate
^ While pressing the 'M' button, simultaneously press one of the three memory recall buttons
^ If the store request has been successful, the LED (light emitting diode) will extinguish.
The seat, steering column, and exterior mirrors will move to the stored position whenever the relevant memory recall button in pressed.
NOTE: Seat, steering column and exterior mirror movement will be halted if any seat adjustment switch (including memory buttons) or the steering column adjustment switch is moved or pressed. To re-start movement of these, the relevant seat memory button will need to be pressed again.
Rear seats
The rear bench seats are designed to fold forward to increase the rear load space. A 60:40 split gives the owner increased flexibility when loading the vehicle with large objects. All rear seats are equipped with three point seat belts and adjustable head restraints. High specification vehicles are also fitted with seat cushion heaters in both outboard seats.
Memory Control Module
Two memory control modules are available; standard and Contour. The memory control module is configured to move the seat through 4 (standard) or 6 (Contour) axis and can also be configured for adjusting the steering column.
Standard
The standard memory control module is capable of controlling four seat motors with hall sensors and two steering column motors. The switches for the controls are located in the module and shaped to give an indication of their corresponding function.
The control functions are:
^ Forward/backward movement
^ Seat height
^ Recline
^ Tilt.
The steering column switches are connected to the unit via a 4 pin connector. The functions are:
^ Up/down
^ Forward/backward.
Contour
The Contour memory control module is fitted with two additional motors to control the seat in the following axis:
^ Upper seat backrest adjustment
^ Head restraint adjustment.
Seat Power Relay
The seat power relay is located in the CJB (central junction box) and is provided a constant battery feed and an ignition on feed. Operation of the relay is controlled by the GEM (generic electronic module). When energised, the relay provides a feed to the memory control module via fuse 20P, and the seat switch pack via fuse 21P.
Seat Switch Pack
The seat switch pack is mounted on the seat valance and provides movement in the following axis:
^ Seat forward/backward adjust
^ Seat height adjustment
^ Seat angle adjustment
^ Backrest angle adjustment
^ Backrest head adjustment
^ Head restraint height adjustment.
Manual adjustment of the seat position can be carried out at any time, having priority over memory recall. The control module sequences the order of adjustment.
Seat Forward/Backward Motor
The seat forward/backward motor is a permanent magnet motor coupled to a rack and pinion assembly. Should the motor seize or stick for 6 seconds or more, an internal thermal cut-out switch will trip to remove voltage from the motor. Reset time for the switch is 35 seconds. Two pins within the seat switch pack control the seat forward/backward motor. Both pins are normally ground. Operating the backward switch applies voltage to that pin while the other pin remains ground. Operating the forward switch reverses power and ground to the motor allowing the motor to run in the opposite direction.
Seat Cushion Front Up/Down Motor
The seat cushion front up/down motor is a permanent magnet motor coupled to a rack and pinion assembly. Should the motor seize or stick for 6 seconds or more an internal thermal cut out switch will trip to remove voltage from the motor. Reset time for the switch is 35 seconds. Two pins within the seat switch pack control the seat cushion front up/down motor. Both pins are connected to ground. Operating the up switch applies voltage to that pin while the other pin remains connected to ground. Operating the down switch reverses power and ground to the motor allowing the motor to run in the opposite direction.
Seat Cushion Rear Up/Down Motor
The seat cushion rear up/down motor is a permanent magnet motor coupled to a rack and pinion assembly. Should the motor seize or stick for 6 seconds or more, an internal thermal cut out switch will trip to remove voltage from the motor. Reset time for the switch is 35 seconds. Two pins within the seat switch pack control the seat cushion rear up/down motor. Both pins are connected to ground. Operating the up switch applies voltage to that pin while the other pin remains connected to ground. Operating the down switch reverses power and ground to the motor allowing the motor to run in the opposite direction.
Seat Backrest Forward/Backward Motor
The backrest forward/backward motor is a permanent magnet motor coupled to a rotary rack and pinion assembly. Should the motor seize or stick for 6 seconds or more, an internal thermal cut out switch will trip to remove voltage from the motor. Reset time for the switch is 35 seconds. Two pins within the seat switch pack control the backrest fore/aft motor. Both pins are connected to ground. Operating the fore switch applies voltage to that pin while the other pin remains connected to ground. Operating the aft switch reverses power and ground to the motor allowing the motor to run in the opposite direction
Lumbar Pump
The lumbar pump inflates a bladder in the backrest which provides extra support for the seat occupant. With no load on the seat it takes approximately 10 seconds to completely inflate the bladder. With a load of 25 kg (55 lb) it takes approximately 15 seconds to inflate the bladder. A pressure cut off switch in the system will operate at 0.12 to 1.93 bar (1.8 to 28 lbf.in2). The lumbar bladder can be replaced independently of the pump. The components are not serviceable.
Manual Adjustment of Drive Motors
The seats can be manually adjusted at any time. Positioning is interrupted if manual adjustment is required during automatic adjustment (memory recall). The manual adjustment is not effective before the switch is operated again.
Due to the sequential activation of the drive motors, the switch requests are prioritised in the following order:
^ Forward/backward adjustment
^ Backrest
^ Height
^ Angle
^ Head restraint
^ Backrest head
^ Steering column angle
^ Steering column forward/backward adjustment.
Heated Seats
Heating elements are fitted in the cushion and backrest of both front seats and both outboard rear passenger seats. Operation of the front seats is controlled via switches mounted in the ATC (automatic temperature control) module. The switches for the heated rear seats are located in the rear of the center console.
Front Heated Seat Controls
Two push-button switches are mounted in the ATC (automatic temperature control) module panel. Each switch has two integral LED (light emitting diode) to display the level of heating selected.
Both LED (light emitting diode) OFF - No heating
Two LED (light emitting diode) ON - High level heating (44 degrees C)
One LED (light emitting diode) ON - Low level heating (39 degrees C)
When a seat heater switch is pressed, the ATC (automatic temperature control) module supplies an ignition feed to the relevant front seat heater unit. Current flows to the seat heater elements and the NTC (negative temperature coefficient) temperature sensor.
The ATC (automatic temperature control) module regulates the level of seat heating if its internal temperature starts to rise above 85 degrees C. Initially the level of seat heating is reduced to 88% then progressively reduced until, if the internal temperature exceeds 95 degrees C, the system shuts-down.
Rear Heated Seat Controls
Two push-button heated seat switches are mounted in a pack located in the rear of the center console. Each switch has two integral LED (light emitting diode) to display the level of heating selected.
Both LED (light emitting diode) OFF - No heating
Two LED (light emitting diode) ON - High level heating (44 degrees C)
One LED (light emitting diode) ON - Low level heating (39 degrees C)
The rear seat heater switch pack also contain logic to control operation of the rear seat heaters. When a seat heater switch is pressed, the switch pack supplies an ignition feed to the relevant seat heater element and the NTC (negative temperature coefficient) temperature sensor.
The switch pack regulates the level of seat heating if its internal temperature starts to rise above 85 degrees C. Initially the level of seat heating is reduced to 88% then progressively reduced until, if the internal temperature exceeds 95 degrees C, the system shuts-down.
Seat Heater Temperature Sensor
Feedback of the seat temperature is via a NTC (negative temperature coefficient) sensor within the seat cushion. The resistance of this sensor changes with the temperature of the seat cushion allowing the ATC (automatic temperature control) module or rear seat heater switch pack to raise or lower the voltage to the seat heater elements to raise or lower their temperature.
An ignition feed is supplied to each sensor via the relevant seat heater switch.
Seat Heater Elements
The seat heater elements are located in the seat cushion and backrest. The cushion and backrest heater elements are wired in series. Total power consumption at 13.5 volts is approximately 115 Watts. The cushion heater element has an input feed from the temperature control unit or heater switch and an output to the backrest heater element, which outputs to ground.
Operation
CAUTION: The seat heaters consume considerable power from the battery. For this reason, they should only be operated while the engine is running.
When the seat heater switch is initially pressed high level heating is selected, pressing the switch a second time selects low level heating and pressing the switch a third time switches the heating off.
The seat heaters are thermostatically controlled and will operate intermittently to maintain a predetermined temperature. The indicator lights in the switches will remain illuminated until either the heaters are manually turned off, or the ignition switch is turned off.
When the seat heater switch is operated, power is supplied to the heater elements in the seat, causing the seat to heat up. The ATC (automatic temperature control) module (front seats) or seat switch pack (rear seats) senses seat temperature via the sensor in the cushion and regulates voltage to the seat heater elements to maintain a constant temperature.
The heater elements increase and then maintain the seat at a temperature of between 37 and 44 degrees C.
Fault Finding
In the self-test mode the switch indicates faults by displaying a flashing code.
The sequence to select test mode is:
^ Press the heating switch with the ignition off
^ With the switch depressed turn on the ignition switch to position II
^ Release the switch, this activates the self-test mode
^ After 10 seconds the flashing code is displayed.
The flashing code indicates the following faults
^ 1 Flash - Switch over temperature (T > 95 degrees C)
^ 2 Flashes - Short circuit and/or interruption in the sensor
^ 3 Flashes - Short circuit and/or interruption in the heating elements.
With the switch set to test mode, maximum heating is selected and both lamps are lit. If a fault is identified the heating is switched off and, after 10 seconds, the left LED (light emitting diode) switches off, this LED (light emitting diode) generates the flashing code. If no fault is detected the LED (light emitting diode) remains unlit.
To return to the test mode the switch is pressed twice and the sequence starts again. To cancel the test mode the ignition switch is turned off.