Electrical rl
SECTION CONTENTS
Sub-Section 15.4 Driver Ergonomics
Sub-Section Title SRO Page
15.4 ............. Driver Ergonomics .............................................................. 15.4- 1
15.4.1 ............ System Description .............................................................. 7 5.4- 1
15.4.1.1 .......... Entry/ExitMode ................................................................ 15.4-1
15.4.1.2 .......... Driving Position Set ............................................................. 15.41
15.4.1.3 .......... PassengerSeatSet ............................................................... 15.4-1
15.4.1.5 .......... Reverse Mirror Dip .............................................................. 15.4-3
15.4.2 ............ System Components ............................................................. 15.4-3
15.4.2.1 .......... Seats - Driver and Passenger ...................................................... 7 5.4-3
15.4.2.3
.......... Seat Lumbar Pump .............................................................. 15.4-3
15.4.1.4
.......... RemoteRecall .................................................................. 15.43
15.4.2.2 .......... SeatMOtors .................................................................... 15.43
15.4.2.4 .......... Seat
Heaters and Thermostats ..................................................... 15.4-3
15.4.2.5 .......... Seatswitch Pack ................................................................ 75.45
15.4.3 ............ Seat Control Module ............................................................. 15.45
15.4.3.1 .......... Seat Control Module Connector Pins ............................................... 15.4-6
15.4.4.1 .......... Column Motors ................................................................. 75.48
15.4.4.3 .......... Driver / Passenger Rear View Mirror Motors ......................................... 15.4-9
15.4.4 ............ Steering Column /Mirror ......................................................... 75.48
15.4.4.2 .......... Column Joystick Switch .......................................................... 15.48
15.4.4.4 .......... Mirror joystick .................................................................. 15.49
15.4.5 ............ Column/Mirror Control Module ................................................. 15.4-10
15.4.6 ............ Non-Memory and Manual Applications ........................................... 15.4-12
15.4.6.1 .......... Non-Memory ................................................................. 15.4-12
15.4.6.2 .......... Manualseats .................................................................. 15.4-72
15.4.6.3 .......... Manual Column ............................................................... 15.4-12
15.4.7 ............ Symptom FlowChafls .......................................................... 15.4-13
15.4.8
............ Diagnostic Sub-routines ........................................................ 15.4-17
15.4.9.16 ......... Key to Schematic Diagrams ...................................................... 15.4-35
15.4.9 ............ Pin-Point Tests ................................................................. 15.4-19
15.4.10
.......... Electrochromatic Rear View Mirror ................................................ 15.4-36
15.4.10.1 ......... Description ................................................................... 15.4-36
15.4.10.2 ......... Test Procedure ................................................................. 15.436
X300 EDM V Issue 1 August 1994
15.4 DRIVER ERGONOMICS
15.4.1 System Description
Adjustment of the seats, steering column and exterior rear view mirrors position is effected by means of control
switches. The switches maintain the adjustment facility while depressed, movement ceasing when the switch is re- leased.
Manual adjustment can be achieved either with the ignition key in place or with the driver‘s door open, or having been
closed within the last
30 seconds.
The system offers the following facilities:
Entry
/ Exit mode; an automatic seat /column position setting for ease of driver entry into / exit from the vehicle.
Driving position set; automatic recall of up to three preferred settings.
Passenger seat set; automatic recall of up to three preferred settings.
Remote recall; automatic recall of up to two memory positions from
a remote transmitter (in key fob).
Reverse mirror dip; automatic adjustment of passenger rear view mirror when reversing.
U: Vehicles intended for the Japanese market are fitted with an additional ‘fold away’ mirror function. This func- tion allows mirrors to fold flat against the car when parking in enclosed areas.
15.4.1.1 Entry/ Exit Mode
Entry / Exit mode is designed to give easier vehicle entry and exit for the driver. The facility is selected by positioning
the mode switch, located on the LH side of the column cowl, to ‘auto’ which designates the current seat / column posi- tion, ie driving positions, as the memorized position. On removal of ignition key or opening of driver‘s door, with igni- tion key still in place, the driver’s seat will move to the rear (current position allowing) and the column will adopt ‘tilt
away’ mode automatically creating additional space for driver exit
/ entry. Insertion of key in ignition or closure of
driver‘s door (with ignition key in place) returns seat / column positions to the memorized (previous) position.
Operation of eitherthe brake pedal or
seat/column manual controls during entry/exit mode execution will abort posi- tional adjustments. Setting the mode switch to OFF disables operation of entry / exit mode.
15.4.1.2 Driving Position Set
Setting of seat, column and external rear view mirrors to preferred driving position is available using the memory but- tons located on the drivers door switch pack. With the ignition key in place enter settings to be memorized as follows:
Adjust seat, column and mirrors to desired positions.
Press the ’memory’ button
so that it becomes illuminated.
Press button
1,2 or 3 to store configuration within four seconds of memory button operation. Memory light will extin- guish and a chime will sound, indicating procedure complete.
The above procedure may be repeated two more times until each button
(1,2 & 3) has a preferred position stored in
memory, accommodating different driver settings. Operation of any push-button (1,2 or 3) will re-position seat col-
umn and mirrors to the stored settings.
Memory recall will operate under the following conditions:
. Ignition key in and gear selector in park.
8 Ignition key in and handbrake on.
8 Ignition key out and driver’s door open (or having been closed within the last 30 seconds).
Re
-setting the preferred position on any setting button automatically erases previously stored information. Memory
information is not erased if power supply to the seat and column / mirror control modules is lost (e.g. battery discon- nected).
15.4.1.3 Passenger Seat Set
The procedure for setting and recalling a preferred passenger seat position is identical to that for a driving position.
Memory recall will only operate with ignition key in auxiliary position or passenger door open, or having been closed
within the last
30 seconds.
X300 EDM 15.4 - 1 Issue 1 August 1994
15.4.1.4 Remote Recall
Remote activation of memory positions 1 and 2 can be achieved using the key fob transmitters (one per set of keys).
lfthe vehicle is unlocked using the remote transmitter the stored driving position will be adopted automatically. If the
vehicle is unlocked using the remote transmitter and an exit position is already set the corresponding entry position
will be adopted until the ignition key is inserted, the stored driving position will then be restored. 0 ~
15.4.1.5
Reverse Mirror Dip
On selection of reverse gear and operation of the mirror toggle switch downwards, the passenger side rear view mirror
will automatically tilt downwards to assist reverse parking. Upward adjustment disables reverse dip, a further down- ward adjustment when still in reverse gear reinstates reverse dip. The mirror will return to normal position when any
other gear position is selected.
15.4.2 SYSTEM COMPONENTS
15.4.2.1 Seats
- Driver and Passenger
The driver and passenger seat adjustment systems comprises the following components:
o Fore / aft motor
o Front raise / lower motor
o Rear raise / lower motor
0 Squab recline motor
0 Headrest motor
0 Lumbarpump
0 Squab heater
0 Inner cushion heater
0 Outer cushion heater
0 Heater thermostat
0 Switch pack
o Seat Control Module (SCM)
o Wiring harness
15.4.2.2 Motors
The five seat position adjustment motors are located below the seat cushions (horizontal and vertical adjustment) and
behind the squab (recline and headrest adjustment). Each motor unit incorporates a potentiometer which provides
directional movement position control via feedbackvoltage variations to the SCM. Positional variations are activated
by the SCM in response to signals from switches mounted on the seat switch pack.
15.4.2.3 Lumbar Pump
The lumbar pump, located behind the seat squab allows adjustment of seat rigidity by increasing/decreasing air pres- sure in the lumbar pad. The pump motor is controlled from a switch on theseat switch pack and governed by an in-line
pressure switch.
A solenoid valve is used to regulate air flow to the lumbar pad.
15.4.2.4 Heaters and Thermostats
The two cushion heaters and squab heater are regulated by a single in-line thermostat and operated by a switch
mounted on thecenter console switch pack. Operation of this switch causesthe Body Processor Unit (BPU) to energize a timed input to SCM (for 11 minute f 1) which in turn causes SCM to energize the heater supply. The supply will
remain on until timed out, although the heater circuit will be broken by the thermostat if the set temperature is ex- ceeded.
Note: Heatingcan only occur when the ignition switch is position I1 and the ambient temperature is belowthe thermo- stat pre-set value of 26°C.
X300 EDM 15.4 - 3 Issue 1 August 1994
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15.4.6 NON-MEMORY AND MANUAL APPLICATIONS
15.4.6.1
Non-Memory
Seats, column and mirrors may be supplied without memoryfacilities on certain vehicles. In this case, adjustment of
each application is still controlled in the same way but the memory facility is disabled and the memory switch pack
not fitted.
15.4.6.2 Manual Seats
Manual seats are adjustable vertically and horizontally, vertical adjustment being motorized but horizontal adjustment
manually effected. The seats have heated cushions and squab, but are not operated by an electronic control module.
Control is effected using three relays, two for vertical adjustment and one for heating.
Vertical adjustment is requested
by operation of a switch located on the left-hand side of the seat front which completes
the electrical supply to either the raise or lower relay as required. When either relay is energized a change of contact
state connects one side of the motor to
+12V and the other side to ground. Reverse operation reverses supply and
ground connection.
Heating is still controlled by a timed output from the BPU. Operation of a switch located on the
center console indicates
to BPU that heating is required. Battery voltage is then applied to the heater relay for 11 minutes. The relay contact
completes the heater circuit, providing seat heating (and illuminating the switch surround) until the timer expires, or
optimum seat temperature is achieved. Operation of the heater switch before 'time-out' is achieved cancels the heat- ing request. Operation of the heater switch after 'time-out' has been achieved re-starts the heating cycle.
15.4.6.3 Manual Column
Manual column adjustment in the two planes is achieved by purely mechanical means, release catches allowing col-
umn movement within a fixed locking mechanism.
Rear view mirror position adjustments
1. Locate mirror select switch on driver's door switch pack and select driver's side mirror, ie
rotate switch towards the door.
2. Locate rear view mirror joystick switch on driver's door pack.
Operate the switch to give left
/ right and up / down movement. Does the mirror respond
in the correct manner?
3. Yes: Proceed to step 4 or 5.
No:
Japanese market vehicles only
Operate the switch to action 'fold away mode'. Does mirror respond in the correct manner
in each case?
Yes: Proceed to step
5.
No:
All markets
Operate mirror select switch to opposite position and repeat steps
1 to 4 for passenger side
mirror.
With ignition switched to auxiliary, select reverse gear and operate mirror joy
-stick
downwards. Does passenger side mirror dip automatically?
Yes: Proceed to step
7.
No:
Remove key from ignition, close driver's door and allow 30 seconds to elapse. Repeat
steps
1 - 6 and check that adjustment cannot be made.
Test complete; proceed to Memory Position Set.
Abort
test and refer to Diagnostic Sub
-Routines.
4.
Abort test and refer to Diagnostic Sub-Routines.
5.
6.
Abort test and refer to Diagnostic Sub-Routines.
7.
8.
Memory set position - drivefs side
1.
2.
3.
4.
5.
6.
7.
8.
Position the entry / exit switch, located on the LH side of the steering column, to off and
insert the key in the ignition.
Operate switches to position column, mirrors and seats to preferred positions.
Select 'memory' on the driver's door switch pack. Check that switch illuminates.
Depress desired memory button,
1,2 or 3, on door switch pack within 4 seconds of
memory select. Check that a chime sounds to confirm memory storage.
Operate the switches
so that memorized positions are changed. Depress relevant memory
option button,
1,2 or 3 and check that all positional settings are restored as memorized.
Remove key from ignition, close all doors and allow
30 seconds to elapse. Repeat steps 1
to 4 and check that adjustment cannot be made.
Readjust settings so that memorized positions are changed, leave the vehicle and operate
remote memory recall by locking and unlocking using the remote transmitter. Use both
transmitters to check both memory positions. Check all positional settings are restored as
memorized.
Yes: Proceed to step
8.
No:
Test complete. Abort
test and refer to Diagnostic Sub
-Routines.
X300 EDM Issue 1 August 1994 15.4 - 14
n E I ectr ical
2A. Seat movement motors (memory seats)
a.
b.
Check motor operation is not obstructed, and that mechanical linkage is not damaged
or disconnected.
Examine wiring harness, checking continuity between SCM Connector
A1 and motor
unit connector pins as follows:
SCM Motor Function Unit Pin
Pin 8 Seat forward 1
Pin
7 Seat rearward 3
Pin 5 Seat rear raise 1
Pin
6 Seat rear lower 3
Pin 3 Seat front raise 1
Pin
4 Seat front lower 3
Check resistance between motor pins 1 and 3, a value of approximately 2S2 should be
indicated.
Check motor position potentiometer as described in test
4.
C.
d.
28. Seat movement motor (manual seats)
a.
b.
C.
d.
Check motor operation is not obstructed, and that mechanical linkage is not damaged
or disconnected.
Check continuity from motor connector pins (1
& 3) to each relay contact connector
(pin
3, raise relay, pin 8, lower relay) respectively.
Check power supply
(+12V) from LH 'A' post base fuse box, fuse F6, to seat switch
connector pin
9.
Check power supply (+12V) from RH 'A' post base fuse box, fuse F3, to pin 5, raise relay
connector and pin 10, lower relay connector.
Check continuity from switch pack connector pin
4 to raise relay connector pin 5 and
from switch pack connector pin 5 to lower relay connector pin
6
Check continuity to ground from raise relay connector pins 2 and 4 and lower relay
connector pins
7 and 9
e.
f.
3. Seat squab 1 headrest motors
a.
b.
Check motor operation is not obstructed, and that mechanical linkage is not damaged
or disconnected.
Examine wiring harness, checking continuity between SCM Connector
A1 and motor
unit connector pins as follows:
SCM Motor Pin
Pin 1 Squab recline 1 incline +ve 3
Pin 2 Squab recline 1 incline -ve 1
Pin 11 Headrest raise
1 lower +ve 1
Pin 12 Headrest raise
1 lower -ve 3
Check resistance between motor pins 1 and 3; a value of approximately 28 should be
indicated.
Check motor position potentiometers as described in step
4.
C.
d.
Issue 1 August 1994 15.4 - 20 X300 EDM
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6A. Heating (powered seats)
a. Examine harness wiring, checking continuity between SCM connector AI pins 9 and
10. A resistance value of 1.5-3.252 should be recorded indicating all heating
elements intact and thermostat closed.
Check continuity from BPU black 48
-way connector B, pin 38 to center console seat
heater switch module connector pin
5. Operate switch and check continuity from BPU
black 48
-way connector B pin 38 to ground.
Check continuity between cushion heater module and squab heater module pins;
resistance values of
1.0-2.052 and 0.51.252 respectively should be achieved.
Check continuity from SCM connector B2 pin
2, through console switch LED to ground;
a resistance value of 0 - 0.552 should be recorded.
b.
C.
d.
1
J86 - 1872
Fig. 1 Memory Seat Heaters
e
0
0
0
68. Heating (manual seats)
0 a. Examine harness wiring, checking fuse F9 in RH 'A' post base fuse box.
Ensure continuity between heater relay connector pin 85 and BPU yellow 48
-way
connector pin 23. Measure resistance from heater relay pin 87 and console switch
connector pin 10.
Check continuity from BPU black 48
-way connector B pin 38 to center console seat
heater switch module connector pin
4. Operate switch and check continuity from
BPU black 48
-way connector pin 38 to ground.
Check for
+12V supply at seat heater relay connector pins 30 and 86.
Check continuity between cushion heater module and squab module pins; resistance
values
of 1.0-2.052 and 0.5-1.252 respectively should be achieved. Ensure secure
ground connection from squab connector pin 3.
Check continuity from console switch connector pin
10 through console switch LED to
ground;
a resistance value of 0-0.5Q should be recorded.
b.
C.
d.
e.
I' T
I 19 15 16
17 OK
J86 - 1873
Fig. 1 Manual Seat Heaters
Issue 1 August 1994 X300 EDM 15.4 - 25