Brakes
12.2 SYSTEM DESCRIPTION
The anti-lock braking system (ABS) and traction control system CTC) comprise the following components:
0 Hydraulic module: incorporating a pump, motor, low pressure accumulator, valve block, and either an ABS Con-
trol Module (ABS CM) or an ABS / TC Control Module (ABS / TC CM).
U!&: Within the hydraulic module are contained the electro-hydraulic inlet and outlet valves which regulate brake
system pressure.
o Four wheel speed sensors; hub end mounted.
0 Three warning indicators plus a Brake Warning Lamp and a Traction OFF / ON switch; fascia mounted.
0 Throttle valve flap positioning mechanism; mounted adjacent to the hydraulic module.
0 Various auxiliary inputs; providing information to ABS / TC CM.
0 Diagnostic IS0 communication BUS input / output link.
The solenoid operated hydraulic valves
are activated by signals, from the ABS /TC CM, which are generated using in-
formation received from the wheel speed sensors.
For vehicles without traction control thevalves operate on threecircuits, two front and one rear, as necessaryto prevent
wheel locking during braking. Brake pressure is modulated individually
at the front wheels and collectively at the rear.
Rear wheel control operates
a 'select low' principle such that locking in either wheel is sensed, and controlled brake
pressure is applied to both wheels.
Vehicles with traction control fitted have
all four wheels individually controlled allowing selective regulation of tractive
and braking force to each wheel as necessary when traction control is in operation.
The ABS
/ TC system as a whole is monitored constantly by the ABS / TC CM and is disabled (switched off until fault
is rectified) automatically when certain failures are identified. In the event of
a failure being detected the ABS and TC
MIL lamps, located on the instrument panel will illuminate. Full boosted brake operation and normal acceleration con- trol is available when ABS /TC is disabled. The system will be disabled when the following conditions occur:
0 Valve failure.
0 Sensor failure.
0 Main driver failure (internal ABS / TC CM fault).
0 Redundancy error (internal ABS / TC CM fault).
0 Over-voltage.
0 Pump motor failure.
0 Throttle valve actuator motor failure.
In the event
of under-voltage both ABS and TC will be disabled and the ABS andTC MIL lamps on the instrument panel
will illuminate.
U!&: The TC MIL lamp will only illuminate providing a voltage is still present at pin 15 'IGN FEED'
Throttle potentiometer failure will disable the TC function only and illuminate the TC MIL lamp.
The
moduleABS/TC CM is activated when ignition is ON, after an initiation period of approximately 1.7 seconds. After
this time delay the control module is ready to process signals provided from the various input sources and, using the
software defined algorithm, control the electrical and hydraulic circuits.
The inductive sensors attached to each of the four wheels provide speed signals to the ABS
/ TC CM. These signals are processed by ABS/TC CM giving comparison between individual wheel speeds, controlling braking or traction as
necessary and generating a pulse to drive the speedometer. Each sensor is monitored for open and short circuit failure,
causing disabling of ABS / TC on detection of a fault condition.
Issue 1 August 1994 2 X300 EDM
Climate Control Systems
System Differences
m:
Heater only vehicles do not have the following fitted:
This section applies generally to both air conditioning and heater systems. System specific descriptions, pro-
cedures, tests etc. are indicated.
0 Solar sensor
0 Clutch request and acknowledge circuitry.
0 Refrigerant pressure switch.
0 Control panel - deletion of air conditioning button.
6 cyl. engined vehicles do not have either the electrical load inhibit or the compressor lock sensor.
Heated Front Screen
(HFS) is optional on both air conditioning and heater panel versions.
14.2 COMPONENT DESCRIPTIONS
14.2.1 Control Panel
The control panel (Fig. 1) provides the operator interface with the climate control system.
The control panel communicates with the
A / CCM via a serial data communications link. During each data transfer
cycle the control panel states whether it is an air conditioning or heater version, thus enabling the A/ CCM to control
the system functions accordingly.
Tontrol panel operation is described in detail in the 'Climate Control Systems' section of the VSM.
-
Fig. 1 Control Panel (A / C with Heated front Screen)
J86 - I726
14.2.2 Control Panel Inputs /Outputs
Description I CableColor
I 1 I Output clock I Grey I
2 Output start Grey / Red
3 Input data
in Grey / Yellow
4 Output
data out Grey / Green
5 Output
ignition positive White / Red
6 Output auxiliary positive
White / Blue
7 Output
ground Black
8 Dimmer
Red
9 Dimmer override Red / Green
I 10 I Not connected I- I
I 11 I Not connected I- I
I 12 I Not connected l- I
X300 EDM 3 Issue 1 August 1994
Climate Control Systems
Actlon
Simultaneously hold FACE and FAN and switch the ignition
ON
14.4 CLIMATE CONTROL SYSTEM TEST
The control panel has a self-diagnosis feature, and is capable of displaying and deleting stored fault codes.
Climate control is an integrated system, therefore
it is recommended that the Portable Diagnostic Unit (PDU) is used
for fault diagnosis. The fault codes displayed with the control panel self-diagnosis feature are not as comprehensive
as those of the PDU. The PDU will display the relevant fault code, fault code description and information of the system
peripherals at the time the fault occurred.
Resu It
Control panel inputs for clock, start, data, ignition +ve and
auxiliary +ve are simultaneously examined and cause indi-
cator LED’s to illuminate on satisfactory line test.
14.4.1
System error information is stored in the A/ C CM up to a maximum of 5 faults. Should a fault occur there will be an
audible’beep‘and the message ‘Er’will be displayed on thecontrol panel LCD display for some 5 seconds after ignition
on. Please note that this will happen only once in any ignition switch cycle. The error source may be accessed by the
following procedure. A list and description of all accessible fault codes is provided on the following page.
Fault Code Extraction and Deletion Procedure
I Item Check LED
Ignition Defrost
Auxiliary Face
Clock Feet
/ face
Start input Foot
Data out Screen
/ foot
Dimmer override Recirc.
. Switch off the ignition.
Press and hold the ‘Auto’ and ‘Fresh / Recirc.’ buttons simultaneously, and switch on the ignition.
. All the control panel LED’s and all LCD segments will flash on and off. Any function LED indicator which does not
flash on / off suggests a fault condition within that area of the panel or, with the LED.
Any LCD element which fails to flash on
/ off indicates a fault within the panel or display element.
. Press ‘Auto’.
. Press ‘Face‘ to scroll through a maximum of 5 fault codes.
W
Thecontrol panel display will flash repeatedly indicating a list oftwo digit numbers (refer to following page for code
analysis).
. If, when a code is displayed, an accompanying ‘beep‘ is emitted, the indicated fault is current and therefore still pres- ent within the system. A code displayed without an accompanying ‘beep’ indicates a fault had previously occurred
but is not present within the system.
It is advisable to check all areas indicated with cleared fault codes. Such faults may re-occur if intermittent
problems are present in the system.
If
’0‘ is
displayed, there are no stored fault codes, wait 30 seconds to allow system self-test.
W:
. To delete stored and cleared fault codes simultaneously press ‘HRW and ‘FACE‘ switches.
. After investigating and correcting all stored faults, press the ‘Push Off button to restore normal operation with de-
fault panel settings, ie AUTO at 24OC.
Condition
IGN input at 12V, check LED is illuminated
AUX
input at 12V, check LED is illuminated
Clock
input normal, check LED is illuminated
Start input normal, check LED is illuminated
Data out input normal, check LED is illuminated
Dimmer override input
ON, check LED is illuminated
14.4.2 Panel Communications Check
Panel communications check verifies the inputs and outputs from the control panel to the A/ CCM.
To exit the panel communications check mode press the system ON button.
Issue 1 August 1994 10 X300 EDM
E I ect r ica I
15.1 SUPPLEMENTAL RESTRAINT SYSTEM
15.1.1 System Description
The Supplemental Restraint System (SRS) installation comprises:
0 electronic Diagnostic Module (DM)
0 driver and passenger-side air bag modules (including firing mechanisms)
0 two front impact sensors (left and right)
0 one safing sensor
0 dedicated wiring harness
0 two cable reel cassettes (integral part of the steering column harness)
0 Malfunction Indicator Lamp (MIL) and driver information message
The system is designed to provide protection for both driver and front seat passenger by automatically deploying air
bags in the event of a collision during forward travel. The driver
-side air bag is located in the centre of the steering
wheel assembly and the passenger-side air bag in the fascia panel.
In the event of a collision the impact
/ safing sensors operate, completing the electrical firing circuit and causing the
air bags to inflate within 32 milliseconds. At least two of the three sensors (at least one impact, and the safing sensor)
.must be activated to initiate firing. System operation is dependent upon battery voltage supplied directly, and via the
ignition switch, to the DM and the correct installation and operation of all system components, including the wiring
harness. Faults in system components, installation or wiring will be indicated by the MIL Lamp, located on the instru
- ment panel, which will illuminate 'SRS AIR BAG'. Indication is also given by the driver information message'AIR BAG'
displayed on the LCD panel below the speedometer.
15.1.2.1 Diagnostic Module (Fig. I)
The Diagnostic Module (DM), mounted below the passenger-side air bag module, behind the console fascia panel, is
the electronic microprocessor unit which monitors the whole SRS system. The state of the three system sensors, two
air bag modules and the wiring harness is monitored constantly to detect activation criteria and component faults.
15.1.2 COMPONENT DESCRIPTIONS
The unit also confirms correct supply conditions by compar- ing a direct battery voltage input with an input, via the igni- tion switch, of the same voltage value. Detection of system
faults will be relayed by the DM to the instrument panel and
the air bag MIL Lamp illuminated.
The DM contains a reserve power supply unit, enabling the
air bagsto fire even if supply voltage is lost during an impact
situation. The reserve power charge will be retained for ap
- proximately one minute after the positive supply voltage is
disconnected. An auxiliary internal circuit, known as the
'dwell enhancer', provides a temporary ground to compen
- sate for damaged primary crash sensors. If either primary
crash sensor operates for 5 milliseconds the 'dwell en- hancer' circuit will turn on, completing the firing circuit to
ground for 90 milliseconds. The purpose of this is to allow
air bag deployment even if the operated primary crash sen- sor circuit is defective or opens.
15.1.2.2 Wiring Harness
Fig. 1
A dedicated wiring harness, covered with yellow sheathing, independent of any other vehicle system, is used to electri- cally connect all the component items. To allow movement of the steering mechanism, two cable reel cassettes are
incorporated into the driver-side air bag module circuitry, as a means of compensating for steering wheel rotation is
required to prevent harness damage or disconnection. The two cable reel cassettes form an interface between the
steering column and air bag module and, due to their coiled construction, are able to contract or expand as required.
15.1.2.3 Air Bag Modules
The two air bag modules, driver and passenger side, are
each activated when either front impact sensor (Fig. 2) and
the safing sensor operate simultaneously. Both modules
contain a charge of sodium
azide/copper oxide which, when
ignited by an electrical impulse, generate a volume of ni
- trogen gassufficientto inflatetheair bag. Theamountof gas
generated is greater in the passenger-side air bag due to its
larger size. Both modules, including surrounding trim pan- els, are non-serviceable and once activated must be re-
newed as a complete assembly.
Fig. 2
X300 EDM 15.1 - 1 Issue 1 August 1994
Electrical IT
15.2.2 INSTRUMENT PACK CONNECTORS
0
Socket A (24-way)
Pin Circuit Input
1. Fuel used 2. 12V ignition feed 3. Ground 4. Ground 5. Battery feed 6. 12V auxiliary feed 7. Anti-lock fail 8. -
Socket 6 (48-way)
Pin Circuit Input
1. - 2. Speed output 1
3. Speed output 2
4. Trip stalk cycle 5. - 6. - 7- 8. - 9. Generator indicator voltage 10. Brake fluid level 11. - 12. Trip reset 13. Screenwash fluid level 14. Transmission sport mode 15. Seat belt 16. Luggage compartment open
Pin
9.
10.
11.
12.
13.
14.
15.
16.
Pin
17.
18.
19. 20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
Circuit Input
Illumination feed
-
- -
Diagnostic serial output (K) Diagnostic serial input (L)
Distance
-
Circuit Input
Park brake (on)
D.I.
bulb fail - - -
Check engine
Exhaust temperature
Main beam
- - - - - - - -
Fig. 1 Pin Locations
Pin
17.
18.
19.
20.
21.
22.
23.
24.
Pin
33.
34. 35.
36.
37.
38.
39. 40.
41.
42.
43.
44.
45.
46.
47.
48.
Circuit Input
-
Coolant temperature
Fuel level
Oil pressure
Coolant temperature output
Tachometer
input - ECM
-
Circuit Input
Ground - trip keyboard
Traction control status
Trip clear
Coolant level
Side lights (on)
Left D.I. (on)
Right D.I. (on)
Trip
km / miles
General bulb fail
Transmission fail
Air bag fail
Door ajar
- Driver’s
Door ajar - Passenger’s
-
X300 EDM 15.2 - 3 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
Electrical rl
CONNECTOR A2 - 22 PIN, WHITE
0 Pin No. I Description [ Input / Output I Signal
1 I Feedback +VE ref O/P I4.5v
2 Feedback -VE ref O/P ov
3 Headrest feedback I/P 140mV - 4.36V
4 Recline feedback I/P 140mV - 4.36V
5 Fore 1 aft feedback I/P 140mV - 4.36V
6 Cushion rear feedback I/P 140mV - 4.36V
7 Cushion front feedback I/P 140mV - 4.36V
8 Recline rearward switch I/P Switch to +12V
9 Fore / aft rearward switch I/P Switch to +12V
10 Fore 1 aft forward switch I/P Switch to +12V
1 11 Switch pack supply O/P +12v supply
- - r 12 Hardware link to 62/19
13
Auxiliary ground to lumbar O/P Switch to OV
14 Headrest lower switch I/P Switch to +12V ~
15 Headrest
raise switch I/P Switch to +12V
' 16 Cushion rear lower switch I/P Switch to +12V
0 17 Cushion rear raise switch I/P Switch to +12V
18 Cushion front lower switch I/P Switch to +12V
19 Cushion front raise switch I/P Switch to +12V
20 Recline forward switch I/P Switch to +12V
I 21 1 Input seat belt switch I I/P I Switch to OV I
I 22 I Hardware link to pin B2/1 I I- I -
0
18 Brake pedal pressed I/P Switch to OV
19
Hardwire link to A2112
20 O/P seat belt switch O/P Switch to OV
- -
21 Memory set I/P Switch to +12V
22 Dooropen I/P Switch to OV
X300 EDM 15.4 - 7 Issue 1 August 1994
IT Electrical
15.4.5 COLUMN / MIRROR CONTROL MODULE
The Column / Mirror Control Module C/ M CM controls the operation of position adjustment motors by acting upon
inputs from the relevant switches. The module also forms an interface with signals from associated systems which
affect column /mirror movement. The
C/ M CM works in conjunction with SCM and SL CM to provide positional adjust- ment memory functions as previously described.
There are three connectors to the
C I M CM single multi-pin socket, designated block A, B and C, which connect the
various inputs / outputs and peripheral devices to the module. Connections are as listed below.
I BLOCK A [26-WAY GREY) 1
I .. I I 41 Input Switched to 12V ..
20 Memory set selected
Input Switched to 12V
21
Tilt restrict ident Input Switched to ground 1 open
22 Key in ignition barrel active
Input Switched to ground
circuit
23
1 Auxiliary ground on Input 1 Switched to ground
24 1 Reference voltage +ve feedback output I4.5v
25 1 Passenger mirror R/L Output 1 +ve 1 -ve
26
1 Mirror motor common Output I +ve / -ve
BLOCK B (lgWAY, GREY)
Pin No. I Description I In / out lsignal
1 Driver mirror L/R feedback Input 140mV - 4.36V
2 Passenger U/D feedback
Input 140mV - 4.36V
3 Driver mirror U/D feedback Input 140mV - 4.36V
4 Column tilt feedback Input 140mV - 4.36V
5 Column reach feedback
input 140mV - 4.36V
6 Reverse gear selected
Input Switched to ground
-