12.1 ANTI-LOCK BRAKING SYSTEM (ASS), GENERAL DESCRIPTION
The anti-lock braking system (ABS) components are combined with a hydraulic booster and tandem master cylinder (TMC) to provide a two-circuit braking system. The anti-lock braking system comprises the following components:
0 Four inductive wheel speed sensors, hub end mounted
0 ABS warning light
0 Hydraulic module.
The hydraulic module consists of an electric motor driven pump,
two low pressure accumulators, valve block and an
ABS electronic control module.
m: Electronic control modules for vehicles without traction control are designated ABS CM. Control modules for
vehicles with traction control are designated ABS /TC CM.
The valve block houses solenoid operated valves which are activated by voltage signals from the control module. The
signals are generated using wheel speed information received from the wheel speed sensors.
For vehicles without traction control the valves operate on three circuits, two front and one rear, as necessary to pre
- vent wheel locking during braking. Brake pressure is modulated individually at thefront wheels and collectively at the
rear. Rear wheel control operates on a 'select low' principle i.e. locking in either wheel is sensed, and controlled brake
pressure is applied to both wheels.
For vehicles with traction control the valves operate on four circuits. During ABS control the rear wheel are controlled
on a 'select low' principle (as above), but during traction control operation the rear wheels are controlled individually.
0
1yQfB: Functional and diagnostic information for the ABS CM and the ABS/TC CM is contained in the Electrical Diag-
nostic Manual (EDM), Section 12.
ABS Warning lamp / Traction Control Warning lamp /Fluid level Indicator
The ABS and traction control warning lamps, mounted in the instrument panel, indicate a fault in the ABS or traction
control. These systems are inhibited or disabled when the lamps are lit, although conventional braking is unaffected.
When the ignition is switched on, an ABS self test is initiated. During this test, the ABS and traction control warning
lamps are
lit for approximately 1.7 seconds and then extinguish. A fault is indicated if the warning lamps remain lit or
come on whilst the vehicle is being driven.
W: The ABS self test is masked by the 5 second lamp test initiated when the ignition is switched on.
The fluid level indicator lamp, mounted in the instrument panel, is
lit when the brake fluid falls below the minimum
mark on the brake fluid reservoir.
ABS / Traction Control - Inhibit / Disable
Faults conditions are detected by the ABS/TC CM which disables the ABS and traction control until the fault is rectified.
The ABS and traction control warning lights on the instrument pack remains lit whilst a fault exists. The system will
be disabled when the following conditions occur:
0
0 Valve failure
0 Sensor failure
0 Main driver failure (internal ABS /TC CM fault)
0 Redundancy error (internal ABS JTC CM fault)
0 Overvoltage J undervoltage
0 Pump motor failure.
0 Throttle valve actuator motor failure (traction control vehicles only).
0 Throttle valve actuator potentiometer failure (traction control warning light only).
X300 VSM 1 Issue 1 August 1994
The input frequency from each wheel speed sensor signal is translated by the ABS I TC CM, into a comparable wheel
speed. The ABS / TC CM continually monitors the system. False wheel speed information, such as sudden speed
changes in excess of 20 km / h or excessive speeds, are detected as a 'sensor malfunction'. The ABS / TC CM reacts
to fault conditions in the following ways:
Inhibit- ABS/traction control is inhibited until the sensed speed returns to within an acceptable limit, whereupon ABS
/traction control is restored. Conventional braking is unaffected. Depending on vehicle speed the ABS/traction control
warning lights may come on.
DisaMe - ABS /traction control is Disabled (switched off) and the ABS /traction control warning lights come on. The
system will not be restored until the engine is switched off and restarted orthe fault has been rectified. Afterthe system
has been disabled, the warning lamps remain on until the vehicle has reached a speed of 20 km/ h during thefirst igni- tion cycle after fault rectification.
Full diagnostic information for the ABS /TC
CM is given in the Electrical Diagnostic Manual (EDM), Section 12.
Issue 1 August 1994 2 X300 VSM
Brakes (e#
12.1.7. Parking Brake
J70 293
W
1. Parking brake lever 2. Front cable 3. Relay lever 4. Driveshaft securing bracket 5. Intermediate cable 6. Cable equalizer
7. In-line cable connector 8. Rear cable RH 9. Rear cable LH
10. Parking brake switch and harness 11. Parking brake warning lamp
Fig.
1 Parking Brake Layout
All vehicles are fitted with identical parking brake systems.
When the parking brake lever
is operated, the cable system applies equal force to both RH and LH brakeshoe expander
assemblies. The brake shoes expand and press against the hub assembly, locking the rear wheels.
The handbrake lever, ratchet assembly and warning
light switch (item 1) are mounted on the transmission tunnel by means of threeflanged screws a blanking plate and gasket. The front cable (item 2) is connected to the relay lever (item 3) which is mounted on the driveshaft securing bracket (item 4). The relay lever operates the intermediate cable (item 5) which incorporates an adjusting screw to allow cable tension to be adjusted. The intermediate cable operates the
equalizer which ensures that equal force is applied to RH and LH parking brakesvia rearcable RH (item 8) and rear cable
LH (item 9). The rear cables are adjustable to allow cable tension to be adjusted.
The park brake switch (item 10) latches when the lever
is operated and lights the parking brake warning light (item 11 mounted in the instrument panel.
X300 VSM Issue 1 August 1994
13.4 TRUNK
13.4.1 Trunk, Description
The trunk houses the spare wheel, the battery, an electrical carrier containing electrical fuses, relays and modules and
a compact disc auto-changer attached to body bracketry. The trunk is fitted with push-fit, velour finish, liners (1 Fig. 1) to the sides and front inner panel; the trunk floor is covered with carpet attached to a removable floor board (2 Fig. 1) and a battery cover (3 Fig. I), one covering the spare wheel and wheel changing equipment, the other covering the
battery and electrical carrier.
The floor board rests on the spare wheel, the front and rear edges
of the floor board locating in blocks on the fuel tank
backboard and on the rear of the body. The blocks accommodate the two possible height settings caused by the differ- ence in thickness between the space saver and full sized spare wheels.
A tread plate (4 Fig. 1) is attached to the trunk sill and a liner is fitted to the rear of the trunk below the sill. Interior trim finisher panels are fitted to the rear lamp units accessed from the trunk opening.
The trunk lid
(5 Fig. 1) is fitted with a removable moulded liner and two trunk illumination lights; the lid is supported by two gas struts, attached through press-on fittings between the inner wheel arch and trunk hinge (6 Fig. 1). A warning
triangle is attached by a bracket to the trunk lid and retained in the open position by a rubber block (Europe inc UK only).
Trunk locking is based on a central latch and striker, operated electrically through the central locking system
by an ad- jacent actuator or by key in a barrel lock located behind the trunk lid badge.
For details on renewal
of trunk front and side liners, trunk carpet, trunk seal retainer and battery cover, see relevant
Service Repair Operations.
2 4 3 J76-1056
1. Trunk Liners 2. Removable floor board 3. Battery cover
4. Treadplate 5. Trunk lid 6. Hinge
Fig.
1 Trunk Components and Trim
Issue 1 August 1994 X300 VSM 38
IT Electrical
15.2.8 Odometer
With the ignition 'OFF' the odometer is permanently dis-
played but not illuminated. With the ignition 'ON' the odo- meter is displayed and also illuminated.
Trip information or driver information messages may be dis
-
played instead of the 'ODO'. By pressing the 'ODO' button
once or twice the trip and driver information messages can
be deleted and the
'ODO rdisplayed.
W. The odometer value is not stored within the LCD
module.
15.2.9 Trip Computev
This provides information on the vehicle's speed, fuel usage
and distance traveled
all of which are calculated by a micro
processor.
The controls, part of the fascia switch assembly, are located
on the right
-hand side pod positioned to the right-hand side
of the steering column.
I
/
J86-192L
Fig. 1
15.2.10 Driver Information Messages
Two fault messages, FLUID - AIRBAG are displayed via the LCD in conjunction with relevant warning lamps.
If an
airbag fault exists or the brake fluid is low, a message will automatically be displayed on the LCD and the relevant
warning lights illuminated. Should both faults exist at the same time, each message is displayed alternatively for ap
- proximately 2 seconds.
Messages may becancelled
by pressing the 'ODO button which allowsthe LCD to return to its last displayed message.
The warning lamps will not be extinguished. If the fault is not repaired the message(s) and the warning lamp(s) will
be redisplayed when the ignition is switched on.
15.2.11 /llumination
Warning indicator lamp illumination is controlled by a microprocessor located inside the instrument panel.
The seven right
-hand warning indicators are primary warning lamps illuminating 'RED and the seven left-hand warn-
ing indicators are secondary warning lamps illuminating 'AMBER'
The eight lower lamps are
a mixture of status and warning lamps.
With the ignition
'OFF' the LCD is not illuminated.
With ignition
'ON' and side lights 'OFF' the LCD is illuminated at maximum brightness.
With the ignition on and side lights
'OFF' the LCD is dimmed as are the gauges.
The long
life type bulbs are enclosed by orange and brown coloured bulb holders which must never be interchanged.
Replacement bulbs must always be of the same colour.
CAUTIQN: Always dwonnect the battery ground lead before commencing with any instrument rsimwal procedure.
15.2.12 General Repair Notes
0 After lens removal do not rest instrument panel face down as this causes damage to the delicate gauge needles.
Avoid scratching the gauge faces and ensure cleanliness when handling the panel.
0 To minimize the risk of damage and contamination to the instrument panel, all repairs must be carried out in a non - static and dust -free environment. Avoid touching connector pins and pcb components to minimize
risk of static damage.
0 The instrument panel has two different types of bulb holders each of which must be located correctly when
changing the bulbs.
Issue 1 August 1994 10 X300 VSM
15.6.2.2 Programmed Wash / Wipe Operation
The end of the switch lever must be pressed inwards for the windscreen wash and wipe operation. Wash / wipe con- tinues for as long as the lever is pressed.
When released, the windscreen wiper stops immediately and the wiper blades sweep for
a further three wipes.
On pressing the end of the switch lever inward and then releasing
it, the windscreen washers operate for approximately
two seconds before stopping, whilst the wiper blade continues for a further three wipes.
N&: If the end of the switch lever is pressed while the washer fluid warning light is illuminated, the windscreen
washers, but not the wiper blade continues to operate.
0
15.6.2.3 Headlamp Power Wash Operation (where fitfed)
The headlamp power wash operates only when the programmed washer/ wipe function is selected and the side lights
are 'ON'
The headlamp power wash does not operate if the windscreen washer reservoir fluid lever is low. This is indicated
by the washer fluid level warning light illuminating.
&&: The headlamp power wash only operates on the 1st and every 6th succeeding cycle of the programme wash /wipe switch, after the ignition switch has been turned to position '11'.
X300 VSM 17 Issue 1 August 1994
Clear
(amps) 1
Circuit
I
25 5 Power amplifier - radio / cassette and compact disc player (where
fitted)
Tail lamp
- left-hand side
Number plate lamp
- left-hand side I Back-up lights
Stop lamp
- left-hand side
Turn indicator
- rear left-hand side
F3 Light Blue
F4 Red 10 Security system
F5 Red 10 Body processor unit (BPU)
F6 Tan 5 Data link connector
F7 Light Green 30 Fuel pump
F8 Light Blue 15 Luggage compartment remote release
F9 Light Blue 15 i Rear fog guard lamps
Radio
telephone (where fitted)
1
Aerial, Radio /cassette and compact disc player memory feed.
Stop lamp
- right-hand side
1 Turn indicator - rear right-hand side I.
I FIO Tan 5 i Radio / cassette and compact disc player control relay
F11 Clear 25 1 Caravan /Trailer module I
t F12 Tan 5 ~ Accessories
and telephone control relay I I
I I I F13 Red 10 ~ Accessories 1 1 I I F14 - - I Not used 1 I I F15 Clear 25 1 Heated
rear window I I I F16 Tan 5 1 Airbag warning
Luggage Compartment Fuse Box
Issue 1 August 1994 AI-95MY 18 X300 VSM
L F18 Tan 5 Tail lamp - right-hand side
License plate lamp - right-hand side
Security System
Pin No. Signal Description
01 0 / P Deadlock (front right / rear left)
02
0 / P Unlock driver's door
03
Connections to the SLCM are detailed in the following table:
9 Connector A (26-way)
Comment
switch to ground 200mA
switch to ground 200mA
05 I/P
06
0 / P
07
08 O/P
09
0 / P
10 0 / P Vehiclespeed
7600 pulses
/ mile
Inclination alarm
Intelligent sounder serial communications
Memoryseat2
Visual warning switch to ground
Secure mode status arm:
200Hz square wave f 5%
400Hz square wave f 5%
switch
to
+12V for 500ms
disarm:
duration: 64ms
0
117- I I
11 0 / P Trunk lid release relay 1 switch to ground
12
I / P Power +12V battery 1 + 12V power supply
13 O/P
Sounder+ve half of push pull network
14
0 / P Deadlock
(front left / rear right) switch to ground (200mA)
15 O/P Lock relay switch
to ground (200mA)
18
19
20 21 O/P
AlarmLED switch
to +12V (20mA)
0 / P Start inhibited coded communication
0 / P Memorv seat 1 switch
to +12V for 500ms
Connector 8 (16-way)
22
23
24
25
26 O/P
Allclose switch
to ground
0 / P
O/P Horn relay switch to ground
(200ms)
I/P Powerground OV (nominal)
OJP Sounder-ve
Interior lights
on switch
to ground for 80ms
f 5%
01
I
02
03 04
05
06
07
08
09
I I I I 15 I I / P I R.F. sianal
Intrusion
sensor
(RH) ground screen
0 / P Intrusion sensor (RH) 40kHz
I / P Intrusion sensor (RH) signal
0 / P Intrusion sensor (RH) +8V
Ground
R.F. ground
Diagnostic
IS0 K line
I. I - I 16 I I Diaanostic IS0 L line 1 diagnostic link input
10
11
12
13
14
.I
I I" 1- I
Intrusion sensor (LH) ground
0 / P Intrusion sensor (LH) 40kHz
I / P Intrusion sensor (LH) signal
0 / P Intrusion sensor (LH) +8V
Ground
Issue 1 August 1994 X300 VSM 5
84
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