
Electrical IT 
SECTION CONTENTS 
Sub
-Section 15.2 lnsfrumenfs 
Subsection  Title SRO Page 
15.2 ............. Instruments .................................................................... 15.2-1 
15.2.1 
............ Introduction .................................................................... 15.2-1 
15.2.2 
............ Instrument  Pack Connectors - Pin Locations ......................................... 15.2-3 
15.2.3 
............ Component Description .......................................................... 15.24 
15.2.3.1 .......... Speedometer ................................................................... 15.24 
15.2.3.2 .......... Tachometer .................................................................... 15.24 
15.2.3.3 
.......... Engine  Oil Pressure  and Warning  Lamp ............................................. 15.24 
15.2.3.4 .......... Engine Coolant  Temperature ...................................................... 15.24 
15.2.3.5 .......... Fuel Tank  Level  Gauge and  Warning Lamp .......................................... 15.24 
15.2.3.6 
.......... Battery  Voltage Gauge and  Warning Lamp .......................................... 15.24 
15.2.3.7 
.......... Liquid  Crystal  Display ........................................................... 15.24 
15.2.3.8 .......... Trip Computer .................................................................. 15.2-5 
15.2.4 
............ Primary  Warning  Lamps (Illuminated  Red) .......................................... 15.2-5 
15.2.4.1 
.......... Exhaust  Temperature ............................................................ 15.2-5 
15.2.4.2 
.......... Low  Oil Pressure ................................................................ 15.2-5 
15.2.4.3 
.......... Seat  Belt ....................................................................... \
15.2-5 
15.2.4.4 
.......... Trunk  Lid Open ................................................................. 15.2-5 
15.2.4.5 
.......... DoorAjar ...................................................................... 15.2-5 
15.2.4.6 
.......... Engine  Coolant LeveL ............................................................ 15.24 
15.2.4.7 
.......... SRS Airbag Fault ................................................................ 15.24 
15.2.4.8 .......... Charging Fault .................................................................. 15.24 
15.2.4.9 .......... Brake System  Fault .............................................................. 15.24 
15.2.4.10 ......... Bark Brake ..................................................................... 15.24 
15.2.5. ........... Secondary  Warning Lamps (Illuminated Amber) ...................................... 15.2-7 
15.2.5.1 
.......... Transmission Fault ............................................................... 15.2-7 
15.2.5.2 
.......... Washer  Fluid Level .............................................................. 15.2-7 
15.2.5.3 
.......... Bulb  Fail ....................................................................... \
15.2-7 
15.2.5.4 
.......... Traction  Control Fail ............................................................. 15.2-7 
15.2.5.5 
.......... Anti-lock  Fail .................................................................. 15.2-7 
15.2.5.6 
.......... Low  Fuel Level ................................................................. 15.2-7 
15.2.5.7 
.......... Check  Engine ................................................................... 15.2-7 
15.2.6.1 
.......... Transmission Sport  Mode ......................................................... 15.2-8 
15.2.6.2 
.......... Traction  Control OFF ............................................................ 15.2-8 
15.2.6.3 
.......... Direction  Indicators ............................................................. 15.2-8 
15.2.6.4 
.......... Main  Beam .................................................................... 15.2-8 
15.2.6 
............ Status 
and Warning  Lamps ........................................................ 15.2-8 
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X300 EDM ii Issue 1 August 1994  

Electrical IT 
SECTION CON TENTS 
Subsection 15.2 Instruments  (continued) 
Sub-Section  Title SRO Page 
15.2.7 ............ Fault Diagnosis ................................................................. 15.2-9 
15.2.7.1 
.......... Active High  /Low Inputs ......................................................... 15.2-9 
15.2.8. 
........... Instrument  Pack Pin-point  Tests .................................................. 15.2-1 0 
15.2.8.1 .......... Oil Pressure,  Battery Condition,  Coolant Temperature  and Fuel  Gauges ................. 15.2-1 0 
75.2.8.2 
.......... Speedometer .................................................................. 15.2-10 
15.2.8.4 
.......... Liquid  Crystal  Display .......................................................... 15.2-17 
15.2.8.6 
.......... Door Open  Warning Lamp ...................................................... 15.2-12 
15.2.8.7 
.......... Exhaust  Temperature  Warning Lamp .............................................. 15.2-1 3 
15.2.8.8 .......... Luggage Compartment  Warning Lamp ............................................. 15.2-14 
15.2.8.9 
.......... Seat  Belt Warning Indicator ...................................................... 15.2-1 5 
15.2.8.3 
.......... Tachometer ................................................................... 15.2-11 
15.2.8.5 
.......... Trip Computer ................................................................. 15.2-11 
15.2.8.70 
......... Park  Brake  Indicator ............................................................ 15.2-16 
15.2.8.71 
......... Main  Beam  Indicator ........................................................... 15.2-17 
75.2.8.12 
......... Direction  Indicator Tell Tales ..................................................... 15.2-18 
15.2.8.14 
......... Washer  Fluid Level  Indicator ..................................................... 15.2-20 
15.2.8.16 
......... Brake  Fluid Level  Indicator ...................................................... 15.2-22 
75.2.8.17 
......... General  Bulb Failure  Indicator ................................................... 15.2-23 
15.2.8.18 
......... 
75.2.8.19 ......... 
15.2.8.20 ......... Traction  Control OFF Tell-tale .................................................... 15.2-24 
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75.2.8.13 ......... Generator IND Voltage Indicator ................................................. 15.2-19 
7 5.2.8.15 ......... Engine Coolant  Level indicator ................................................... 15.2-2 1 
Transmission  Sport mode  Indicator ................................................ 75.2-24 
Traction  Control Failure Warning  Lamp 
............................................ 15.2-24 
15.2.8.21 
......... Anti-lock  Failure  Warning  Lamp .................................................. 15.2-24 
15.2.8.22 
......... Check  Engine  Warning  Lamp .................................................... 75.2-24 
Issue 1 August 1994 iii X300 EDM  

Electrical n 
15.2 INSTRUMENTS 
15.2.1 Introduction 
The instrument  pack is a self-contained,  removable unit, which  incorporates all the main  display gauges and  warning 
indicators that  are used  to present vehicle  condition information.  The instrument  pack is programmed during  vehicle 
build,  to match  the vehicle's  individual requirements using  'Programmable Electronic Control Units System' 
(PECUS). This is achieved  via the diagnostic  communication  line, and therefore,  should be renewed  like-for-like.  The primary 
function  of the instrument display is  to provide the driver  with information  usual to normal  driving requirements.  The 
secondary  function is to  display  trip computer information. 
The  trip computer functions  are selected via the  steering  column stalk switch 
(LH). The messages are  displayed in the 
following  order: 
Odometer 
- Distance - Range - Fuel  Used -Average  Fuel -Average Speed - Instant Fuel - Odometer  (return). 
Two  trip computer  switches, 'Reset' and 'Odo',  are incorporated  into the facia  switch  panel. 
Instrument  pack information  is received from sensors  positioned 
at various locations  about the vehicle  (Fig. 1, follow- 
ing  page)  via one  of the  two  multi-pin sockets  located at the rear  of the instrument  pack. 
Information concerning  vehicle condition  and operation is  displayed in one  of three  ways: 
0 Information  necessary to confirm  normal vehicle operation:  road speed,  engine  speed, oil pressure,  battery 
condition, fuel  level, coolant  temperature.  This  information is displayed  using analogue  gauges. 
0 Information indicating the  presence of a hazard/fault condition (low oil pressure/door open  etc.) or operational 
action (indicator flashing / headlamp  full beam  'on'  etc.).  This information  is provided by twenty  two warning 
lampsltell-tales, arranged  in four  groups;  two groups of  seven at the left and  right  sides  of the instrument  pack 
and  two  groups  of four 
at the  bottom  of the instrument  pack. 
0 A Liquid  Crystal  Display  (LCD) is located at the  bottom-centre of the instrument  pack and is  normally  used to 
display the  odometer reading, but it can also  be used  to display  SRS fault conditions  and trip computer informa- 
tion  such  as vehicle  speed, fuel usage  and distance  travelled. 
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X300 EDM 15.2 - 1 Issue 1 August 1994  

rl E I ect r i ca I 
15.2.6 STATUS AND WARNING LAMPS 
15.2.6.1  Transmission Sport Mode (green) 
The transmission sport mode indicator is controlled  by a signal from the Transmission  Control Module (TCM). The 
indicator is illuminated  whenever 'Sport' mode is selected; a low  signal  is sent  to the instrument  pack (pin 14,48-way connector). 
15.2.6.2  Traction Control OFF (green) 
Two traction control lamps  are provided: control fail and  control off. Both  lamps  are controlled  from one input  from 
the  ABS I TC control  module. 
Under  normal operating  conditions, the input signal should  be high. 
If the input line  is continuously  low, traction con- trol has failed  and both  lamps  will illuminate. If the input signal  is a 4 Hz square wave the traction control  system is 
switched  off, therefore  the 'traction 
off lamp  will illuminate. 
15.2.6.3 
The  operation of the direction indicator  'tell-tales' is controlled  by the BPU. The 'tell-tales'  are the  only indicators on 
the instrument  pack which  can be illuminated  with the ignition OFF, for hazard  warning. 
The  signal  from the BPU  to the instrument  pack is pulsed,  switching  the direction indicators on  and 
off at the correct 
frequency.  The 'tell-tales'will illuminate when the signal is low. If the frequency  doubles, this signifies that  an exterior 
direction indicator  bulb has failed;  the bulb failure warning lamp should  also be illuminated. 
The  signal  is fed  to two  separate  inputs to the instrument  pack, on the  48
-way  connector;  pin 40 for LH directional  indi- cator 'tell-tale' and pin 41 for RH. 
!We: If both  direction indicator  'tell-tales'  are permanently illuminated; this  indicates that the BPU  has not been 
PECUS  programmed.  Check that a PECUS  label is attached  to the  BPU. 
Direction  Indicators - LH & RH (green) 
15.2.6.4  Main Beam  (blue) 
A low  signal  is supplied  to the instrument  pack (pin 24,48-way, connector)  from the BPU  when main  beam is selected. 
This illuminates the main  beam 'tell-tail' indicator lamp. 
Issue 1 August 1994 15.2 - 8 X300 EDM  

E I ect r ica I rl 
15.2.8.11 Main Beam  Indicator (Active low) 
1. Measure  voltage at pack pin 24,48-way connector, 0 volts indicates signal  low ie lamp ON. A value of 12V at pin 
24 indicates  main beam (and lamp) off. 
(4E WAY) P24 
1 
1. Instrument pack 9. Body processor  unit 
I -1 
I> (iP, 9 I 
UP 
J86-1843 
Fig. 1 Main Beam  Indication 
X300 EDM 15.2 - 17 Issue 1 August 1994