
Automatic Transmission (AJ16) w 
8.1.5 
nector. 
TRANSMISSION  CONNECTOR 
(GB003) 
TRANSMISSION  ELECTRICAL PIN POINT TESTS 
THE FOLLOWING  TESTS describe  methods  of testing the  transmission  control solenoid  valves from the multi-pin con- 
0 A = Road Speed Sensor 
0 B = Pressure Regulator 
0 D = Oil Temperature  Signal 
0 F = Road Speed Sensor 
0 H = MVI Solenoid 
0 J = Oil Temperature  Ground 
0 K = MV2 Solenoid 
0 L = MWVK Solenoid 
0 M = Solenoid Supply 
The  solenoid  valves are located  on the  valve block  in the  transmission  assembly and can be identified by their  position. 
Connection  is made via  a connector  located on the  LHS  of the  transmission  assembly. 
Impedance  Checks 
M
-L) 
M
-K)  28-60ohm 
0 M-H) 
M-B 5-70hm 
M)(A 
K)(D 
L 1-( F O/C 
H)(J 
B)( 
L-K) 
L
- H ) 56- 120  ohm 
K
-H) 
L
-B) 
K
-B)  33-67ohm 
H
-B) 
All  Pins 
- Ground OK 
5 
m- 1738 
Fig. 1 Transmission  Multi-plug Connector 
X300 EDM 27 Issue 1 August  1994  

Automatic Transmission (V12) Powertrain 
Engine Speed 
The engine  speed is provided by  an open collector  signal supplied  from the engine  management  control module 
(ECM). 
Throttle Position 
This signal,  from the ECM,  performs the  following two functions: 
1. 
2. 
Engine  Torque  (and warm-up) 
This signal,  from the ECM,  performs the  following three functions: 
1.  During  cranking  to convey  the completion  of an  engine warm
-up  cycle  to TCM. 
2. To  convey engine  torque information,  under normal running  conditions, to TCM. 
3. To  convey engine  torque fault signals to TCM. 
Engine ‘warm
-up’  cycle commences  from ignition ON until 500ms after the engine  exceeds 400rpm. After this time 
delay  either  an engine torque,  or torque  fault signal  will be transmitted. 
Transmission Input Speed 
The  transmission  input speed sensor  is mounted  within the transmission housing  and produces a variable frequency 
signal,  directly  proportional  to forward  clutch housing rotational  speed which  is transmitted  to the  TCM.  Sensor resis- tance equals 1.25kQ f 0.25. 
Transmission  Output Speed 
The transmission  output speed sensor is mounted  within the transmission housing  and produces a variable frequency 
signal,  directly  proportional  to the  rear carrier  rotational speed which  is transmitted  to the  TCM.  Sensor resistance 
equals 
1.25w2 + 0.25. 
hake Application 
When a brake  application signal  is received, due  to brake  switch  operation,  the torque  convertor clutch  lock-up sole- noid  is de-energized,  releasing lock-up mode  if already  applied 
Transmission  Oil Temperature 
The  transmission oil temperature  sensor, located within the internal  harness,  monitors  oil temperature  and transmits a corresponding signal  to the  TCM. 
To convey  throttle position information  to the  TCM. 
To  indicate  fault conditions  between ECM and throttle  potentiometer. 
8.2.4.2 OUTPUTS 
Gear  Shift Solenoids 
The two  gear  shift solenoids, located  within the transmission  housing, determine  gear ratio  when  the selector  is in  any 
of the forward  gear positions. 
Force Motor 
The force  motor,  mounted within the transmission  housing acts as a transmission  torque fluid pressure regulator. 
Torque  Converter  Clutch (TCC) Solenoid 
The torque converter clutch  solenoid, mounted within the transmission  housing, provides a direct drive from the en- gine, via  the converter  clutch, to the driven  wheels, giving the  efficiency of a manual  gearbox.  The  solenoid also pro- vides a  ’ramp‘ apply and  release to engage / disengage  the clutch  gently. 
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X300 EDM Issue 1 August 1994 6  

Brakes (a) 
12.3 COMPONENT DESCRlPTlONS 
ABS / TC CM (3 Fig. 1) 
The ABS / TC CM,  located  just  below the  hydraulic valve 
block  on the  bulkhead,  is the system  controller  and pro- 
cesses  all thevarious information supplied  from the external 
sensors and  probes. The unit monitors  ABS / TC operation 
giving  fault indication  and disabling the  systems when de- fects are detected. The  unit is self  testing and  cannot be fault 
diagnosed  beyond 'black box' level i.e. faulty  module. Sys- 
tem fault  codes  are stored  in a non-volatile memory  for in- terrogation by external diagnostic  equipment. 
Solenoid Valves (2 Fig. 1) 
The solenoid  operated  hydraulic  valves, located  within the 
hydraulic module  valve block,  regulate  the supply of pres- sure to the braking circuits allowing individual control of all wheels  with a full  ABS  /TC system. 
Nnfe: For ABS  only,  the driving  (rear) wheels  are con- 
trolled by a common braking circuit. 
The  traction control  system isolating  valve has the 
same  characteristics  as 
a normally open valve. a 
Hydraulic  Pump /Motor  Unit (1 Fig. 1) 
This unit,  located above  the hydraulic valve  block, ensures 
that  brake  fluid is transmitted around the  system at the cor- rect operating  pressure.  The  250W ds. motor  draws  32A 
current at peak  operation  and has an internal  resistance  of 0.m. 
Wheel Speed Sensors (Fig. 2) 
The four  wheel  speed sensors are  identical in function  and 
construction.  Wheel rotation  creates the signal  within the 
sensor.  This signal is supplied  to the  ABS  /TC 
CM where it provides  wheel speed  information.  The sensor  coil has a re- sistance  value of 1.1 k Q and  will have  a voltage of 2.5V pres- ent on each  connecting  pin when the  vehicle is stationary. 
Throttle  Flap Actuator  Motor / Position Sensor (Fig. 3) 
The throttle  flap actuator motor,  mounted adjacent tothe hy- draulic control  unit, adjusts throttle position, irrespective  of 
accelerator pedal  position,  by  regulating throttle  opening 
when  traction  control  is demanded.  The actuator  motor 
nominal  12V terminal  voltage  is supplied  by  ABS 
/ TC CMduring normal operation.  The motor  has an  internal re- sistance  of approximately 1.6Q. The throttle position  sensor 
supplies  information  relative to the position of its  centre tap 
to  the  ABS 
/ TC CM which  regulates actuator  movement. 
The sensor  has a resistance  of 6.4 K!2. Aterminal  voltage of 5V is supplied by ABS/TC CM to  connection 3 during normal 
operation,voltage between connections  1 and 2 will  vary  be- tween 0 and 5V dependant  on wiper position. 
Fig. 1 
Fig. 2 
Jrn 270 
Fia. 3 
X300 EDM 5 Issue 1 August 1994  

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 
0 
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. 
0 
X300 EDM 15.2 - 1 Issue 1 August 1994  

Electrical rl 
JOS 1776 
1. Instrument  Pack 7. Powerwash  Relay 
2.  Body Processor  Unit 
(BPU) 8. Washer Fluid Level Sensor 
3. Oil Pressure Sensor 9. Brake Fluid Level Sensor 
4. Coolant  Level Sensor 10. Ignition Switch 5. Coolant  Temperature  Sensor  11. Column Switch 
6. Coolant  Recirculation  Pump Relay  12. Fuel  Tank  Level Sensor 
Fig.  1  Component  Location Diagram  

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