Land Rover Range Rover Etm 1995 4th Edition Rover Manual

							MULTIPORT FUEL INJECTION (MFI±V8)A1
15CIRCUIT DIAGRAM
30
F 1
10 AZ238
Body Electrical
Control Module
(BECM)
See Fuse Details
2 C505
7 C258Z132
Engine Control
Module (ECM)
S205
4C506GUC106
8C102
C202
19 C242
414
Z142
Instrument
Cluster
[15] Control Unit
and Mess-
age Centre
Display
15 C24251331221887
LG
3
C256
LG
11
OG
9
OG
1
RG
10
RG
2
BG
5
BG
14
B
E254
Z238
Body Electrical
Control Module
(BECM)[15]
P P
17
BMALFUNCTION
INDICATOR LAMP
(CHECK ENGINE)SERVICE REMINDER
INDICATOR
(SERVICE ENGINE) 
						

							MULTIPORT FUEL INJECTION (MFI±V8)A1
16CIRCUIT DIAGRAM
C509 1314
Z132
Engine Control
Module (ECM)
S509
Z261
Ignition Coils
151 3 2 4 C525 11&6 2&3 4&7 5&8 5 C525W
See Fuse DetailsP125a
Engine Compart-
ment Fuse Box
15
F 26
20 A
WB WU WY WK
R
RR R
UO PG
C508 8 
						

							DIESELA6
CIRCUIT OPERATION1
CIRCUIT OPERATION
Sensors
Engine Speed Sensor (X255)
The engine speed signal is crucial to the system, as
the information from the sensor is used in virtually all
of the strategies within the `DDE (Digital Diesel
Electronics) and its Engine Control Module (ECM)
(Z132). Through this sensor, the ECM (Z132) knows
if the engine is turning, how fast it is turning and
approximately where the engine is in its cycle. The
sensor is of the `Hall effect type, which sends out a
pulse to the ECM (Z132) every time a `tooth is
sensed on the flywheel (the flywheel has six `teeth).
If the sensor fails, then the warning lamp is activated
and the ECM (Z132) enters a `limp home mode
where the ECM (Z132) looks at the signal from the
needle lift sensor in one of the injectors. The needle
lift sensor gives one pulse per injection, i.e. one
pulse per twelve engine speed sensor pulses. The
response of the ECM (Z132) to changes in engine
parameters will, therefore, be considerably slower,
and a higher idle speed is initiated to try to
compensate at low engine speeds.
Needle Lift Sensor (X318)
The engine has six diesel fuel injectors, one of which
has a sensing element at the tip which informs the
ECM (Z132) exactly when the injector fires (the
`beginning of injection signal). The ECM (Z132) uses
this to correct the injection timing and also to back
up the engine speed signal in case that sensor fails.
If this sensor fails, the warning lamp will switch on
and the vehicle will enter `limp home mode with
reduced engine power/performance and lack of
throttle response (as there is a lack of feedback on
the injection timing).
Engine Coolant Temperature Sensor (X126)
This sensor is a `thermistor (a temperature
dependent resistor) where the voltage output varies
in proportion to coolant temperature. The ECM
(Z132) uses this information in many strategies, i.e.
to correct the injected fuel quantity and timing
(especially during cold starts), length of glow plug
timing, etc. The sensor is located in the top of the
engine block. In case of a failure, the warning lamp
is not activated and the ECM (Z132) selects a
substitute value of 50
C for glow plug and ignition
timing and uses the fuel temperature to correct the
fuel quantity, glow plug timing will not be correct,
possibly resulting in long crank times in cold weatheras well as slight fuelling effects. These symptoms
may not be noticeable.
Air Temperature Sensor (X311)
This sensor is another thermistor, located in the inlet
manifold, just after the intercooler, and measures the
actual temperature of the turbo booster air entering
the engine. To calculate the maximum amount of
injected fuel allowed, the ECM (Z132) needs to know
the volume of air flowing into the engine. Normally a
bulky, heavy and expensive air flow meter is
necessary, but the ECM (Z132) can calculate the air
flow from the air temperature and air pressure, so
eliminating the need for an air flow meter. If the air
temperature sensor fails, a substitute value of 30
C
is used, so by producing an incorrect air flow reading
and a reduction in engine power. 
						

							DIESELA6
CIRCUIT OPERATION2
Boost Pressure Sensor
The boost pressure sensor signal is used in
conjunction with the air temperature signal to
calculate volume air flow into the engine. The sensor
is located on the rear bulkhead, with the pressure
tap just after the charge air cooler. If the sensor fails,
a substitute value of 490 hPa is used by the ECM
(Z132), producing a reduction in power due to a fuel
quantity limiting to 21mg/stroke.
Throttle Position Sensor (X171)
The DDE system is a `Drive by Wire system i.e. the
throttle pedal does not directly control a throttle disc
or the amount of fuel injected into the engine, but
accelerator movements or `drivers request are
sensed and the information is passed to the ECM
(Z132). The ECM (Z132) calculates the maximum
allowable fuel quantity from the air flow into the
engine, engine speed, temperature, etc. It also
includes information from strategies such as smoke
limitation, active surge damping, automatic gear
change, fuel reduction, etc. to calculate the final
figure. When driving, if the `drivers request signal is
smaller than the maximum allowable quantity, then
the requested quantity is injected. However, if the
requested quantity is greater than the maximum
allowable, then the latter quantity is injected rather
than the drivers demand. Therefore the Throttle
Position Sensor (X171) is very important to the
system. It is located within the cab, close to the
pedal assembly itself. The unit consists of a
potentiometer and has three outputs:
1. Throttle Position ± pin 37 ECM (Z132)
The sensor outputs the pedal position to the ECM
(Z132), which uses the information as described
above.
2. Idle Position Switch ± pin 25 ECM (Z132).
The sensor has a separate idle position switch which
informs the ECM (Z132) of the pedal status in the
form of a simple on/off signal. This information is
used by the ECM (Z132) to implement 
idle speed
control and other strategies i.e. 
overrun fuel
shut±off.
3. Kick Down Switch.
This switch is currently not used.
Fuel Temperature Sensor
A thermistor is also located inside the injection
pump. The fuel temperature sensor signal is used to
adjust the quantity of injected fuel, especially during
temperature extremes. The signal is also used to
back up the Engine Coolant Temperature Sensor
(X126). If this sensor fails, the ECM (Z132) uses asubstitute value of 60C and only slight effects on
fuelling may possibly be noted.
Fuel Quantity Feedback Sensor
Located within the injection pump, this sensor sends
the ECM (Z132) information regarding the actual
quantity of fuel injected. Failure of the sensor or
corrupted signals will illuminate the warning lamp
and cause the engine to stall or not start. A second
check, a plausibility check against the needle lift
sensor, also takes place. 
						

							DIESELA6
CIRCUIT OPERATION3
Fuel Quantity Actuator
Once again located within the injection pump, this is
a moving magnet actuator, failure of which will cause
the engine to stall or not start as the ECM (Z132) will
activate the Fuel Shut±Off Solenoid (K111).
Injection Timing (Solenoid Valve Injection Timing
Device (K229))
This is another actuator within the injection pump.
The ECM (Z132) receives a signal from the needle
lift sensor and attempts to correct the injection timing
accordingly. If a change does not occur, then the
ECM (Z132) assumes a fault exists, activates the
warning lamp and reduces the quantity of injected
fuel.
Fuel Shut±Off Solenoid (K111)
The Fuel Shut±Off Solenoid (K111) shuts the engine
down if the ECM (Z132) detects a major fault.
Failure of the valve itself does not activate the
warning lamp, although if a short circuit occurs, the
engine will shut down.
Cruise Control
Due to the DDE system being 
drive by wire, a
cruise control feature is supplied in the ECM (Z132)
itself. Activation is via the steering wheel switches to
a converter box and on a single line to the ECM
(Z132). Failure of the signal results in cruise control
not working.
Brake Switches
The ECM (Z132) has two brake inputs, each of
opposite polarity. Comparison of the polarity states
provides the ECM (Z132) with a brake sense (i.e. if
switch 1 high and switch 2 low going to switch 1 low
and switch 2 high) and so cancels cruise control. If
both switches are the same polarity, the ECM (Z132)
senses a fault and does not allow cruise control.
Vehicle Speed Signal
The ECM (Z132) takes this signal from the
Anti±Lock Brake System ECU (Z108) and uses the
information for cruise control and 
active surge
damping. Failure of the signal results in cruise
disallowed and temporary lack of surge damping (i.e.
hard acceleration will cause the vehicle to surge
slightly). After 10 sec. a substitute value of 150 km/his used. Surging will reduce so as to be hardly
noticeable.
Theft Alarm
The ECM (Z132) has a simple on/off input regarding
the theft alarm. The ECM (Z132) will not allow the
engine to start once activated and will kill the engine
if activated up to 300 RPM (programmable). Over
300 RPM, the engine is unaffected.
Relays
The DDE engine management system on the diesel
vehicles uses four relays:
ECM (Z132) power supply (main relay), glow plug
relay, starter motor relay and fuel pump relay. Two
are located in the fuse box and two in the ECM
(Z132) box behind the battery. 
						

							DIESELA6
CIRCUIT OPERATION4
Main Relay
Located in the ECM (Z132) box, this relay supplies
the power feed to the ECM (Z132). It is controlled via
the Ignition Switch (X274) in position II.
Glow Plug Relay (Z135)
The Glow Plug Relay (Z135) takes a feed directly
from the battery and, on initialisation via the ECM
(Z132), supplies current to each of the six glow plugs
(one per cylinder) to aid cold starting. The glow time
is controlled via the ECM (Z132) which also monitors
the relay and illuminates the glow plug indicator lamp
for the duration of the glow time. This relay is
relatively large and is located with the main relay
next to the ECM (Z132).
Starter Motor Relay
This relay is also ignition key controlled, activated
with the key in the ignition III position only. Releasing
the key after cranking cuts supply to the relay and
switches off the starter motor.
Fuel Pump Relay
The fuel pump relay is pulled in when the starter
motor is activated, the earth path provided by the
alternator output. When the engine is running, the
starter motor is deactivated, supplying an earth path
while the generator supplies a feed i.e. a polarity
reversal.
ECM (Z132)
If the ECM (Z132) itself is not working, the entire
engine management system will cease to operate,
i.e. no fuel, tacho reading, etc. 
						

							DIESELA6
5CIRCUIT DIAGRAM
30
F 37
20 AP125a
Engine Compart-
ment Fuse Box
[13] A/C Con-
denser Fan
1 Relay
[14] A/C Con-
denser Fan
2 Relay
[15] Ignition
Relay
[18] A/C Control
Relay
[19] Engine
Main Con-
trol Relay
RL19
[19]
Not used
Shorting Link 5 2
RL15
[15]
5
2
13
RL18
[18]
3
15
4
RL14
[14]
5 C575
Not used 8 C1733 C5754 C176
30
F 26
20 A
8 C575
RL13
[13]
4
Z238
Body Electrical
Control Module
(BECM) 9 C120W
RWHeating and Ven-
tilation YB
S572
E574
A
A6-6
1 C587
2 C587K229
Solenoid Valve,
Injection Timing
Device
W
10 C572
Z132
Engine Control
Module (ECM)
17 16 44
B
A6-9
K217
Fuel Heater
1 C5923
2 C592
R
S571
B
See Ground
Distribution18
E574
See Ground
Distribution
19 C572
BB
2 
						

							DIESELA6
6CIRCUIT DIAGRAM
See Ground Dis-
tribution
A
A6-5
See Ground Dis-
tribution
C
A6-7
E574
F 0
80 A
RW
12 C584
1
9
2
8
3
7
4
3
5
2
6
1
S574
1165 C584
S571
E181
41 C572 8
Z132
Engine Control
Module (ECM) P104
BatteryZ135
Glow Plug Timer
Unit
See Power Dis-
tribution
GK1 GK2 GK3 GK4 GK5 GZS DIA 31
P120
Glow PlugsKL30 30ES
BG BP BY BR BWBN
B BR BY BN R
BGK6 
						

							DIESELA6
7CIRCUIT DIAGRAM
30
F 39
10 A
120 

S114
D
A6-8
See Ground Dis-
tributionZ238
Body Electrical
Control Module
(BECM)
C
A6-6
15 C114
D+
NY
S573
C571 C121
25
BN
2 C575 6Z106
Generator
1 C177 52
Shorting Link 2
E167 WO B
2 C172
4 C575
Not used
RL 12
[12] 31
Not used
15
52
RL 16
[16] 31
30
MF2
30 A
Not used
D1
D2D3
1 C5756 C177
NR WR
Starting and
Charging
P125a
Engine Compart-
ment Fuse Box
[12] Fuel Pump
Relay
[16] Starter
Relay 
						

							DIESELA6
8CIRCUIT DIAGRAM
2C114
M [1] [2]
Z134
Fuel Pump Module
[1] Fuel Level Sensor
[2] Fuel Pump
[1] 0
WP
2
3C111
WU
4C110 GBZ238
Body Electrical
Control Module
(BECM)
1
3C110 2
WO
D
A6-7
1C111
X135
Inertia Fuel
Shut±Off Switch
[1] Impact
See Ground Dis-
tribution
E167
10
42
PRZ132
Engine Control
Module (ECM)
27
16GR
Data Link Con-
nector
17C571
C121
KR
LG
K
Data Link Con-
nector
15 C10216
C202
LGR
KR
S2147 C231
S21315
LGR
LGR
X127
Data Link Con-
nectors3 C572
G
1 C582
K111
Fuel Shut±Off So-
lenoid