Page 1177 of 2490

Th
e engine management system provides optimum control of
the engine under all operating conditions using several
strategically placed sensors and any necessary actuators. Electronic engine control consists of:
engine
control module
throttle posi
tion sensor
engi
ne coolant temperature sensor
cam
shaft position sensor
c
rankshaft position sensor
mass air
flow sensor
intake air temper
ature sensor
kn
ock sensor
heat
ed oxygen sensor
Electronic Engine Control
Engine
Control Module (ECM)
The ECM incorporates a comprehensive monitoring and diagnostic capability including software variations to ensure system
compliance with the latest diagnostic and emissions legislation in different markets. The engine control module controls the
coil on plug ignition system, electronic fuel system, cr uise control and the electronic throttle control system.
The ECM responds to input signals received from sensors relating to engine operatin g conditions and provides output signals
to the appropriate actuators. These outp ut signals are based on the evaluated input signals which are compared with
calibrated data tables or maps held within th e ECM before the output signal is generated.
The ECM needs the following inputs to calibrate the engine properly:
cam
shaft position
It
em
Par
t Number
De
scription
1—Knock
sensor
2—Engine
coolant temperature sensor
3—Cranksh
aft position sensor
4—D
ownstream oxygen sensor
5—Upstream oxygen sensor
6—Camshaft position
sensor
P
arts List
engi
ne rpm
engi
ne coolant temperature
amount
of engine detonation
Page 1178 of 2490
Throttle Position (TP) Sensor
Location
P
arts List
sen
d
s the ECM a signal indica
ting throttle plate angle
is
the main input to the ECM from the driver
i
s
a dual Hall effect devi
ce mounted on the motor en d of the throttle body
Two additional sensors are attached to the throttle body to provide additional feedback to the ECM: a mechanical guard
position sensor and an accelerator pedal position sensor.
Cam s
haft Position (CMP) Sensor
sen
d
s the ECM a signal indicating camshaft po
sition for fuel synchronization purposes
is
a variable reluctance device mounted on bank 2 cylinder side face
generates a signal when the ri
ng
fitted to the bank 2 inlet
camshaft passes the sensor
Cranksha
ft Position (CKP) Sensor
i
s
a variable reluctance device
mounted on the engine oil pan
Ite
m
Par
t
Number
De
scr
iption
1—Acce
le
rator pedal and mechanic
al guard position sensors
2—Throttle
(blade)
position sensor
Page 1179 of 2490

generates a signal when th
e dr
ive plate passes the sensor
sen
ds the ECM signals indicating crankshaft position and engine speed
is e
ssential for calculating spark timing
En
gine Coolant Temperature (ECT) Sensor
sen
ds the ECM a signal indicating the temperature of the engine coolant
is a t
emperature dependent resistor with a negative temperature coefficient (resistance changes inversely with
respect to temperature) and is constantly monitored by the ECM
Intake Air Temperature (IAT) Sensor
is m
ounted in the same housing as the MA
F sensor but is not a serviceable item
sen
ds the ECM a signal indicating the temperature of the air entering the engine
is a t
emperature dependent resistor which has a negative
temperature coefficient (its resistance changes inversely
with respect to ambient temperature).
Knock S
ensor (KS)
is a pi
ezo-electric device which sends a signal
to the ECM indicating engine detonation
Between 700 and 6800 rpm, the ECM will retard individual cylinder ignition timing when detonation occurs while allowing
the other cylinders to continue operating normally.
During acceleration, at critical load and speed conditions, the ECM retards ignition timing to prevent the onset of detonation.
H
eated Oxygen Sensor (HO2S)
are
positioned upstream of the catalytic convertor
is equipped with
a heating element wh
ich improves the response time of the sensors during engine warm-up
h
as the ability to generate a voltage signal proportional to the oxygen content of the exhaust gases leaving the
engine
pr
ovides feedback information to the ECM used to calc
ulate fuel delivery and provide optimum gas emissions
Variable V
alve Timing (VVT) Solenoid
R
efer to section 303-01.
Page 1180 of 2490
is
of the 'hot-wire' type (the resistan
ce of the wire varies as incoming air passing over it has a cooling effect)
provides f
eedback to the ECM to perm
it monitoring of mass air flow
is NO
T serviceable, necessitating its renewal should a fault occur
Mass Air Flo
w (MAF) Sensor
Location
Page 1181 of 2490
P
arts List
It
em
Par
t Number
De
scription
1—PI032
VVT solenoid 2
2—PI027
KS 2
3—PI004
ECT sensor
4—PI026
KS 1
5—PI031
VVT solenoid 1
6—PI035
MAFS (on vehicle)
7—PI050
Generator
8—PI040
Oil pressure switch
9—PI018
to PI021 Bank 1 Ignition coils 1 to 4
PI022 to PI025 Bank 2 Ignition coils 1 to 4
10—PI006
Throttle valve position sensor
11—PI002 En
gine management harness (on vehicle)
12—PI001 En
gine management harness (on vehicle)
13—PI033
Throttle valve motor
14—PI034
EGR valve (where fitted)
15—PI015 CM
P sensor
16—PI042
Accelerator pedal and
mechanical guard sensors
17—PI007
to PI010 Bank 1 Injectors 1 to 4 PI011 to PI014 Bank 2 Injectors 1 to 4
18—PI037
Compressor lock
sensor (where fitted)
19—PI036
Compressor clutch
20—PI017 CK
P sensor
E
ngine Harness Connectors
Location
Page 1182 of 2490
Ite
m
Par
t
Number
De
scr
iption
1—Engine
management fuse box
2—Engine
control module (E
CM)
Circuit Diagrams (extracts only)
ECM Su
pply Voltage
Page 1183 of 2490
It
em
De
scription
1Mechanica
l guard
position sensor (potentiometer)
2Pedal demand sensors (pot
entiometers)
3Thro
ttle position sensor
4Engine
control
module (ECM)
5Throttl
e motor power relay
6EMS fuse box
7Throttl
e motor
T
hrottle Sensors and Control
Page 1184 of 2490
Ite
m
Part
Number
Descr
iption
1—Knock
sensors, banks 1 and 2
2—Engine
control module (E
CM)
Knock
Sensor