2009 JAGUAR XF sensor

Technical Training
NP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine 04/14/2009
3-15
Engine Management System

Knock Sensors

KNOCK SENSORS
The ECM uses active knock control, which serves to
prevent engine damaging pre-ignition or detonation
under all operating conditions, enabling the engine to
operate without additional safety margins.
The ECM uses 4 piezo-ceramic knock sensors to determine
the point at which a cylinder is pre-detonating. Two sensors
are mounted on the intake side of each cylinder head.
Each sensor monitors engine knock by converting the
engine block noise into a suitable electrical signal, which
is then transmitted back to the ECM via a twisted-pair
cable. The signal is processed within the ECM to iden-
tify the data that characterizes knocking.
This information is compared to known signal profiles to
determine whether pre-ignition is present. If so, the
closed loop control system retards the ignition on that
cylinder for a number of cycles, after which it gradually
moves back towards its original setting.
Safety Precautions CAUTION: Terminals in sensor and connec-
tor are gold plated for corrosion/temperature
resistance. Do not probe connections.
NOTE:
Accurate orientation of the knock sensors on the
cylinder block is required to ensure correct connection to
the vehicle wiring harness.
Failure Modes
• Sensor open circuit
• Short circuit to vehicle ground or battery voltage
• Faulty component or incorrectly torqued / coming loose
• Noise on vehicle 12V supply could look like knock signal causing knock fault
• Min fault usually due to open circuit
• Max fault short circuit to battery voltage or extreme mechanical engine noise/piston slap
• ECM calculates the default value if one sensor fails on each bank of cylinders
Failure Symptoms
• Knock control is disabled and a default ‘safe ignition map’ is used
• Possible rough running and reduced engine perfor- mance
Failure Mode Behaviors
• The vehicle control system constantly checks open circuit of knock sensor. Therefore, the knock sensor
is connected to the power source via pull-up line of
the ECM.
• When short/open circuit occurs to the knock sensor signal circuit, the system detects it, sets failure flag,
and commences maximum retard control on spark
advance.
• As far as the behavior of knock sensor is concerned, however, the above-mentioned failure modes cannot
cause serious outcomes such as heat generation,
smoke emission and/or fire hazard.
NP10V8100

Specification
Function
Power Source N/A
Wiring Type Twisted Pair
Shunt Resistance 4.8M Ohms
Operating Range 3kHz – 22kHz
Mounting Torque 20Nm +/- 3.8Nm

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04/14/2009 NP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine
Technical Training
Manifold Absolute Pressure Sensor

Engine Management System

MANIFOLD ABSOLUTE PRESSURE SENSOR
The manifold absolute pressure (MAP) sensor provides
a voltage proportional to the absolute pressure in the
intake manifold. This signal allows the load on the
engine to be calculated and used within the internal cal-
culations of the ECM.
The MAP sensor is mounted on the top of the engine, at
the front behind the throttle body. The purpose of the
sensor is to measure the absolute pressure in the intake
manifold and provide information to the ECM, which
will determine the injection time.
The sensor is a semi-conductor type, which responds to
pressure acting on a membrane within the sensor, alter-
ing the output voltage.
The sensor receives a 5V reference voltage and a ground
from the ECM and returns a signal of between 0.5 – 4.5V
to the ECM. A low pressure returns a low voltage signal to
the ECM and a high pressure returns a high voltage.
The MAP sensor detects quick pressure changes in the
intake manifold after the electronic throttle. The signal is
used in conjunction with the MAF sensor signal to calcu-
late the injection period. The ECM monitors the engine
MAP sensor for faults and can store fault related codes.
Failure Modes
• Sensor open circuit
• Short circuit to battery voltage or ground
• Intake air restricted
• Default value of 1 bar (14.5 psi)
Failure Symptoms
• Rough running
• Difficult starting
• Poor driveability
NP10V8101

Specification
Function
Power Source 5V ±0.25V
Pin 1 Power
Pin 2 Ground
Pin 3 Output Signal
Operating Range 13.3 kPa – 250 kPa

Technical Training
NP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine 04/14/2009
3-17
Engine Management System

Mass Air Flow Sensor

MASS AIR FLOW SENSOR
Mass air flow is determined by the cooling effect of
intake air passing over a ‘hot film’ element contained
within the device. The higher the air flow the greater the
cooling effect and the lower the electrical resistance of
the ‘hot film’ element. The ECM then uses this analog
signal from the mass air flow (MAF) sensor to calculate
the air mass flowing into the engine.
The measured air mass flow is used in determining the
fuel quantity to be injected in order to maintain the sto-
ichiometric air/fuel mixture required for correct opera-
tion of the engine and exhaust catalysts. Should the
device fail, there is a software backup strategy that will
be activated once a fault has been logged.
The intake air temperature (IAT) sensor is integrated into
the MAF sensor. The IAT sensor is an NTC thermistor,
meaning that the sensor resistance decreases as the sen-
sor temperature increases.
The sensor forms part of a voltage divider chain with an
additional resistor in the ECM. The voltage from this device
changes as the sensor resistance changes, thus relating the
air temperature to the voltage measured by the ECM.
Because the engine requires a twin air intake induction
system, there are two MAF sensors per vehicle.
Safety Precautions CAUTIONS:
• Component should not be dropped or han-dled roughly.
• Ensure that no contamination enters the device.
• Some terminals in MAF and connector are gold-plated for corrosion resistance – DO
NOT probe.
Failure Modes
• Sensor open circuit
• Short circuit to battery voltage or ground
• Contaminated/damaged sensor element
• Air leak after MAF sensor
• Intake air restricted
• Resistance in the harness, causing signal offset
• Damaged sensor element
Failure Symptoms
• During driving the engine rpm might dip (before recovering)
• Difficulty in starting or start/stall
• Poor throttle response/engine performance
• Emissions incorrect
• Lambda control and idle speed control halted
• MAF signal offset
NP10V8102
SpecificationFunction
Supply Voltage 8 – 14V
(rated supply voltage: 14V)
Pin A Output (Vg)
Pin B Ground for Output (Vg)
Pin C Power Source
Pin D IAT Sensor Ground
Pin E IAT Sensor Output

3-1804/14/2009NP10-V8JLR: AJ133 5.0-Liter DFI V8 EngineTechnical Training
Temperature/Manifold Absolute Pressure Sensor Engine Management System
TEMPERATURE AND MANIFOLD ABSOLUTE PRESSURE SENSOR
The temperature and manifold absolute pressure
(TMAP) sensor is used only on SC variants. The TMAP
sensor provides a voltage proportional to the absolute
pressure between the supercharger intercooler and the
intake valve and the air charge temperature. These sig-
nals allow the ECM to calculate the air charge density.
The TMAP sensor is mounted at the rear of the engine,
below the charge air cooler of the LH bank.
Failure Modes
• Sensor open circuit
• Short circuit to battery voltage or ground
• Intake air restricted
• Boosted air leak
SpecificationFunction
Pin 1 Pressure Output Signal
Pin 2 Supply Voltage
Pin 3 Temperature Signal
Pin 4 Ground
NP10V8103
Temperature Signal
Pressure Signal
TEMPERATURE (°C)
OUTPUT SIGNAL (V)
RES IS TANCE (
Ω) (thous ands)
NP10V8104
5
4.5 4
3.5
3
2.5 2
1.5 1
0
0.5
-50 50 0 1001500 200 400 600
800 1000 1200
NOMINAL VOLTAGE
MINIMUM RES
IS TANCE
NOMINAL RES IS TANCE
MAXIMUM RES IS TANCE
NP10V8114
0
0.4
4.65
5
0 20 300
NOMINAL VOLTAGE
MINIMUM RESIS TANCE

Technical TrainingNP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine04/14/20093-19
Engine Management SystemThrottle Position Sensor
THROTTLE POSITION SENSOR
The engine torque is regulated via an electronic throttle
body (‘drive-by-wire’ system), where an electronic pedal
assembly determines throttle opening.
The throttle position (TP) sensor is mounted in the inte-
grated cover plate on the throttle body assembly. The
throttle body assembly is mounted at the top front of the
engine, in a similar position for both NA and SC variants.
This value is input into the ECM and the throttle is
opened to the correct angle by means of an electric direct
current (DC) motor integrated into the throttle body.
Movement of the motor is achieved by changing the
PWM signal to the DC motor, allowing it to be operated
in both directions.
The dual-output TP sensor in the throttle body is used to
determine the position of the throttle blade and the rate
of change in its angle.
A software strategy within the ECM enables the throttle
position to be calibrated each ignition cycle. When the
ignition is turned ON, the ECM commands the throttle
to open and close fully, thus performing a self-test and
calibration, learning the position of the full closed hard
stop position.Safety Precautions
CAUTION: Terminals in sensor and connec-
tor are gold-plated for corrosion/temperature
resistance – DO NOT probe.
Failure Modes
• Sensor open circuit
• Short circuit to battery voltage or ground
• If signal failure occurs the ECM will enter a limp home mode where the maximum engine speed is
2000 rpm
• Signal offset
• Vacuum leak
Failure Symptoms
• Poor engine running and throttle response
• Limp home mode – maximum 2000 rpm
• Emission control failure
• No closed loop idle speed control
NP10V8105
SpecificationFunction
Supply voltage 5V ± 0.2 V
Supply current Max. 10 mA/1 output
Tolerance – closed position ±150 mV Tolerance – WOT position ±150 mV
Operating temperature range -40°C – 160°C
(-40°F – 320°F)
Pin 1 Throttle motor valve open:
direction +
Pin 2 Throttle motor valve open:
direction –
Pin 3 Position sensor output 2
(Gold)
Pin 4 Ground (Gold)
Pin 5 Position sensor output 1
(Gold)
Pin 6 Position sensor 5V supply
(Gold)

3-2004/14/2009NP10-V8JLR: AJ133 5.0-Liter DFI V8 EngineTechnical Training
Throttle Position SensorEngine Management System
Throttle Body Motor
The air mass flow through the throttle body is a function
of throttle angle, air temperature, air pressure before
throttle plate, and differential air pressure over the throt-
tle plate.
SpecificationFunction
Control signal 500Hz PWM
Resistance 1.2 Ohms
Normal operating voltage range 13.5 V to 14.2 V Tolerance – WOT position ±150 mV
Operating temperature range -40°C – 160°C
(-40°F – 320°F)

Technical TrainingNP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine04/14/20093-21
Engine Management SystemAccelerator Pedal Position Sensor
ACCELERATOR PEDAL POSITION SENSOR
The accelerator pedal position (APP) sensor provides a
pedal position signal to the ECM. The ECM uses this
information to actuate the damper motor in the elec-
tronic throttle assembly to move the throttle disc to the
correct angle in relation to the pedal position.
The APP sensor signals are checked for range and plau-
sibility. Two separate reference voltages are supplied to
the pedal. Should one sensor fail, the other is used as a
limp home input.
The accelerator pedal position (APP) sensor provides two
outputs. If the ECM detects a difference between the two
signals, a fault code is stored. The ECM will use the signal
with the lowest value for electronic throttle control.
PinFunction
Pin 1 5V 1
Pin 2 Demand 1
Pin 3 Ground 1
Pin 6 5V 2
Pin 5 Demand 2
Pin 4 Ground 2

3-2204/14/2009NP10-V8JLR: AJ133 5.0-Liter DFI V8 EngineTechnical Training
Heated Oxygen SensorsEngine Management System
HEATED OXYGEN SENSORS
The heated oxygen sensors monitor the level of oxygen
in the exhaust gases and are used to control the fuel/air
mixture. Positioning the sensors in the stream of exhaust
gasses from each bank enables the ECM to control the
fuel metering on each bank independently of the other,
allowing much closer control of the air/fuel ratio and cat-
alyst conversion efficiency.
There are four heated oxygen sensors per engine:
• One upstream Universal Heated Exhaust Gas Oxy-
gen (UHEGO) sensor per bank
• One downstream Heated Oxygen Sensor (HO2S) per bank.
NP10V8106
UPS TREAM
DOWNSTREAM
GAS FLOW
UPSTREAM
UHEGO
1st BRICK 2nd BRICK DOWNS
TREAM
HO2S
NP10V8107