lock JAGUAR XF 2009 1.G AJ133 5.0L Engine Manual

Technical Training
NP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine 04/14/2009
3-9
Engine Management System

Engine Control Module

The aluminum ECM case has two large black electrical
connectors with red lock-levers. The label indicates an
engineering number with the format **** – 12B864 – **.
The dimensions of the ECM are 155 x 170 x 40mm
(6 x 6.7 x 1.6 in.). Diagnostics
Diagnostic Trouble Codes (DTCs) are listed in the Diag-
nosis and Testing section of the GTR WSM. Codes are
listed in numerical order and each entry has:
• A notes column to detail any care points relating to the failure
• An indication column. 2-trip MIL means that the failure must be detected on two subsequent drive
cycles for the MIL to illuminate. Any other lamp
indicator will be recorded in this column. There may
also be a message displayed on the instrument cluster
while the failure is being detected that is not detailed
in this document.
• A description of any default action the module undertakes in response to the detection of the failure
• A list of possible causes of the failure
• Which pin (if any) on the control module is associ- ated with the failure
• The DTC description
• Test conditions. Operating the vehicle as described in this column should result in the running of the moni-
tor relating to the DTC.

NOTE:

The operating conditions described have been
specified to ensure successful monitor operation is possi-
ble in most cases; however, the monitor may operate out-
side of these conditions.

NOTE:

Not all DTCs may be logged by all vehicle types.
NP10V8093

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04/14/2009 NP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine
Technical Training
Engine Coolant Temperature Sensor

Engine Management System

ENGINE COOLANT TEMPERATURE SENSOR
The engine coolant temperature (ECT) sensor is a nega-
tive temperature coefficient (NTC) thermistor, used to
monitor engine coolant temperature.
The ECT sensor is vital to the correct running of the
engine, as a richer mixture is required at lower block
temperatures for good quality starts and smooth running,
leaning off as the temperature rises to maintain emis-
sions and performance.
The sensor has a twist-lock design with a latch mecha-
nism, and is located at the rear of the engine in the water
crossover pipe, between the two heads.
Failure Modes
• Uses engine-off time and MAF for calculation
Failure Symptoms
• Poor cold and hot start
• Poor driveability
• Cooling fans on permanently
Sensor Resistance vs. Coolant Temperature
NOTE:
If the ECT sensor fails, the ECM uses a default
value. The electric fan control module is sent a default
coolant temperature value and switches the cooling
fan(s) on permanently.
The voltages shown represent the signal processed by
the ECM. When a defective coolant sensor is detected,
the coolant value defaults to 40°C (104°F) and remains
fixed until the ECM is powered down.
NP10V8099

Specification
Function
Supply voltage 5V ± 0.1V
Operating temperature range -30°C to 125°C
(-22°F – 257°F)
Pin 1 Sensor output signal
Pin 2 Sensor ground

Coolant Temperature
Approx. Resistance
-20°C (-4°F) 15.04 +0.90/-0.83 kOhms 20°C (68°F) 2.45 +0.10/-0.09 kOhms
80°C (176°F) 0.318 ±0.007 k Ohms
110°C (230°F) 0.1471 ±0.0018 k Ohms

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

3-2804/14/2009NP10-V8JLR: AJ133 5.0-Liter DFI V8 EngineTechnical Training
Fuel Tank Canister Purge ValveEngine Management System
FUEL TANK CANISTER PURGE VALVE
To comply with legislation in fuel evaporative loss, the evaporative emissions loss control system is used on all vehicles.
Its purpose is to minimize the evaporative loss of fuel vapor from the fuel system to the atmosphere. This is achieved by
venting the fuel system through a vapor trap – a canister filled with vapor-absorbing charcoal. The charcoal acts like a
sponge and stores the vapor until the canister is purged under the control of the ECM into the engine for combustion. The
carry-over system uses the DMTL system to check for fuel tank integrity.
The canister is connected with the intake manifold, after the throttle body, via a purge valve. This valve is opened and
closed according to a PWM signal from the ECM. The system does not work properly in the case of leakage or clog-
ging within the system or if the purge valve cannot be controlled.
The canister is purged by drawing clean air through the
charcoal, which carries the hydrocarbons into the engine
where they are combusted. To maintain driveability and
emission control, purging must be closely controlled as a
1% concentration of fuel vapor from the canister in the
air intake may shift the air/fuel ratio by as much as 20%.
Purging must be carried out at regular intervals to regen-
erate the charcoal, since the storage capacity is limited.
The purge function is alternated with the fuel metering
adaptation, as both cannot be active at the same time.
The ECM alters the PWM signal to the purge valve to con-
trol the rate of purging of the canister. The purging of the
canister is done in a controlled manner in order to maintain
the correct stoichiometric air/fuel mixture for the engine.
The ECM also ensures that the canister itself is purged
frequently enough to prevent fuel saturation of the char-
coal, which could lead to an excessive buildup of fuel
vapor (and vapor pressure) in the system, increasing the
likelihood of vapor leaks. Failure Modes
• Valve drive open circuit
• Short circuit to battery voltage or ground
• Valve/pipe work blocked
• Valve stuck open
• Pipe work leaking/disconnected
• Noisy valve
Failure Symptoms
• Engine may possibly stall on return to idle (if valve
stuck open)
• Poor idling quality (if valve stuck open)
• Fuel metering adaptations forced excessively rich if canister is clear with valve stuck open
• Fuel metering adaptations forced excessively lean if canister is saturated with valve stuck open
• Saturation of canister (if valve stuck closed)
PURGE VALVE
AIR FLOWS ENS OR
THROTTLE
FUEL TANK CARBON FILTER
INTAKE
MANIFOLD
NP10V8111

3-3004/14/2009NP10-V8JLR: AJ133 5.0-Liter DFI V8 EngineTechnical Training
Controller Area Network Engine Management System
CONTROLLER AREA NETWORK
The Controller Area Network (CAN) is a high-speed
serial interface for sharing dynamic signals between elec-
tronic control modules. CAN communications are ‘self-
checked’ for errors, and if an error is detected the message
is ignored by the receiving electronic control module.
Due to the high rate of information exchange, the system
has a high degree of latency. This allows for a high num-
ber of errors to be present without reducing the data
transfer rate. In practice, this is a very reliable system.
Each CAN message is transmitted by one electronic con-
trol module and received by all other electronic control
modules on the CAN bus. Each message contains a fixed
structure of signals. The data exchanged is used so that
each electronic control module does not need to have a
hardwired sensor for each input. The CAN message iden-
tifiers are arranged by a network tool, which can guarantee
that all messages meet their specified timing needs.
Signal Overview
The CAN communication system is a differential bus
using a twisted pair that is normally very reliable. If either
or both of the wires of the twisted pair CAN bus is open-
or short-circuited, a CAN time-out fault will occur.
Below is a list of additional electronic control modules that
the ECM will communicate with on the CAN network:
• Instrument cluster
• Steering angle sensor
•TCM
• Active rear locking differential, if equipped
• Adaptive cruise control
• Electronic parking brake
Failure Modes
• CAN bus wiring short circuit or open circuit
• Incompatible software and message versions