Jaguar X-Type Sedan and Estate (Wagon). Manual - part 445

DPF control software incorporated into the engine control module (ECM)
Differential pressure sensor

The DPF reduces the pollution generated by diesel vehicles by filtering soot particles out of the exhaust gases.

The DPF is located in the exhaust system, downstream of the catalytic converter. A major feature of the DPF is its ability for regeneration.
Regeneration is the burning of particulates trapped by the filter to prevent obstruction to the free flow of exhaust gasses. The regeneration
process takes place at calculated intervals and is not noticeable by the driver of the vehicle.

Regeneration is most important, since an overfilled filter can damage the engine through excessive exhaust back-pressure and can its self
be damaged or destroyed. The material trapped in the filter is in the most part carbon particles with some absorbed hydrocarbons.

Item

Part Number

Description

Front face showing alternate closed cells

Side view showing exhaust gas flow through the filter and particulate build up

Rear face showing alternate closed cells

The DPF uses a filter technology based on a filter with a catalytic coating. The DPF is made from silicon carbide housed in a steel container
and has excellent thermal shock resistance and thermal conductivity properties. The DPF is designed for the engine's operating requirements
to maintain the optimum back-pressure requirements.

The porous surface of the filter consists of hundreds of small parallel channels positioned in the longitudinal direction of the exhaust
system. Adjacent channels in the filter are alternately plugged at the end. This design forces the exhaust gasses to flow through the porous
filter walls, which act as the filter medium. Particulate matter, which are too big to pass through the porous surface are collected and stored
in the channels.

The collected particulate matter, if not removed, can create an obstruction to exhaust gas flow. The particles are removed by a regeneration
process, which incinerates the particles.

Two processes are used to regenerate the DPF, passive and active.

Passive Regeneration

Passive regeneration requires no special engine management intervention and occurs during normal engine operation. The passive
regeneration involves a slow conversion of the particulate matter deposited in the DPF into carbon dioxide. This process is active when the
DPF temperature reaches 250°C (482°F) and is a continuous process when the vehicle is being driven at higher engine loads and speeds.

During passive regeneration, only a portion of the particulate matter is converted into carbon dioxide. This is due to the chemical reaction
process, which is only effective within the normal operating temperature range of 250°C to 500°C (482°F to 932°F).

Above this temperature range the conversion efficiency of the particulates into carbon dioxide increases as the DPF temperature is raised.
These temperatures can only be achieved using the active regeneration process.

Active Regeneration

Active regeneration starts when the particulate loading of the DPF reaches a threshold as monitored or determined by the DPF control
software. The threshold calculation is based on driving style, distance traveled and back-pressure signals from the differential pressure
sensor.

Active regeneration generally occurs every 370 to 1250 miles (600 to 2000km) although this is dependant on how the vehicle is driven. For
example, if the vehicle is driven at low loads in urban traffic regularly, active regeneration will occur more often. This is due to the rapid
build-up of particulates in the DPF than if the vehicle is driven at high speeds when passive regeneration will have occurred.

The DPF software incorporates an additional trigger, which is used as backup for active regeneration. If active regeneration has not been
initiated by a back-pressure signal from the differential pressure sensor, regeneration is requested based on estimated cumulative
particulate emissions since the last active regeneration event.

Active regeneration of the DPF is commenced when the temperature of the DPF is increased to the combustion temperature of the particles.
The DPF temperature is raised by increasing the exhaust gas temperature. This is achieved by:

Retarding the main injection timing
Reducing intake boost pressure levels
Activation of the inlet throttle
Introducing post-injection of fuel after the pilot and main fuel injections have occurred.

Control of the post-injection is determined by the DPF software monitoring the signals from the two DPF temperature sensors to establish
the temperature of the DPF. Depending on the DPF temperature, the DPF software requests the ECM to perform either 1 or 2 post-injections
of fuel:

The first post-injection of fuel burns inside the cylinder, which increases the temperature of the exhaust gas
The second post-injection of fuel is injected late in the power stroke cycle. The fuel partly combusts in the cylinder, but some
un-burnt fuel also passes into the exhaust where it creates an exothermic event within the catalytic converter, further increasing the
temperature of the DPF

The active regeneration process takes approximately 20 minutes to complete. The first phase increases the DPF temperature to 200°C
(392°F). The second phase further increases the DPF temperature to 600°C (1112°F), which is the optimum temperature for particle
combustion. This temperature is then maintained for 15-20 minutes to ensure complete incineration of the particles within the DPF. The
incineration process converts the carbon particles to carbon dioxide and water.

The active regeneration temperature of the DPF is closely monitored by the DPF software to maintain a target temperature of 600°C
(1112°F) at the DPF inlet. The temperature control ensures that the temperatures do not exceed the operational limits of the turbocharger
and the catalytic converter. The turbocharger inlet temperature must not exceed 760°C (1400°F) and the catalytic converter brick
temperature must not exceed 800°C (1472°F) and the exit temperature must remain below 750°C (1382°F).

During the active regeneration process the following ECM controlled events occur:

The turbocharger is maintained in the fully open position. This minimizes heat transmission from the exhaust gas to the turbocharger
and reduces the rate of exhaust gas flow allowing optimum heating of the DPF. If the driver demands an increase in engine torque,
the turbocharger will respond by closing the vanes as necessary
The throttle is closed as this assists in increasing the exhaust gas temperature and reduces the rate of exhaust gas flow which has
the effect of reducing the time for the DPF to reach the optimum temperature
The exhaust gas re-circulation (EGR) valve is closed. The use of EGR decreases the exhaust gas temperature and therefore prevents
the optimum DPF temperature being achieved
The glow plugs are occasionally activated to provide additional heat to assist in raising the DPF temperature

If, due to vehicle usage and/or driving style, the active regeneration process cannot take place or is unable to regenerate the DPF, the
dealer can force regenerate the DPF. This is achieved by either driving the vehicle until the engine is at its normal operating temperature
and then driving for a further 20 minutes at speeds of not less than 30 mph (48 km/h) or by connecting the Jaguar approved diagnostic
system to the vehicle, which will perform an automated static regeneration procedure to clean the DPF.

Diesel Particulate Filter Control

The DPF requires constant monitoring to ensure that it is operating at its optimum efficiency and does not become blocked. The ECM
contains DPF software, which controls the monitoring and operation of the DPF system and also monitors other vehicle data to determine
regeneration periods and service intervals.

The DPF software can be divided into 3 separate control software modules; a DPF supervisor module, a DPF fuel management module and a
DPF air management module.

These 3 modules are controlled by a fourth software module known as the DPF co-ordinator module. The co-ordinator module manages the
operation of the other modules when an active regeneration is requested. The DPF supervisor module is a sub-system of the DPF
co-ordinator module.

DPF Fuel Management Module

The DPF fuel management module controls the following functions:

Timing and quantity of the 4 split injections per stroke (pilot, main and 2 post injections)
Injection pressure and the transition between the 3 different calibration levels of injection

The above functions are dependant on the condition of the catalytic converter and the DPF.

The controlled injection determines the required injection level in addition to measuring the activity of the catalytic converter and the DPF.
The fuel management calculates the quantity and timing for the 4-split injections, for each of the 3 calibration levels for injection pressure,
and also manages the transition between the levels.

The 2 post injections are required to separate the functionality of increasing in-cylinder gas temperatures and the production of
hydrocarbons. The first post injection is used to generate the higher in-cylinder gas temperature while simultaneously retaining the same
engine torque output produced during normal (non-regeneration) engine operation. The second post injection is used to generate
hydrocarbons by allowing un-burnt fuel into the catalytic converter without producing increased engine torque.

DPF Air Management Module

The DPF air management module controls the following functions:

EGR control
Turbocharger boost pressure control
Exhaust Air Fuel Ratio (AFR) control

During active regeneration, the EGR operation is disabled and the closed-loop activation of the turbocharger boost controller is calculated.
The air management module controls the air in the intake manifold to a predetermined level of pressure. This control is required to achieve
the correct in-cylinder conditions for stable and robust combustion of the post-injected fuel.

The module controls the exhaust AFR by actuating the EGR throttle.

DPF Co-ordinator Module

The DPF co-ordinator module reacts to a regeneration request from the supervisor module by initiating and co-ordinating the following DPF
regeneration requests:

EGR cut-off
Turbocharger boost pressure control
Engine load increase
Control of air pressure in the intake manifold
Fuel injection control

When the supervisor module issues a regeneration request, the co-ordinator module manages the change over to the regeneration specific
settings. The change over occurs during an accelerator pedal release manoeuver from the driver or after a calibrated waiting time.

Pressure Differential Sensor

Item

Part Number

Description

High pressure connection

Low pressure connection

Electrical connector

The differential pressure sensor is located in the engine compartment, on the lower RH side of the bulkhead. The sensor is located on 2
studs and secured with nuts.

The differential pressure sensor is used by the DPF software to monitor the condition of the DPF. Two pipe connections on the sensor are
connected by pipes to the inlet and outlet ends of the DPF. The pipes allow the sensor to measure the inlet and outlet pressures of the
DPF.

As the amount of particulates trapped by the DPF increases, the pressure at the inlet side of the DPF increases in comparison to the DPF
outlet. The DPF software uses this comparison, in conjunction with other data, to calculate the accumulated amount of trapped particulates.

By measuring the pressure difference between the DPF inlet and outlet and the DPF temperature, the DPF software can determine if the DPF
is becoming blocked and requires regeneration.

Differential Particulate Filter Temperature Sensors

Two temperature sensors are used in the DPF system. One is located in the catalyst inlet and the second sensor is located in the DPF inlet.

The sensors measure the temperature of exhaust gas exiting the turbocharger and before it passes through the DPF and provides the
information needed to calculate the DPF temperature.

The information is used, in conjunction with other data, to estimate the amount of accumulated particulates and to control the DPF
temperature.

Instrument Cluster Indications

When the engine is at it's normal operating temperature and the vehicle is driven at moderate speeds, 30 mph (48 km/h), or more, a
regeneration of the DPF takes place automatically. This means that the exhaust particles collected in the filter are burned away and the
filter is emptied.

For drivers who make regular short journeys at low speeds, it may not be possible to efficiently regenerate the DPF. In this case, the DPF
software will detect a blockage of the DPF from signals from the differential pressure sensor and will alert the driver by displaying a warning
message 'DPF FULL' in the message center, plus either a RED or AMBER warning lamp.

CAUTION: If the warning message with the RED warning lamp is displayed, a Jaguar dealer/authorized repairer must be contacted as

soon as possible before damage to the DPF occurs.

When the message is displayed with an AMBER priority warning lamp, regeneration is required.

CAUTION: If the vehicle continues to be driven with the AMBER warning lamp illuminated without regenerating the DPF, the RED

warning lamp will illuminate.

• NOTE: Once triggered, the warning lamp and message will remain on until the ignition is switched to the 'OFF' position. Even though
regeneration is still required, the warning lamp and message will only re-appear after 255 seconds of driving and sufficient pressure has
built up in the DPF.

For more information, refer to the Owners Handbook.

Diesel Particulate Filter Side Effects

The following section details some side effects caused by the active regeneration process.

Engine Oil Dilution

Engine oil dilution can occur due to small amounts of fuel entering the engine crankcase during the post-injection phases. This has made it
necessary to introduce a calculation based on driving style to reduce oil service intervals if necessary. The driver is alerted to the oil service
by a message in the instrument cluster.

The DPF software monitors the driving style, the frequency of the active regeneration and duration. Using this information a calculation can
be made on the engine oil dilution. When the DPF software calculates the engine oil dilution has reached a predetermined threshold (fuel
being 7% of engine oil volume) a service message is displayed in the instrument cluster.

Depending on driving style, some vehicles may require an oil service before the designated interval. If a service message is displayed, the
vehicle will be required have a full service and the service interval counter will be reset.

Fuel consumption

During the active regeneration process of the DPF, there will be an increase in fuel consumption. W hen active regeneration is operating,
there will be a 100% increase in fuel consumption.

Published: 11-May-2011

Exhaust System - Exhaust System

Diagnosis and Testing

Overview

For information on the description and operation of the diesel particulate filter (DPF) and catalytic converter systems:
REFER to:

Exhaust System

(309-00 Exhaust System, Description and Operation).

Inspection and verification

1. Verify the customer concern.

Confirm the illumination of any DPF warning lamps (red or amber) and any message center information.
Once the ignition is turned off, the warnings will disappear, but will reappear after 255 seconds of driving, or once sufficient
pressure has built up in the DPF.

2. Visually inspect for obvious mechanical or electrical faults.

Visual inspection

Mechanical

Electrical

Mufflers and pipes
Catalytic converter
Diesel particulate filter (DPF)
Exhaust gas recirculation (EGR) valve
Turbocharger

Exhaust gas temperature sensors
Injectors
Differential pressure sensor and circuits
Exhaust gas recirculation (EGR) valve and circuits
Turbocharger and circuits
Glow plugs
Engine control module (ECM)

3. If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next

step.

4. Use the approved diagnostic system or a scan tool to retrieve any diagnostic trouble codes (DTCs) before moving onto the

symptom chart or DTC index.

Make sure that all DTCs are cleared following rectification.

Symptom chart

Condition

Possible source

Action

Engine oil dilution

Fuel entering the
crankcase during
post-injection

Note that depending on driving style and use, some vehicles may require
engine oil changes at less than usual service intervals. Check the message
center and service history. Change the engine oil and reset the counter as
necessary.

Excessive fuel
consumption/poor
performance

Damaged/blocked exhaust
pipe and/or muffler(s)
Blocked catalytic
converter(s)

Inspect the exhaust system for damage. Disconnect the exhaust system from
the catalytic converter(s) and check for restricted flow. Remove the catalytic
converter(s) and inspect internally for damage. Install new components as
necessary.
REFER to:

Exhaust System

(309-00 Exhaust System, Description and

Operation).
Note that the fuel consumption increases while active regeneration is in
operation, but as this happens infrequently there is only a slight increase in
overall consumption.

Knocks/rattles from
underside

Exhaust system
components
insecure/damaged
Catalytic converter(s)
damaged

Inspect the exhaust system for damage. Check the security of the system
fittings. Tap the sides of the catalytic converter(s) with a soft-faced hammer
and listen for movement inside the converter. Install new components as
necessary.
REFER to:

Exhaust System

(309-00 Exhaust System, Description and

Operation).

Noise/fumes in vehicle

Exhaust system
components
insecure/damaged
Leakage from joints

Inspect the exhaust system for damage. Check the security of the system
fittings. In a well-ventilated area, close off the tailpipe(s) and check for
evidence of leakage. Seal any leaks as necessary.
REFER to:

Exhaust System

(309-00 Exhaust System, Description and

Operation).

DTC index

• NOTE: For a full list of Engine Control Module (ECM) DTCs:
REFER to:

Electronic Engine Controls

(303-14B Electronic Engine Controls - 2.0L Duratorq-TDCi/2.2L Duratorq-TDCi (110kW/150PS) - Puma,

Description and Operation).

DTC

Description

Possible cause

Action

P0544 Exhaust gas temperature sensor

circuit, right-hand bank, upstream
sensor

Exhaust gas temperature
sensor circuit: short circuit
to ground
Exhaust gas temperature
sensor circuit: open circuit
Exhaust gas temperature
sensor circuit: short circuit
to power
Exhaust gas temperature
sensor fault

Refer to the approved diagnostic system for a guided
diagnostic routine. Check the exhaust gas temperature sensor
and circuits. Refer to the electrical guides. Rectify as
necessary. Clear the DTCs, test for normal operation.

P0545 Exhaust gas temperature sensor

circuit low, right-hand bank,
upstream sensor

Exhaust gas temperature
sensor circuit: short circuit
to ground
Exhaust gas temperature
sensor circuit: open circuit
Exhaust gas temperature

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