INFORMATION DOCUMENT

GENERAL
0.1. Make: Renault (DXi 13)

0.2. Type and commercial description: Engine type: D13

0.3. Means and location of identification
of type, if marked on the vehicle: N.A.
0.4. Category of vehicle (if applicable): N.A.
0.5. Category of engine: Diesel
0.6. Name and address of manufacturer: VOLVO POWERTRAIN CORPORATION
SE-405 08 GÖTEBORG
SWEDEN
0.7. Name and address of N.A.
manufacturer’s representative
0.8 Location of statutory plates and N.A.
inscriptions and method of affixing:
0.9. In the case of components and Self-adhesive decal placed on the valve cover or
separate technical units, location an approval mark is shown in the vehicle
and method of affixing of the EC instrument cluster.
approval mark:
0.10. Addresses of assembly plants: VOLVO POWERTRAIN CORPORATION
SE-541 87 Skövde
SWEDEN

VOLVO do Brasil Veículos Ltda

Caixa postal 7981
81260-900 Curitiba, PR
BRAZIL

0.11. In the case of a vehicle equipped

with an on-board diagnostic (OBD)
N.A.
system, written description and/or
drawing of the MI:

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 Annex 1
ESSENTIAL CHARACTERISTICS OF THE PARENT ENGINE AND THE ENGINE TYPE WITHIN THE
FAMILY AND INFORMATION CONCERNING THE CONDUCT OF TESTS
1 DESCRIPTION OF ENGINE

1.1. Make: Renault (DXi 13)

1.1.1. Name and address of VOLVO POWERTRAIN CORPORATION

manufacturer: SE-405 08 GÖTEBORG
SWEDEN

1.2. Manufacturer’s engine code: D13

Engine model
DXi 13 520KS EUV
DXi 13 520S EUV
DXi 13 480KS EUV
DXi 13 480S EUV
DXi 13 440KS EUV
DXi 13 440S EUV

1.3. Working principle: Compression ignition

Cycle: Four stroke

1.4. Number and arrangement of

cylinders: 6 in line

1.4.1. Bore: Ø 131 mm

1.4.2. Stroke: 158 mm

1.4.3. Firing order: 1-5-3-6-2-4

1.5. Cylinder capacity: 12.777 dm3 = 12777 cm 3

1.6. Volumetric compression ratio: 17.8:1 ± 1

1.7. Drawing(s) of combustion
chamber and piston crown: See attachment 2
1.8. Minimum cross-sectional area of Inlet port(s): 2 x 13.85 cm2
inlet and outlet ports: Outlet port(s): 2 x 12.57 cm2
1.9. Idling speed: 500 - 700 rpm
1.10. Maximum net power: Engine model Maximum net power
nominal peak
DXi 13 520KS EUV 390 kW at 1800 rpm
DXi 13 520S EUV 390 kW at 1800 rpm
DXi 13 480KS EUV 360 kW at 1800 rpm
DXi 13 480S EUV 360 kW at 1800 rpm
DXi 13 440KS EUV 330 kW at 1800 rpm
DXi 13 440S EUV 330 kW at 1800 rpm

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1.11. Maximum permitted engine speed: Maximum no load speed 2150±50 rpm
Maximum speed during exhaust brake 2300 rpm
1.12. Maximum net torque: Maximum net torque nominal
Engine model
peak
DXi 13 520KS EUV 2601 Nm at 1200 rpm
DXi 13 520S EUV 2601 Nm at 1200 rpm
DXi 13 480KS EUV 2448 Nm at 1200 rpm
DXi 13 480S EUV 2448 Nm at 1200 rpm
DXi 13 440KS EUV 2244 Nm at 1200 rpm
DXi 13 440S EUV 2244 Nm at 1200 rpm

1.13. Combustion system: Compression ignition

1.14. Fuel: Diesel

1.15. Cooling System

1.15.1. Liquid cooling Yes

1.15.1.1. Nature of liquid: Mixture of anti-freeze liquid and water

1.15.1.2. Circulating pump: Yes

1.15.1.3. Characteristics or make(s) and Make: Volvo

type(s) (if applicable): Type: Centrifugal

1.15.1.4. Drive ratio(s) (if applicable): engine - pump

D13: 1:1.76 with retarder,
1:1.41 without retarder

1.15.1.5 Thermostat; setting: Begins to open at: 82 ± 2°C

1.15.1.6 Radiator/fan system: description: Radiator:

Make(s): Volvo
Type(s): Tube and corrugation
Relief valve pressure setting: 75 kPa

Fan:
Make(s): BorgWarner or Behr
Type(s): EMS controlled with viscous clutch
Fan drive system: Viscous

1.15.1.7 Drive ratio (engine - fan): 1:1.33, 1:1.44

1.15.2 Air cooling N.A.

1.16. Temperatures Permitted by the

Manufacturer

1.16.1. Liquid cooling 110 ºC

Max. temperature at outlet:

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1.16.2. Air cooling; reference point: N.A.

1.16.3. Maximum temperature of the air at Air temperature rise < 16°C
the outlet of the intake intercooler: (Corresponds to a maximum temperature of the air at
the outlet of the intake intercooler of 41°C, when the
temperature of the inlet air is 25°C.)
1.16.4. Maximum exhaust temperature at
the point in the exhaust pipe(s)
adjacent to the outer flange(s) of
the exhaust manifold(s): 680°C
1.16.5. Fuel temperature (for diesel
engines at injection pump inlet): Max. 50°C
1.16.6. Fuel pressure (NG fuelled gas
engines only): N.A.
1.16.7. Lubricant temperature: Max. 125°C
Min. N.A.
1.17. Pressure Charger: Yes
1.17.1. Make: Holset
1.17.2. Type: Engine model: Type Volvo Part
No.:
HX55 or 21326115
DXi 13 520KS/520S EUV
HE500WG 23009845
21326115,
DXi 13 480KS/480S/440S HX55 or
21326118
EUV HE500WG
23009845

1.17.3. Description of the system (e.g. The engine is turbo-charged by an exhaust driven
max. charge pressure, wastegate, turbo charger with or without ECU controlled
if applicable): wastegate.

1.17.4. Intercooler: Yes

1.18. Intake System Engine model: Inlet system depression:

Maximum allowable intake DXi 13 520KS EUV 5.5 kPa
depression at rated engine speed DXi 13 520S EUV 4 kPa
and at 100 % load as specified in DXi 13 480KS EUV 5 kPa
and under the operating conditions DXi 13 480S EUV 3.5 kPa
of Regulation No. 24 and Directive DXi 13 440KS EUV 5 kPa
72/306/EEC as last amended by DXi 13 440S EUV 3.5 kPa
97/20/EC: (measurement at the gauge which indicates filter
exchange intervals)

1.18.1. Inlet manifold: See attachment 3

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1.18.2. Descriptions and drawings of air Air Filter:
intake system and its accessories. Make(s): Volvo or Donaldson
Type(s): Air cleaner with dry (paper) filtering media
See attachment 6

Intake silencer: None

1.19. Exhaust System Engine model: Exhaust backpressure:

Maximum allowable exhaust back DXi 13 520KS EUV 37.5 kPa
pressure at rated engine speed DXi 13 520S EUV 29 kPa
and at 100 % load as specified in DXi 13 480KS EUV 34.5 kPa
and under the operating conditions DXi 13 480S EUV 27 kPa
of Regulation No. 24 and Directive DXi 13 440KS EUV 30 kPa
72/306/EEC as last amended by DXi 13 440S EUV 24 kPa
97/20/EC: Exhaust pipe diameter: 123 mm
Static exhaust backpressure measurement at
reference point 1800 rpm

Exhaust system volume: 130 - 210 dm3

Exhaust manifold: See attachment 4

1.19.1 Description of exhaust equipment if N.A

the test is made with the complete
equipment provided by the engine
or vehicle manufacturer:

1.20. Engine Electronic Control Unit

(EECU):

1.20.1. Make: TRW

1.20.2. Type: Electronic Management System (EMS)

1.20.3 Software calibration number(s):

Engine model Software calibration nr

DXi 13 520KS EUV 21534845
DXi 13 520S EUV 21534844
DXi 13 480KS EUV 21534842
DXi 13 480S EUV 21534841
DXi 13 440KS EUV 22035799
DXi 13 440S EUV 21534839

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2 MEASURES TAKEN AGAINST
AIR POLLUTION

2.1. Device for recycling crankcase Closed crankcase ventilation / Crankcase ventilation
gases (description and drawing): open extended is optional

See attachment 5

2.2. Additional anti-pollution devices (if

any, and if not covered by another Function included in engine software, see Control
heading): Strategies Description, attachment 9

2.2.1. Catalytic Converter: Yes

2.2.1.1. Make(s): Renault (DXi 13)

2.2.1.2. Type(s): SCR (Selective Catalytic Reduction) and Clean-up

(Oxidation)

2.2.1.3. Number of catalytic converters 4 for the SCR and 2 for the Clean-up (integrated in
and elements: the rear two SCR stones)

2.2.1.4. Dimensions, shape and volume of SCR: Diameter: 9.5 inches per element
the catalytic converter(s): Length: 7.5 inches per element
Clean-up
coating: Length: 2.0 inches per element

2.2.1.5. Type of catalytic action: SCR: Selective Catalytic Reduction

Clean-up: Oxidation

2.2.1.6. Total charge of precious metals: SCR: 0 g

Clean up: 0.164 g

2.2.1.7. Relative concentration: SCR: None

Clean up: 1 g/ft3

2.2.1.8. Substrate (structure and material): Structure: Monolite; Material: Cordierite

2.2.1.9. Cell density: 400 CPSI (cells per square inch)

2.2.1.10. Type of casing for catalytic Expanding mat and metallic canning
converter(s):

2.2.1.11. Location of the catalytic Distance between turbine outlet and catalytic
converter(s) (place and reference converter inlet: 80-280 cm
distance in the exhaust line):

2.2.1.12. Normal operating temperature > 200°C

range:

2.2.1.13. Consumable reagents:

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2.2.1.13.1 Type and concentration of reagent 32.5 % by weight aqueous urea solution specified
needed for catalytic action: according to ISO 22241 / DIN 70070 and
manufactured from technically pure urea mixed with
desalinated water (AdBlue)

2.2.1.13.2. Normal operational temperature From –10°C to 70°C

range of reagent:

2.2.1.13.3. International standard (where ISO 22241 / DIN 70070

appropriate):

2.2.1.13.4. Frequency of reagent refill: Continuous

continuous/maintenance:

2.2.2. Oxygen Sensor: No

2.2.3. Air Injection: No

2.2.4. EGR: No

2.2.5. Particulate Trap: No

2.2.6. Other Systems: No

3 FUEL FEED

3.1. Diesel Engines

3.1.1. Feed pump

Characteristic pressure: 300-550 kPa

3.1.2. Injection System By fuel injection

Working principle: Direct injection

3.1.2.1. Fuel pump

3.1.2.1.1. Make(s): Delphi Diesel System

3.1.2.1.2. Type(s): Unit Injectors (E3), see attachment 7.

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3.1.2.1.3. Delivery: ...... mg per stroke on mg/stroke ± 4% at 1800rpm
engine at engine speed of ...... rpm See Annex 1 – Appendix 2 Item 2.1.1.
at full injection, or characteristic
diagram:

Mention the method used: On engine

If boost control is supplied, state

the characteristic fuel delivery and
boost pressure versus engine N.A.
speed

3.1.2.1.4. Injection advance

3.1.2.1.4.1 Injection advance curve: Included in engine software.

3.1.2.1.4.2 Static injection timing: N.A.

. See Control Strategies Description, attachment 9.

3.1.2.2. Injection piping

3.1.2.2.1. Length: N.A.

3.1.2.2.2. Internal diameter: N.A.

3.1.2.3. Injector(s)

3.1.2.3.1. Make(s): Delphi Diesel System

3.1.2.3.2. Type(s): Unit Injectors, E3

Engine model: Volvo Part No:
DXi 13 520KS/520S/480KS/480S/ 21340616
440KS 440S EUV 21569200

3.1.2.3.3. ‘Opening pressure’ or

characteristic diagram: Setting value, new injector: 26 +0.8-0 MPa

3.1.2.4. Governor

3.1.2.4.1. Make(s): N.A.

3.1.2.4.2. Type(s): N.A.

3.1.2.4.3. Speed at which cut-off starts under

full load: 1900 rpm

3.1.3. Cold Start System

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3.1.3.1. Make(s): Volvo

3.1.3.2. Type(s): See attachment 6

3.1.3.3. Description: See attachment 6

3.1.3.4. Auxiliary starting aid: Option; preheating

3.1.3.4.1. Make: Volvo

3.1.3.4.2. Type: Electric heater

3.1.3.4.3. Description: See attachment 6

For engine start description see Control Strategies
Description, attachment 9.

3.1.4. By carburettor(s) N.A.

3.2. Gas-fuelled Engines: N.A.

4 VALVE TIMING

4.1. Maximum lift of valves and angles Lift Opening Closing

of opening and closing in relation (mm) (°ATDC) (°ATDC)
to dead centres or equivalent data: Inlet valve: 13.1 343 569
Outlet valve VEB+
12.3 117 377
520/480/440hp
Outlet valve EPG
12.3 127 367
520/480/440hp

4.2. Reference and/or setting ranges: With cold engine and no valve clearance reference;
inlet valve on cylinder No. 1 has opened 1.6 ± 0.3
mm at 6°ATDC.

5 IGNITION SYSTEM (SPARK

IGNITION ENGINES ONLY): N.A.

6 LUBRICATION SYSTEM

6.1 Description of the system: Pressurized lubrication

6.1.1 Position of lubricant reservoir: On engine

6.1.2 Feed system:

Circulation pump Yes

6.2 Lubricating pump

6.2.1 Make: Volvo

6.2.2 Type: Gear pump

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6.3 Mixture with fuel No

6.3.1 Lubrication oil/fuel ratio N.A.

6.4 Oil cooler: Yes

6.4.1 Drawing(s) or make(s) and type(s) Make(s): Volvo

Type(s): Plate oil cooler, water cooled

7 ENGINE DRIVEN EQUIPMENT The engine shall be submitted for testing with the
auxiliaries needed for operating of the engine
(e.g. fan, water pump etc.), as specified in and
under the operating conditions of Regulation No.
24 and Directive 72/306/EEC as last amended by
97/20/EC.

7.1. Auxiliaries to be fitted for the test If it is impossible or inappropriate to install the
auxiliaries on the test bench, the power absorbed
by them shall be determined and subtracted from
the measured engine power over the whole
operating area of the test cycle(s).

7.2. Auxiliaries to be removed for the Auxiliaries needed only for the operation of the
test vehicle (e.g. air compressor, air-conditioning
system, etc.) shall be removed for the test. Where
the auxiliaries cannot be removed, the power
absorbed by them may be determined and added
to the measured engine power over the whole
operating area of the test cycle(s).

8 ADDITIONAL INFORMATION ON
TEST CONDITION

8.1. Lubricant Used

8.1.1. Make: Renault Diesel or other makes

8.1.2. Type: SAE 10W30

8.2. Engine-driven Equipment The power absorbed by the auxiliaries needs

(if applicable) only be determined:
– if auxiliaries needed for operating the
engine, are not fitted to the engine, and/or
– if auxiliaries not needed for operating the
engine, are fitted to the engine

8.2.1. Auxiliaries fitted during test: N.A.

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8.2.1.1. Auxiliaries not fitted during test: Alternator
Make: Bosch
Type: 28V 110A, option 28V 120A, 28V 150A

Fan, EMS controlled with viscous clutch

8.2.2. Power absorbed at various

indicated engine speeds:

Power absorbed (kW) at various engine speeds

Low High Speed Speed Speed Ref.
Equipment speed speed A B C speed
Idle
913 2100 1209 1506 1803 2041
rpm rpm rpm rpm rpm rpm
P(a)
Auxiliaries needed for
operating the engine (to be
0 0 0 0 0 0 0
subtracted from measured
engine power see item 7.1)
- fitted during test
P(b)
Auxiliaries not needed for
operating the engine (to be 0 0 0 0 0 0 0
added to measured engine
power see item 7.2)

8.3 Additional auxiliaries in operation

when test is conducted in vehicle: N.A.
8.4 Transmission
State moment of inertia of
combined flywheel and
transmission at condition when no
gear is engaged, or description,
make(s) and type(s) (for torque 2.72 - 3.89 kgm2
converter):
9 ENGINE PERFORMANCES FOR PARENT ENGINE
(declared by the manufacturer)
9.1. Engine speeds
Low speed (nlo): 913 rpm
High speed (nhi): 2100 rpm
for ESC and ELR cycles Idle: 600 rpm
for ETC cycle Reference speed: Speed A: 1209 rpm
Speed B: 1506 rpm
Speed C: 1803 rpm
Reference Speed (nref): 2041 rpm

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LIST OF ATTACHMENTS

Attachment 1 Illustrations of engine

Attachment 2 Combustion chamber view and Piston crown view

Attachment 3 Inlet manifold

Attachment 4 Exhaust manifold

Attachment 5 Closed crankcase ventilation

Attachment 6 Air intake system and Cold start system

Attachment 7a-b Fuel system

Attachment 8 Exhaust aftertreatment system

Attachment 9a-c Control Strategies Description

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 Attachment 1

Illustrations of DXi 13

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 Attachment 2
Combustion chamber view

Piston crown view

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 Attachment 3
Inlet manifold

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 Attachment 4
Exhaust manifold

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 Attachment 5.

Closed crankcase ventilation

Closed crankcase ventilation (CCV) is an option for the Volvo customer. When CCV is used the blow-by
gases are vented from the valve cover to the separator between the air filter and the inlet of the
turbocharger.

A rotating separator is used to separate oil from the blow-by gases. The rotor has a number of conical
discs, stacked on top of each other, where the separation takes place. The disc stack rotates at 7,000–
9,000 rpm and the centrifugal forces make the oil droplets separate from the gases. The oil is thrown off
the edges of the discs and onto the inside wall of the housing, from where it runs to a drain outlet back to
the sump.

The rotating cleaner is driven by the lubricant oil pressure. A separator drain feeds the drive oil back to the
sump.

Open extended crankcase ventilation means that the blow-by gases are vented from the valve cover to
the separator and thereafter vented to the atmosphere.

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 Attachment 6

Air Intake system.

The air intake system includes an air-cleaner of dry-filter type and an indicator light for air-cleaner. The
indicator light comes on when the starting key is at Drive and the engine is not running. As soon as the
engine starts, the light should go out. If it comes on at full throttle, the air cleaner filter insert is blocked and
it is time to change the filter.

Cold Start system

Starting heater
The standard version of engine is not equipped with a starting heater. However a starting heater is
available as an option. It heats the inlet air before entering the inlet manifold to reduce white smoke during
cold start at low temperatures.

The time for preheating and afterheating is depending on the ambient temperature. There is no preheating
at temperatures above 20 ºC. From 20 ºC the preheating is linearly ramped up to 25 sec at 12 ºC. At 12
ºC to 0 ºC the preheating is 25 sec and from 0 ºC it is linearly ramped up to 50 sec at -10 ºC. At lower
temperatures than –10 ºC the preheating is 50 sec. The same is valid for afterheating.

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 Attachment 7a.
Fuel system

The main components of the feed system and their pipe connections.

The fuel pump (1) draws fuel through the fuel tank unit strainer (2) via the engine control unit cooling
coil (3), the pre-filter (4), the fuel filter housing (5), and the distribution housing (6) to the suction side
of the feed pump.

From the feed pump, the fuel is forced via the fuel filter housing and main filter (7) to the longitudinal
channel (8) in the cylinder head, which supplies the unit injectors (9) with fuel. The overflow valve (10),
controls the feed pressure and the return fuel is led via the distribution housing to the suction side of the
pump.

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 Attachment 7b.
Unit injectors

Each unit is a combination of injection pump and injector. The plunge in the pump part is actuated by the
camshaft via rocker arms, and fuel from the pump part is fed directly to the injector. The unit injector has
a solenoid valve that is used to start and stop the injection of fuel into the combustion chamber. A two-
valve design makes it possible to vary injection pressure. The needle control valve makes fuel needle
opening pressure (NOP) freely adjustable.

The unit injectors are controlled by an electronic control unit mounted on the engine.

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 Attachment 8
Exhaust aftertreatment system

Selective Catalytic Reduction SCR muffler

Clean-up catalyst

SCR catalyst

Aftertreatment muffler, SCR

DXi 13 520KS/520S/ Part number
480KS/480S/ 440S EUV
horizontal outlet 20920705; 20920600; 7420920706
vertical outlet, L1E 20920707; 20920619; 7421065783
vertical outlet, L2 20920708; 20920622
lifted muffler behind cab 21383182; 7421065784

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 Attachment 9a
Control Strategies Description DXi 13

1. Technical concept of the DXi 13

1.1. Base engine
DXi 13 is a straight in line six cylinder engine with a displacement of 13 litres. The E3 injectors used
provides both NOP and pilot injection. The injectors provide improved combustion configuration, which
lowers noise, smoke and PM-emissions.

1.1.1. Sensor
The sensors used in the base engine are:
1. Water in fuel
2. Oil level/temperature
3. Fuel pressure
4. Fan speed
5. Coolant level
6. Coolant temperature
7. Boost pressure/temperature
8. Camshaft position
9. Air pressure and temperature
10. Flywheel position and engine speed
11. Oil pressure
12. Crankcase pressure (optional)

The EMS further receives input from additional sensors:

Ambient air temperature
Ambient air pressure

1.2. Exhaust aftertreatment

The aftertreatment system in the DXi 13 engine is based on the SCR technology. A urea solution that fulfils
ISO 22241 / DIN 70070 (example: AdBlue) is used to reduce NOx to N2 in SCR catalysts. Excess ammonia
is converted to N2 and H2O in integrated clean-up catalysts (two stones).

1.2.1. Sensors
The sensors used in the exhaust aftertreatment system are:
• Exhaust temperature sensor
• Urea temperature/level sensor
• NOx sensor (only used for OBD)
1.2.2. SCR
The SCR catalysts are placed inside the muffler. The UREA (NH2)2CO decomposes into ammonia (NH3)
and CO2 in the exhausts. For this to take place the catalyst temperature cannot be too low. To monitor the
exhaust temperature there is a temperature sensor in the exhaust pipe. In the SCR catalysts the ammonia
reduces NOx to N2 so that the products N2 and H2O are formed. The basic chemistry is: NH 3 + NO x → N 2 + H 2O

1.2.3. Clean-up catalyst

Inside the muffler, downstream of the SCR catalysts, two clean-up catalyst elements are placed. The
clean-up catalysts are oxidation catalysts that convert excess ammonia to N2 and H2O.

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 Attachment 9b
2. Normal conditions control strategies
The normal conditions control strategies are the basic control of the engine and comprises a wide range
of operating conditions. The NOx emissions are reduced using urea injection and the PM and smoke
emissions are controlled by the fuel injection timing advance and the use of variable NOP for the main fuel
injection.

2.1. Activation criteria - engine mode select

Three modes for emissions optimisation are used. There are three basic settings of maps used at different
engine conditions. The maps are:

• Static operation
• Dynamic operation
• Transient operation

The transition between the maps is done with percentage values as inputs to interpolations. There is a
percentage value for transition between static and dynamic operation. This percentage value is later used
in other functions to weight the output from different maps.

2.1.1. Static operation

The static mode is used for emission optimisation at steady state conditions, i.e. small load changes.

Transition to static mode

There are three transition criteria for transition to static mode.
1. During a set time period, the torque derivative has not been too high.
2. During a set time period, there has not been a too great torque change over a set
time interval.
3. During a set time period, the engine speed derivative has not been high.
If the three criteria are fulfilled the conditions are considered stable and a transition to static mode is
performed.

2.1.2. Dynamic operation

The dynamic mode is used for emission optimisation by reducing smoke and PM-emissions at moderate
load changes.

Transition to dynamic mode

There are three possible transition criteria for transition to dynamic mode.
1. The torque derivative is high.
2. The torque change during a set time interval is too great.
3. The engine speed derivative is high.
If one of the criteria is true the conditions are considered dynamic and transition to dynamic mode is
performed.

2.1.3. Transient operation

The transient mode is used for emissions optimisation at heavy load changes. During transient conditions
there can be lack of air as a result of turbo-lag. This means that there is a risk for high PM emissions. To
handle this problem the combustion parameters have to be adjusted to limit the PM emissions.

Transition to and from transient mode

The transition to and from transient mode is based on the smoke torque limit. The air to fuel ratio (AFR) is
calculated and when the AFR is close enough to a set minimum limit transient mode is used.

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 Attachment 9c
2.2. Torque and fuel limitations
To limit the smoke a minimum AFR limit is used. If the AFR falls to the minimum limit the engine torque is
reduced.
Isoflow function temporally limit fuel flow under high engines speeds conditions to minimize fuel
consumption and avoiding not efficient way of driving and unsafe driving habits. It is a way to help the
driver to accelerate the vehicle using partial load curve based on constant fuel delivery managed by pedal
control strategy. No emissions and OBD related maps will be changed or optimized with this function. Total
fuel flow is restored to vehicle operator through pedal kickdown if necessary.

2.3. Aftertreatment control

The basic control of the aftertreatment system consists of the calculation of base engine NOx (NOx-level
before aftertreatment system) produced by the engine and the amount of urea needed to reduce it. The
calculation of the base engine NOx is based on engine speed, torque, main fuel injection timing, pilot fuel
injection timing and NOP.

3. Special conditions control strategies

3.1. Engine start
During cranking, which is defined as an engine speed interval, a special calculation of the fuel injection
has to be performed. This is done to ensure a fast and safe engine start.

3.2. Low temperature operation

At low ambient air temperature and/or low coolant temperature some actions have to be taken. The fuel
injection timing has to be adjusted not to get high HC emissions or misfire. The urea injection is adjusted
not to get urea slip. At low catalyst temperatures the conversion efficiency is decreased and hence the
urea injection is lowered. The EPG (exhaust pressure governor) can be engaged to shorten the engine
warm-up period.

3.3. High ambient temperature operation

At very high ambient temperature the urea injection demand is slightly phased down to protect from urea
slip.

3.4. High altitude operation

As the ambient air pressure decreases (higher altitude) the turbo speed rises. Because of the lower
ambient air pressure there will be less oxygen going into the engine. Less oxygen slows down the heat
release and if the fuel injection timing is not advanced there will be more energy release to the exhausts,
resulting in higher exhaust gas temperature and higher turbine speed. To counteract these effects, the
injection timing will be advanced at high altitude. Tests have been performed to confirm emission fulfilment
up to 1000 meter. At even higher altitudes the torque has to be limited to protect the engine from the effects
of slower heat release. High exhaust gas temperature can also be the effect of high ambient air
temperature.

3.5. Engine speed limitations

Too high engine speed can cause engine damage. There is a function that limits the engine speed by
reducing the torque to protect from these conditions.

3.6. Vehicle acceleration control

Vehicle acceleration control is a function that limits torque demand temporarily under high acceleration
condition to minimize fuel consumption and engine noise. It is also used to avoid unsafe driving habits
under very light load conditions. The limitation is only in place for the short period when the vehicle
acceleration is above the threshold level. Full load curve performance will always be available to vehicle
operator through pedal kickdown if necessary.

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3.7. Engine protection
Extreme conditions can damage the engine or the aftertreatment system, therefore functions that protect
from these conditions are used. Actions taken to protect the engine from damage are for instance torque
derate, engine speed limitation and vehicle speed limitation.

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