Components common with the document: "Operating Principle - HDI direct injection system (High Pressure Diesel Direct Injection)"
Components common with the document
- Fuel high pressure common injection rail
- Battery (BB00)
- Engine speed sensor (1313)
- The camshaft position sensor (1115)
- Engine coolant temperature sensor (1220)
- Air temperature sensor (1310)
- Fuel temperature sensor (1221)
- Brake switch (2100)
Components common with the document: "Operating Principle - HDI direct injection system (High Pressure Diesel Direct Injection)" (BOSCH ECD15C2) - FAP system (particle filter)
Components common with the document
- Redundant brake pedal switch (7308)
- Clutch switch (7306)
- Vehicle speed sensor (according to vehicle)
Special parts
Features of the DW10BTED4 engine
- High pressure fuel pump
- Fuel flow actuator (1277)
- High pressure fuel regulator (1322)
- High pressure fuel sensor (1321)
- Accelerator pedal sensor (1261)
- Injection ECU (1320)
- Diesel injectors (1331,1332,1333,1334)
High pressure fuel pump
Role
Role of the high pressure fuel pump (SIEMENS DCP6199C-10/F type with 3 pistons)
- The pumping of the fuel (integral transfer pump)
- To supply high pressure fuel
- To supply the diesel injectors through the high pressure common injection rail
Description
(1) transfer pump (pre-supply)
(2) high pressure piston
(3) high pressure fuel regulator
(4) fuel flow actuator
(5) eccentric pump shaft
"a": fuel inlet (low pressure)
"b": high pressure fuel outlet (to the common injection rail)
"c": return to fuel tank
(1) transfer pump (pre-supply)
(2) high pressure piston
(3) high pressure fuel regulator
(4) fuel flow actuator
(6) pressure limiter
(7) lubricating valve
"a": fuel inlet (low pressure)
"b": high pressure fuel outlet (to the common injection rail)
"c": return to fuel tank
The high pressure fuel varies between 220 and 1500 bar
NoteThe high pressure fuel is controlled by the high pressure fuel regulator
NoteThe fuel flow entering the high pressure pump is controlled by the fuel flow actuator
Components mounted on the high pressure fuel pump
- High pressure fuel regulator (3)
- Fuel flow actuator (4)
NoteThe high pressure pump is not a distributing pump and does not need setting
The transfer pump (1) draws in fuel and delivers it to the following components (integral transfer pump)
- Lubricating valve (7)
- Fuel flow actuator (4)
When the fuel flow actuator is not energised
- The pressure limiter (6) opens
- The fuel is directed to the suction side of the transfer pump (1)
The lubricating valve (7) is used to lubricate the high pressure fuel pump
The fuel enters the fuel pump, passes through the lubricating valve (7) and returns to the tank (at "c")
Creating the high pressure
A: suction phase
B: delivery phase
(2) high pressure piston
(5) eccentric pump shaft
(8) fuel suction valve
(9) delivery ball valve
The shaft of the high pressure fuel pump contains a cam
The injection pistons are supplied with fuel by the low pressure circuit inside the high pressure pump
The fuel is drawn in by the piston during the suction phase
A - suction phase
- The fuel from the flow actuator "d" is drawn in through the suction valve (8)
- The return spring pushes the piston back against the cam
- The piston creates a vacuum in the liner (the delivery valve (9) closes)
B - delivery phase
- After bottom dead centre
- The fall in fuel pressure causes the suction valve to close (8)
- The fuel is blocked in the chamber
- The cam of the high pressure fuel pump pushes the piston
- The fuel pressure increases
- The fuel is delivered to the delivery valve
- The delivery valve (9) opens
After top dead centre, the delivery valve closes following the reduction in pressure
Transfer pump (pre-supply): role
Role of the transfer pump
- To pump the fuel from the tank
- To supply the high pressure fuel pump (it compresses the fuel upstream of the fuel flow actuator)
- To lubricate and cool the high pressure fuel pump
Transfer pump (pre-supply): description
Transfer pump with 5 vanes, protected by the fuel pressure limiter (6)
The fuel pressure limiter (6) directs the fuel to the suction side of the transfer pump (1), if the fuel flow actuator (4) is closed
WarningNo intervention is permitted on the high pressure fuel pump
Fuel flow actuator (1277)
Role
The fuel flow actuator
- Regulates the fuel flow drawn in by the high pressure fuel pump
- Admits the exact quantity of fuel required
- The transfer pump operates on reduced drive power compared to the BOSCH EDC15C2 system while still delivering the same quantity of fuel
The fuel flow is regulated by altering the cross section of the actuator nozzle
Description
C: fuel flow actuator not energised
D: fuel flow actuator energised
(10) spring
(11) socket
(12) piston
(13) electric coil
(14) magnetic core
"e": internal transfer pump supply
"f": fuel to the high pressure stage of the high pressure fuel pump (fuel high pressure circuit)
When the fuel flow actuator (4) is not energised
- The piston (12) is retained at the base of its location by means of the spring (10)
- The connection between the 2 pipes is closed
- The inlet to the high pressure stage of the high pressure fuel pump is closed
- The fuel is directed to the fuel pressure limiter (6), on the suction side of the transfer pump (1)
When the fuel flow actuator (4) is energised
- The coil (13) of the fuel flow actuator moves the magnetic core (14) (magnetic force)
- The piston (12) moves
- The connection between the 2 pipes is open
- The fuel is directed to the high pressure stage of the high pressure fuel pump
Electrical special features
The inlet to the high pressure fuel pump is closed when the fuel flow actuator is not controlled electrically
Control: injection ECU (earth)
Variable voltage control (OCR)
- Maximum voltage (OCR = 30%) = maximum fuel flow
- Minimum voltage (OCR = 0%) = zero fuel flow
Electrical features: resistance = 2,4 ohms
NoteOCR: opening cyclic ratio
High pressure fuel regulator (1322)
Role
The high pressure fuel regulator regulates the pressure of the fuel at the outlet of the high pressure fuel pump
Description
The high pressure regulator is identical to that of the DW10TD engine
E: high pressure regulator not energised
F: high pressure regulator energised
(15) valve seat
(16) ball
(17) needle
(18) electric coil
(19) magnetic core
(20) spring
"g": high pressure fuel circuit
"h": return to fuel tank
The fuel high pressure is regulated by modifying the rating of the high pressure fuel regulator
The high pressure fuel regulator consists of 2 pressure control circuits
- The electrical circuit which acts directly on the high pressure which controls the electromagnet of the high pressure fuel regulator (injection ECU)
- The mechanical circuit which provides a minimum pressure and dampens pulses
Mechanical operation
The high pressure fuel circuit is subject to pressure variations
The fuel high pressure increases when a pump piston delivers
The fuel high pressure decreases when a diesel injector is opened
The movement of the ball dampens pressure variations
Electrical operation
When the high pressure fuel regulator is not energised
- The fuel high pressure opposes the mechanical action of the spring (20)
- The regulator opens for a high pressure which is greater than the spring pressure (+50 bar)
- The fuel released by the high pressure regulator returns to tank through the outlet "h"
NoteEngine off for 30 seconds, there is no residual pressure in the high pressure fuel circuit
Pressure rise control phases
- The injection ECU supplies the high pressure fuel regulator with an OCR current
- The coil of the high pressure fuel regulator drives the magnetic core (magnetic force)
- The force applied to the ball is the sum of the spring force (20) and the magnetic force of the core
- The cut-out value of the high pressure regulator increases
Pressure reduction control phases
- The injection ECU reduces the OCR supplied to the coil of the high pressure fuel regulator
- The coil of the high pressure fuel regulator drives the magnetic core (magnetic force)
- The force applied to the ball reduces
- The cut-off valve of the high pressure regulator decreases
NoteOCR: opening cyclic ratio
Electrical special features
When the high pressure fuel regulator is not energised: the pressure is limited to +50 bars
Control: injection ECU (earth)
Variable voltage control (OCR)
- Maximum voltage (OCR = 30%) = maximum pressure
- Minimum voltage (OCR = 0%) = minimum pressure
Electrical features: resistance = 2,7 ohms
WarningAfter the engine has been switched off, wait 30 seconds before carrying out any work
Battery (BB00)
The charge level of the battery is important for the HDI direct injection system to operate
WarningA battery voltage of less than 7 volts disturbs the operation of the HDI direct injection system
The ECU memorises a fault in the following cases
- Battery voltage greater than 18 volts
- Battery voltage less than 6,5 volts
PSF1 injection double relay - special feature
The double relay is incorporated in the PSF1 unit
(21) double relay
High pressure fuel sensor (1321) - special feature
(22) high pressure fuel sensor
(23) metal gasket
Role
The sensor provides a voltage which is proportional to the fuel pressure in the high pressure common injection rail (50 to 1600 bars)
Description
Type 55P02-01
Electrical special features
Allocation of channels of connector
- Terminal 1: pressure information (0 to 5 volts)
- Terminal 2: earth
- Terminal 3: +5 volts supply
Voltage provided for a pressure of 300 bar: +1,2 Volts
Voltage provided for a pressure of 900 bar: +2,5 Volts
Engine speed sensor (1313)
Role
The sensor is used to work out the following parameters
- Engine rpm
- Position of removable coupling
Description
"Hall effect" sensor (DV type engine)
The sensor is opposite a target incorporated in the auxiliary equipment drive pulley hub (driven by the crankshaft)
The target has magnetic poles (60-2 pairs of poles)
The sensor supplies a square signal to the injection ECU each time a pair of poles passes it
The 58 poles make it possible to determine the engine speed
The 2 missing poles make it possible to determine the position of the crankshaft (no signal)
Recommendations
- Wash your hands before handling the hub
- Avoid any impact or damage to the magnetic track
- Use of sharp-edged tools is prohibited
- Keep magnetic tools away from the hub
- Do not rest on the magnetic target
- Do not bring force to bear on the target body
Electrical special features
Allocation of channels of connector
- Terminal 1: +5 volts supply
- Terminal 2: signal
- Terminal 3: earth
Location
(24) engine speed sensor
The sensor is located on the seal carrier plate, opposite a target incorporated in the auxiliary equipment pulley hub (timing side)
No setting is necessary
WarningThe sensor can be removed, WITHOUT removal of the auxiliary equipment drive pulley
The camshaft position sensor (1115)
Role
The role of the injection ECU in terms of the information received
- To synchronise fuel injections with respect to the position of the pistons
- To recognise top dead centres
Description
"Hall effect" sensor
(25) camshaft position sensor
(26) camshaft pulley
(27) rotor driven by the camshaft
(28) camshaft hub
(29) plastic lug
The camshaft sensor provides a square signal for the injection ECU
The camshaft sensor is located opposite a target driven by the camshaft pulley
The sensor is used to synchronise fuel injections with respect to piston position (sequential injection)
The plastic lug (29) is used to adjust the air gap in the factory
NoteThe plastic lug is destroyed the first time the engine is started
WarningWhen refitting a camshaft sensor, it is necessary to keep the gap between the sensors and target make VALEO: air gap 1 ± 0,5 mm
Comments: the check of the sensor consists of ensuring that its signal is correct and properly synchronised in relation to the engine speed/engine position sensor signal. moreover, each descending front of the camshaft target is located 20° before each TDC
WarningThe signal should be around 7 to 8 volts
Electrical special features
Supply: injection ECU
Allocation of channels of connector
- Terminal 1: 5 volts supply
- Terminal 2: signal
- Terminal 3: earth
The voltage slots are between 0 and 5 volts
Signal emitted
- Presence of metal earth opposite the sensor: 0 Volts
- Absence of metal earth opposite the sensor: 5 Volts
Accelerator pedal sensor (1261) - special feature: "point of resistance" sensor
In addition to the accelerator pedal sensor, the accelerator also has a "point of resistance" sensor (7316)
Role
The sensor is used for management of the speed limiter system
The role of the injection ECU in terms of the information received
If the point of resistance located at the end of the accelerator pedal travel is passed, the injection ECU authorises exceeding of the speed programmed by the driver (increases the fuel flow)
Description
(30) accelerator pedal point of resistance sensor
Electrical special features
2 way connector
Allocation of channels of connector
- Terminal 1: kick-down output signal
- Terminal 2: earth
Engine coolant temperature sensor (1220) - special feature
Role
The engine coolant temperature sensor informs the ECU about the engine coolant temperature
The role of the injection ECU in terms of the information received
- To adjust the pre-heating time
- To adjust the postheating time
- To adjust the starting flow
- Adjust the idling speed
- To authorise exhaust gas recycling (EGR)
- To adjust the fuel flow
- To limit the flow injected if the temperature of the coolant is critical (anti-boil function)
- To operate the fans
- To operate the logometer on the control panel (*)
- To operate the warning and prewarning lights (*)
Note(*) according to specification
Description
2-way green sensor
The sensor consists of a Negative Temperature Coefficient (NTC) resistor
The more the temperature increases, the more its resistance value is reduced
Electrical features: resistance at 20 °C = 6200 ohms
Location
The coolant temperature sensor (31) is located on the coolant housing on the bulkhead side
Plastic coolant outlet housing
- The coolant temperature sensor (31) is fixed by a plastic clip
- It is sealed with an O-ring
Injection ECU (1320)
Role
The ECU controls the whole injection system
The ECU software integrates
- Check functionalities of injection and pollution control
- Driving improvement strategies
- Engine immobiliser function
- Emergency strategies
- Fan unit and warning lamp operating management (*)
- The diagnostic with memorisation of failures
- The cruise control function (*)
Note(*) according to specification
The ECU ensures the electrical control of the following elements
- Diesel injectors
- High pressure fuel regulator
- Fuel flow actuator
- Recycling regulation electrovalve (EGR)
- Throttle control electrovalve (EGR)
- Pre and post-heating control unit (post-heating cut-off)
The ECU supplies the following information
- Engine speed: to the instrument panel
- Current consumption: to the on-board ECU
- Air conditioning cut-off
The atmospheric pressure sensor can not be separated from the injection ECU
The ECU contains a power stage which can supply the very high control current required for the diesel injectors to operate
The injection ECU software is updated by downloading (ECU fitted with a flash EPROM)
Description
(32) (1320) atmospheric pressure sensor
"j": connector CME (48-way grey)
"k": connector CMI (48-way brown)
"l": connector CH (32-way black)
The injection ECU is linked to the injection harness by 3 modular connectors
Connector assembly order
- Grey connector
- Brown connector
- Black connector
Allocation of channels of connector
Connector CME (48-way grey)
| channel No. | designation |
|---|---|
| A1 | NC (analogue air flow signal) |
| A2 | input: engine coolant temperature information |
| A3 | input: fuel temperature sensor |
| A4 | high pressure fuel sensor supply (5 volts) |
| B1 | input: turbocharger pressure |
| B2 | input: fuel pressure |
| B3 | high pressure fuel sensor earth |
| B4 | input: engine speed sensor signal |
| C1 | input: camshaft sensor signal |
| C2 | - |
| C3 | - |
| C4 | - |
| D1 | boost pressure sensor earth |
| D2 | - |
| D3 | - |
| D4 | camshaft sensor earth |
| E1 | - |
| E2 | boost pressure sensor supply |
| E3 | camshaft sensor supply (5 volts) |
| E4 | - |
| F1 | earth of the engine r.p.m sensor |
| F2 | - |
| F3 | input: engine oil pressure switch |
| F4 | supply: engine speed sensor |
| G1 | earth: engine coolant temperature sensor |
| G2 | - |
| G3 | - |
| G4 | - |
| H1 | - |
| H2 | input: water-in-fuel sensor |
| H3 | input: air flow signal (flow meter) |
| H4 | body earth |
| J1 | fuel temperature sensor earth |
| J2 | - |
| J3 | + battery after relay |
| J4 | body earth |
| K1 | oil level earth |
| K2 | + battery after relay |
| K3 | + battery after relay |
| K4 | body earth |
| L1 | output: injector No 2 control (out) |
| L2 | output: injector No 3 control (out) |
| L3 | output: injector No 1 control (out) |
| L4 | output: injector No 4 control (out) |
| M1 | output: injector No 4 control (in) |
| M2 | output: injector No 2 control (in) |
| M3 | output: injector No 1 control (in) |
| M4 | output: injector No 3 control (in) |
Connector CMI (48-way brown)
| channel No. | designation |
|---|---|
| A1 | input: tight spot sensor (speed limiter) |
| A2 | input: Air intake temperature sensor |
| A3 | - |
| A4 | - |
| B1 | - |
| B2 | input: differential pressure sensor |
| B3 | - |
| B4 | input: exhaust gas temperature sensor (downstream of the catalytic converter) |
| C1 | input: air temperature sensor (flow meter) |
| C2 | differential pressure sensor supply |
| C3 | EGR position sensor supply |
| C4 | input: turbo position copy sensor |
| D1 | supply: turbo position copy sensor |
| D2 | input: EGR position sensor |
| D3 | differential pressure sensor earth |
| D4 | pre-heat unit diagnostic line |
| E1 | output: pre/post heating relay |
| E2 | throttle housing position sensor earth (EGR) |
| E3 | - |
| E4 | turbo position copy sensor earth |
| F1 | - |
| F2 | - |
| F3 | point of resistance sensor earth (speed limiter) |
| F4 | - |
| G1 | output: coolant flow bypass electrovalve control |
| G2 | air flow meter temperature earth |
| G3 | intake air temperature earth |
| G4 | direct battery "+" |
| H1 | - |
| H2 | - |
| H3 | power relay |
| H4 | - |
| J1 | output: control of the coolant venting electrovalve |
| J2 | exhaust gas temperature sensor earth (downstream of the catalytic converter) |
| J3 | principal relay |
| J4 | - |
| K1 | - |
| K2 | body earth |
| K3 | - |
| K4 | - |
| L1 | - |
| L2 | output: EGR recycling electrovalve control (+) |
| L3 | output: control of the air/air heat exchanger bypass butterfly |
| L4 | output: fuel high pressure regulator (PCV) |
| M1 | output: control of the camshaft dephaser control electrovalve |
| M2 | output: EGR recycling electrovalve control (-) |
| M3 | output: throttle housing electrovalve control (EGR) |
| M4 | output: fuel flow actuator (VCV) |
Connector CH (32-way black)
| channel No. | designation |
|---|---|
| A1 | starter relay |
| A2 | - |
| A3 | dialogue line: CAN L network |
| A4 | dialogue line: CAN H network |
| B1 | output: control of additional heating 1 |
| B2 | output: control of fan unit group 1 (high speed) |
| B3 | - |
| B4 | line K diagnosis |
| C1 | output: control of additional heating 2 |
| C2 | input: accelerator pedal sensor N°2 |
| C3 | ignition plus / remotely controlled reawakening |
| C4 | cooling fan status |
| D1 | diagnostic line for the coils of the fan unit control relays |
| D2 | - |
| D3 | - |
| D4 | output: control of fan unit group 2 (low speed) |
| E1 | input: vehicle speed (vehicle speed sensor) |
| E2 | - |
| E3 | input: clutch switch |
| E4 | input: cruise control switch |
| F1 | - |
| F2 | air conditioning pressure sensor supply (5 volts) |
| F3 | - |
| F4 | air conditioning pressure sensor earth (5 volts) |
| G1 | - |
| G2 | supply of the accelerator pedal sensor (5 volts) |
| G3 | input: accelerator pedal sensor N°1 |
| G4 | body earth |
| H1 | - |
| H2 | air conditioning pressostat |
| H3 | earthing of pedal sensor |
| H4 | body earth |
Diesel injectors (1331,1332,1333,1334)
Role
The diesel injectors inject the amount of fuel required for the engine to operate
Injecting the fuel directly into the top of the pistons improves engine efficiency
The fuel can be injected in the following cases
- Pre-injection
- Main injection
- Post-injection
Description
(33) electrical connector
(34) laminar filter included in the connector (35) - (0,03 to 0,05 mm)
(35) high pressure fuel inlet connector
(36) diesel injector tip
(37) diesel injector needle
(38) pressure chamber
(39) diesel injector spring
(40) diesel injector needle control piston
(41) diesel injector needle spring
(42) closure cap
(43) opening control piston
(44) nut
(45) Piezoelectric control element
"m" return to fuel tank
The piezoelectric control element is located in the upper part of the diesel injector
The piezoelectric control element is secured to the body of the diesel injector by the nut (44)
The diesel injectors have 5 holes which encourage air/fuel mixing
NoteThe diameter of the 5 holes of the diesel injectors are suited to the engine version (0,16 mm Ø)
WarningDo not handle a diesel injector by means of its upper nut (44) (diesel injector will be damaged)
NoteThe laminar filter requires no maintenance
The amount of fuel injected depends on the following parameters
- Duration of the electrical control (injection ECU)
- Opening speed of the diesel injector
- Hydraulic flow of the diesel injector (number and diameter of holes)
- Fuel pressure in the fuel high pressure common injection rail
The fuel pressures used in the HDI direct injection system prevent the diesel injectors from being directly electrically controlled
The diesel injectors open due to the pressure difference between the control chamber (47) and the pressure chamber (38)
The diesel injector needle (37) is held against its seat by the spring (39)
The control piston (40) is fitted on top of the diesel injector needle (37) (the control piston is free within its bore)
The top of the control piston opens out into the control chamber (47)
The control chamber is connected to the following circuits
- High pressure fuel circuit through the nozzle (46)
- Fuel tank return circuit through the nozzle (48)
The control chamber (47) is isolated from the fuel return circuit by the opening control piston (42)
The diesel injector needle (37) is held against its seat by the spring (41)
The fuel is distributed evenly between chambers (38) and (47)
Nozzle (48) is larger than nozzle (46)
The opening control piston (43) moves as soon as the piezoelectric control element (45) is supplied
Lifting principle of a diesel injector
G: diesel injector closed
H: opening of a diesel injector
(41) diesel injector needle spring
(42) closure cap
(43) opening control piston
(45) Piezoelectric control element
(46) supply nozzle
(47) control chamber
(48) fuel return circuit nozzle
Diesel injector closed
The force exerted by the high pressure is the same between the control chamber (47) and the pressure chamber (38)
The control piston is locked (held against the diesel injector needle)
The rise in pressure in the fuel high pressure common injection rail encourages the diesel injector to close
H - opening principle of a diesel injector
The injection ECU supplies the piezoelectric control element
The current applied distorts the piezoelectric control element, which extends (0,004 mm)
The piezoelectric control element pushes on the opening control piston (43)
Operating phase when the opening control piston (43) moves
- A fuel leak is created through the nozzle (48)
- Fuel entering through the nozzle (46) does not compensate for the leak through the nozzle (48) - (Ø of nozzle (48) different to the Ø of nozzle (46))
- There is no longer a pressure balance between chambers (47) and (38)
- The pressure in the pressure chamber (38) lifts the diesel injector needle
- The control piston lifts up
- The fuel is sent to the top of the piston
The injection ECU interrupts the supply to the piezoelectric control element: the charging current stops the fuel capacitor remains charged
Piezoelectric control element remains extended
NoteFuel injection lasts for as long as the piezoelectric control element is not discharged
G - closing principle of a diesel injector
Operating phase when the injection ECU supplies the piezoelectric control element of the diesel injector (with a discharge current)
- The spring (41) holds the closure cap (42) against its seat
- The nozzle (48) is blocked
- The fuel leak to the return circuit stops
- The rise in pressure in the control chamber (47) causes the diesel injector to close
- The pressure balance is restored between chambers (47) and (38)
- The diesel injector is ready for a new cycle
Control of the diesel injectors (1331,1332,1333,1334)
Diesel injector control current
- T: duration
- I: amps
- U: Volts
- "i1": charge current
- "i2": discharge current
- "n": diesel injector closed
- "p": diesel injector open
The piezoelectric control element is controlled in 2 phases
- Charging phase of the piezoelectric control element (extension = opening)
- Discharging phase of the piezoelectric control element (retraction = closing)
Piezoelectric control element
- Consists of 250 layers
- Polarised
Features of the electrical control
Allocation of channels of connector
- Terminal 1: + polarity
- Terminal 2: - polarity
Electrical features
- Resistance = 200 000 ohms
- Capacity = 0,003 - 0,0038 farad
WarningGiven the presence of high voltages at the terminals of the ECU and diesel injectors, voltages should always be measured with the recommended equipment
WarningDo not supply a diesel injector with 12 volts (diesel injector will be damaged)
WarningInverting the polarity of the diesel injector control wires will destroy the piezoelectric control element (destructive retraction)
WarningDo not operate a diesel injector, outside the cylinder head, unless its body is connected to the vehicle's earth (risk of electrostatic discharge)
WarningIt is forbidden to disconnect a diesel injector while the engine is running (risk of damaging the engine)
WarningAvoid any introduction of liquid into the connector (malfunction of the diesel injector)
WarningThe exerting of a rotational force on the injector nozzle is prohibited (risk of destruction of the diesel injector)