Common rail diesel injection (CDI), function - GF07.16-P-0001OM

ENGINE 651.9 in MODEL 204 (except 204.9), 204.9 up to 5/31/12, 207, 218 

ENGINE 651.9 in MODEL 212 (except 212.098/298) Delphi 

Common rail diesel injection (CDI) - general 

The C  ommon Rail D  iesel Injection (CDI), in an electrical combination with the sensors and actuators of engine 651, creates the engine management "CR-DII" or on vehicles with code B03 (ECO start/stop function), the engine management "CR-DIII".

The short description "CR-DII" or "CR-DIII" means:

CR = Common Rail 

D = Delphi (manufacturer of the diesel injection system) 

II = 2nd generation 

III = 3rd generation 

The "common rail" is the line shared by all injectors for fuel delivery. The fuel upstream of the injection is stored in this common line. Therefore a common rail system is also called "storage injection". The entire engine management system is located in the CDI control unit (N3/9).

Sensor data are directly read in from the engine management and indirectly via the CAN network and actuate the control actuators as required. The individual functions and systems of the engine management are controlled and coordinated by the CDI control unit.

The following table provides a model and major assembly overview:

The engine management is subdivided into the following systems:

• Base functions 
• Engine system 
• Diesel injection system 
• Air control system 
• Exhaust system 

Base functions 

• Control unit diagnosis
• Fault memory
• OBD II (OBD II)
• Diagnosis via the C  ontrol A  rea N  etwork (CAN)
• CAN network
• Flash programming
• Variant coding
• Drive authorization system stage 3 (DAS 3)
• Torque coordination
• Thermal management
• Alternator interface
• Maximum speed limit
• Synchronization
• Load determination

Diagnosis

For diagnostic purposes, the fault codes of the engine management system can be read out and deleted using Xentry Diagnostics, and individual diagnostic functions can be specifically actuated.

CAN network

The CDI control unit exchanges data via the attached drive train CAN (CAN C) and chassis CAN (CAN E) (model 204, model 207/212/218 up to model year 14/YoM 13 facelift) or chassis CAN 1 (CAN E1) model 207/212/218 as of model year 14/YoM 13 facelift) with other control units which are integrated into the CAN network.

The CDI control unit also acts as the interface (gateway) between the CAN bus systems. The CDI control unit is furthermore connected to the drive LIN (LIN C1) and the drive train sensor CAN (CAN I) (model 212 except model 212.098, 212.298) and (model 207, 218 as of 01.09.14) and exchanges data via these.

Flash programming

The engine management in the CDI control unit is flashable, i.e. the entire software of the control unit can be exchanged (replaced) using Xentry Diagnostics. The software required for control unit programming can be found in the diagnostic system.

Variant coding

With variant coding the following vehicle versions and equipment can, for example, be coded using XENTRY Diagnostics:

• Vehicle model
• National version
• Exhaust variant
• Transmission version

Model 204.347

As of 1.9.12 the exhaust system SG-SOGE (N12) (with code P84 (Sport Edition)) is installed as special equipment. The drive train CAN serves as an interface between the exhaust system sound generator control unit and the CDI control unit.

Engine system 

• Starter relay actuation
• Throttle valve control
• Safety fuel shutoff
• Transmission overload protection
• Support of the Electronic Stability Program (ESP®)
• Electronic transmission control Assist (EGS)
• Support for fully integrated transmission control (VGS)
• Driving on torque limitation
• Anti-jerk control
• Suction fan actuation
• Alternator regulation
• Glow time control
• Control of the engine management start/stop function (with code B03 (ECO start/stop function))

Diesel injection system 

• Pre, main and post injection
• Idle speed control
• Smooth running control
• Limp-home function
• A/C rpm increase
• Deceleration fuel shutoff
• Rail pressure regulation
• Fuel pump controlling
• High-pressure pump control
• Altitude adaptation
• RPM limitation

Air control system 

• Exhaust gas recirculation (EGR)
• Boost pressure control
• Intake air throttling through intake port shutoff (EKAS)

Exhaust system 

• Catalytic converter heating
• Oxygen sensor heater controlling
• Exhaust aftertreatment, DPF regeneration (D  iesel P  articulate F  ilter) with code (474) Particulate filter)
• Exhaust aftertreatment, injection of the reduction agent AdBlue® (with code U42 (BlueTEC (SCR) diesel exhaust treatment)) (model 212.except model 212.098/298) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) and (with code 494 (USA version) as of 01.09.13 (model 212 except model 212.098/298) or (with code U77 (BlueTEC (SCR) diesel exhaust treatment)) as of 01.09.14

ENGINE 651.9 in MODEL 207, 218

with CODE U77 (Diesel Emission control BLUETEC (SCR))

ENGINE 651.9 in MODEL 212 (except 212.098/298)

with CODE U42 (BlueTEC diesel exhaust treatment (SCR))

with CODE U77 (Diesel Emission control BLUETEC (SCR))

Delphi

These vehicles fulfil the EU6 exhaust emissions standard and the USA-BIN5 exhaust emissions standard.

Engine 651 is characterized by the following components:

• 2 Balance shafts
• Gearwheel drive in combination with a chain drive on the flywheel side for driving the high-pressure pump, oil pump, balance shafts and both camshafts
• The oil pump integrated in the crankcase
• Oil spray nozzle shutoff valve (Y131) for controlling the oil spray nozzles for piston crown cooling
• Switchable coolant pump
• Exhaust gas recirculation (EGR) with coolant-cooled pre-cooler and EGR cooler with switchable bypass duct
• Cylinder head with 2-piece water jacket
• Rapid glowing system with glow output stage (N14/3)
• Load-level controlled preinjection and post injection

The following variants are offered:

• Engine 651.913/925.has fuel injectors (Y76) with magnetic technology, a venturi integrated in the high-pressure pump, a turbocharger with adjustable guide vanes and a boost pressure regulator (Y77/1)
• Engine 651.9 except 651.913/925.has fuel injectors with piezo-technology, two in series engaged turbochargers with a vacuum-controlled boost pressure control flap, the wastegate, a charge air bypass flap and an additional low-pressure turbocharger boost pressure sensor (B5/4)

The operating conditions of the engine and the associated active partial functions of the engine management are described in the following documents:

• Ignition ON, function 
• Starting, function 
• Ignition OFF, function 
• Fuel supply, function 
• Injection regulation, function 
• Rpm control, function 
• Alternator interface, function 
• Smooth running control, function 
• Thermal management, function 
• Torque coordination, function 
• Deceleration fuel shutoff, function 
• Engine limp-home mode, function 
• On-board diagnosis, function 
• Engine timing, start/stop function (with code B03 (ECO start/stop function)) 
• Forced induction, function 
• Exhaust treatment, function 
• Exhaust gas recirculation, function 
• Preheat, function