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Gasoline Injection And Ignition System With Direct Injection, Function - GF07.70-P-0002MRH

Engine 274.9 in model 205.047/053/054/147/247/253 

Engine 274.9 in model 253.353/953 

Engine 274.9 in model 253.354/954 

G14547254Courtesy of MERCEDES-BENZ USA

Block diagram for networking of direct line, valid until facelift 

G14547255Courtesy of MERCEDES-BENZ USA

Block diagram for networking of direct line, valid from facelift 

G14547256Courtesy of MERCEDES-BENZ USA

Block diagram for CAN network, valid until facelift 

G14547257Courtesy of MERCEDES-BENZ USA

Block diagram for CAN network, valid from facelift 

Gasoline injection and ignition system with DI, general 

The gasoline injection and ignition system with direct injection in electrical combination with the sensors and actuators of Engine 274 (direct injection) forms the Engine management system "MED40". The short designation "MED40" stands for:

= otor

= lectronics

D = Direct injection

4 = 4 cylinder

0 = generation 0

The whole Engine management is contained in the ME-SFI control unit. Sensor data are directly read in from the Engine management and indirectly via the CAN network and actuate the control actuators as required. Here the individual functions and systems of the Engine management are controlled and coordinated by the ME-SFI control unit.

Sales designation Model Engine Transmission Engine management Notes
Model 205  - - - - -
C 350 205.047 274.920 722.995 MED40 Sedan
C 300 e 205.053 274.920 716.702 725.017 MED40 Sedan
C 300 e 205.054 274.920 725.047 MED40 4MATIC sedan
C 350 205.147 274.920 722.995 MED40 Sedan (long wheelbase)
C 350 205.247 274.920 722.995 MED40 Wagon
C 300 e 205.253 274.920 716.702 725.017 MED40 Wagon
Model 253  - - - - -
GLC 300 e 4MATIC 253.353 274.920 725.047 MED40 Coupe
GLC 350 e 4MATIC 253.353 274.920 725.047 MED40 Coupe
GLC 350 253.354 274.920 725.043 MED40 Coupe
GLC 300 e 4MATIC 253.953 274.920 725.047 MED40 Cross-country vehicle
GLC 350 e 4MATIC 253.953 274.920 725.047 MED40 Cross-country vehicle
GLC 350 253.954 274.920 724.268 725.043 MED40 Cross-country vehicle

The Engine management is subdivided into the following systems:

Basic functions 

IMPORTANT Diagnosis

For diagnostic purposes, the fault codes of the Engine management can be read out and deleted with XENTRY Diagnosis, and individual diagnostic functions can be actuated in a targeted manner.

IMPORTANT CAN network

The ME-SFI [ME] control unit exchanges data with other control units that are integrated in the CAN network via the connected drive train CAN and Engine CAN. The ME-SFI [ME] control unit also acts as the interface (gateway) between the two CAN bus systems.

IMPORTANT Control module programming

The Engine management in the ME-SFI [ME] control unit can be programmed, i.e. the entire control unit software can be exchanged (replaced) using XENTRY Diagnosis. The software required for control unit programming can be found on the diagnosis system software DVD.

IMPORTANT Transport mode

In transport mode various functions of the Engine management are limited. Further information are available in the energy management function. If the kilometer reading of the vehicle is more than 250 km, the "Transport mode" system status is deactivated automatically and can also no longer be reactivated using XENTRY Diagnosis.

IMPORTANT Variant coding

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

Engine system 

Hybrid drive system 

Fuel injection system 

Ignition system 

Exhaust system 

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

  Crankcase ventilation system, function   GF01.20-P-0001MRH
  Ignition ON, function   GF07.10-P-1000MRH 
  Starting, function   GF07.10-P-1001MRH 
  Ignition OFF, function   GF07.10-P-1002MRH 
  Fuel supply, function   GF07.10-P-1003MRH 
  Injection regulation, function   GF07.10-P-1004MRH 
  Ignition system function   GF07.10-P-1005MRH 
  Synchronize fuel injection and firing order function   GF07.10-P-1006MRH 
  Start, post-start phase and warm-up enrichment, function   GF07.10-P-1007MRH 
  RPM control, function   GF07.10-P-1008MRH 
  Lambda control, function   GF07.10-P-1010MRH 
  Smooth running control, function   GF07.10-P-1011MRH 
  Thermal management, function   GF07.10-P-1012MRH 
  Torque coordination, function   GF07.10-P-1013MRH 
  Overrun mode fuel shutoff, function   GF07.10-P-1014MRH 
  Knock control, function   GF07.10-P-1015MRH 
  Camshaft adjustment, function   GF07.10-P-1016MRH 
  Engine limp-home mode, function   GF07.10-P-1019MRH 
  On-board diagnosis, function   GF07.10-P-1020MRH 
  Engine timing start-stop function   GF07.10-P-1041MRH 
  Charging, function   GF09.00-P-2000MRH
  Exhaust treatment function   GF14.00-P-3000MRH
  Electronic accelerator function   GF30.20-P-3015MRH
  Refueling safety detection function Engine 274.9 in model 205.047/053/054/147/247/253 with code 494 (US version) Engine 274.9 in model 253.353/354/953/954 with code 494 (US version) GF47.00-P-1000MRH
  On-board refueling vapor recovery function Engine 274.9 in model 205.047/053/054/147/247/253 with code 494 (US version) Engine 274.9 in model 253.353/354/953/954 with code 494 (US version) GF47.10-P-3004MRH
  Purging function   GF47.30-P-3015MRH
  Purging system with leak test function Engine 274.9 in model 205.047/053/054/147/247/253 with code 494 (US version) Engine 274.9 in model 253.353/354/953/954 with code 494 (US version) GF47.30-P-3016MRH
  Overview of system components for gasoline injection and ignition system with direct injection   GF07.70-P-9998MRH