Powertrain Management: Description and Operation
GF07.61-P-6000MMD Component Description For ME-SFI [ME] Control Unit
ENGINES 276.9 in MODEL 172.4
View of engine from front
N3/10 ME-SFI [ME] control unit
Location
The ME-SFI [ME] control unit is located on the left on engine.
Task
The ME-SFI [ME] control unit creates in an electrical combination with the sensors and actuators of engine 276 DE (Direct-Injection) the engine timing.
The following systems and functions are controlled and coordinated by the ME-SFI [ME] control unit according to input signals:
- Ignition system
- Fuel supply
- Injection control
- Electronic accelerator
- Diagnosis and fault storage
- Engine timing start stop function (for code (B03) ECO start/stop function)
- Drive authorization system and immobilizer
- Regulated camshaft adjustment
- Intake manifold switchover
- Heat management
- Torque interface
- Alternator interface
- Exhaust gas recirculation and exhaust treatment (with NOx catalytic converter)
Input and output signals
The following input signals are evaluated by the engine control and issued in the respective output signals:
^ Direct input signals
^ Direct output signals
^ LIN signals
^ CAN input signals
^ CAN output signals
Direct input signals
- Circuit 15
- Circuit 30 (fused)
- Circuit 31
- Circuit 87M4
- RH knock sensor (A16/1)
- LH knock sensor (A16/2)
- Hot film MAF sensor (B2/5) (for an engine with stratified operation)
- Intake air temperature sensor (B2/5b1) (on engine with stratified operation)
- Fuel tank pressure sensor (B4/3) (with code (494) USA version)
- Fuel pressure and temperature sensor (B4/25)
- LH intake camshaft Hall sensor (B6/4)
- RH intake camshaft Hall sensor (B6/5)
- LH exhaust camshaft Hall sensor (B6/6)
- RH exhaust camshaft Hall sensor (B6/7)
- Coolant temperature sensor (B11/4)
- Temperature sensor upstream of RH NOx storage catalytic converter (B16) (for an engine with stratified operation)
- Temperature sensor upstream of LH NOx storage catalytic converter (B16/1) (for an engine with stratified operation)
- Intake air temperature sensor (B17) (for an engine without stratified operation)
- Intake manifold intake air temperature sensor (B17/1)
- Pressure sensor downstream of throttle valve (B28/7) (intake manifold air pressure)
- Accelerator pedal sensor (B37) - potentiometer 1
- Accelerator pedal sensor - potentiometer 2
- Crankshaft Hall sensor (B70)
- Oxygen sensor upstream of catalytic converter (G3/3)
- Oxygen sensor upstream of catalytic converter (G3/4)
- Left oxygen sensor downstream of catalytic converter (G3/5)
- Right oxygen sensor downstream of CAT (G3/6)
- Throttle valve actual value potentiometer 1 (M16/6r1)
- Throttle valve actual value potentiometer 2 (M16/6r2)
- Circuit 15 relay (N10/1kJ)
- AGR - RH Hall sensor (M16/45b1) (for an engine with stratified operation)
- AGR - LH Hall sensor(M16/45b2) (for an engine with stratified operation)
- Crash signal from supplemental restraint system control unit (N2/10)
- Oil level check switch (S43)
Direct output signals
- Sensor voltages 1 and 2 (5 V) - engine plug
- Sensor voltages 1 and 2 (5 V) - vehicle plug
- Sensor grounds 1 and 2 - engine plug
- Sensor ground 1 - vehicle plug
- Accelerator pedal sensor - reference masses for potentiometer 1 and 2
- LH oxygen sensor upstream of catalytic converter - oxygen sensor heater
- RH oxygen sensor upstream of catalytic converter - oxygen sensor heater
- LH oxygen sensor downstream of catalytic converter - oxygen sensor heater
- RH oxygen sensor downstream of catalytic converter - oxygen sensor heater
- Fan motor for combustion engine and air conditioning system with integrated control (M4/7) - specified fan speed
- Throttle valve - actuator motor (M16/6m1) (Plus)
- Throttle valve - actuator motor (M16/6m1) (Minus)
- Right exhaust gas recirculation actuator motor (M16/45m1) (on engine with stratified operation)
- Left exhaust gas recirculation actuator motor (M16/45m2) (on engine with stratified operation)
- Circuit 50 starter relay (N10/1kM)
- Engine circuit 87 relay (N10/1kN)
- Fuel pump control unit (N118) - "fuel pump ON" ground signal
- Coolant thermostat heating element (R48)
- Cylinder 1 ignition coil (T1/1)
- Cylinder 2 ignition coil (T1/2)
- Cylinder 3 ignition coil (T1/3)
- Cylinder 4 ignition coil (T1/4)
- Cylinder 5 ignition coil (T1/5)
- Cylinder 6 ignition coil (T1/6)
- LH intake camshaft solenoid (Y49/4)
- RH intake camshaft solenoid (Y49/5)
- LH exhaust camshaft solenoid (Y49/6)
- RH exhaust camshaft solenoid (Y49/7)
- Purge control valve (Y58/1)
- Activated charcoal canister shutoff valve (Y58/4) (with code (494) USA version)
- Cylinder 1 fuel injector (Y76/1)
- Cylinder 2 fuel injector (Y76/2)
- Cylinder 3 fuel injector (Y76/3)
- Cylinder 4 fuel injector (Y76/4)
- Cylinder 5 fuel injector (Y76/5)
- Cylinder 6 fuel injector (Y76/6)
- Intake manifold resonance flap switchover valve (Y77/2)
- Intake manifold selector drum switchover valve (Y77/3)
- Quantity control valve (Y94)
- Engine oil pump valve (Y130)
LIN signals
- Alternator interface via drive LIN (LIN C1)
- Cooler sensor for engine diagnosis (B11/15) via drivetrain LIN (for code (494) USA version and code (917) Partial zero emission vehicle-emission USA)
CAN input signals
Instrument cluster (A1)
- Fuel reserve signal
Supplemental Restraint System control unit (N2/10)
- Crash signal
- Driver seat belt applied
- Engine hood closed (for code (U60) Pedestrian protection)
Rear SAM control unit with fuse and relay module (N10/2)
- Engine hood closed (for code (551) Antitheft alarm system (EDW)
Automatic air conditioning control and operating unit (N22/7)
- Specified fan speed request
- Air conditioning status
- Engine torque request
- Engine start request
- Engine stop prohibition
Electronic Stability Program control unit (N30/4)
- Vehicle speed
- Wheel speed signal
- Brake recognition
- Cruise control request
- Engine torque request (increase)
- Engine torque request (reduction)
- Engine start request
- Engine stop prohibition
- Engine stop release
LH and RH NOx sensor control units (N37/1, N37/2) (on engine with stratified operation)
- NOx concentration in the exhaust
- O2 concentration in the exhaust
- Diagnostic data
Radar sensors control unit (N62/1) with code (233) DISTRONIC PLUS)
- Engine torque request (increase)
- Engine torque request (reduction)
Left door control unit (N69/1)
- Driver door closed
Upper control panel control unit (N72/1)
- ECO start/stop function status button
Electronic ignition lock control unit (N73)
- Start enable (drive authorization system)
Steering column module control unit (N80)
- Steering wheel angle
- Steering wheel angular velocity
Fuel system control unit (N118)
- Fuel pressure
- Self-diagnosis data
- Requested diagnostic data
Fully integrated transmission controller unit (Y3/8)
- Drive position
- Transmission mode
- Actual gear, target gear
- Engine torque reduction request
- Starter enable in selector lever position "P, N"
- Engine idle specified speed (for actuation of the torque converter lockup clutch)
- Status of torque converter lockup clutch
- Emergency transmission limp-home mode
- Transmission oil temperature
CAN output signals
Instrument cluster
- Engine oil level too low
- Circuit 61 signal (generated by ME-SFI [ME] control unit)
- Fuel consumption (the trip computer is informed about the current fuel consumption by means of square-wave pulse packages (1 pulse = 0.2 l/h))
LH and RH NOx sensor control units (on engine with stratified operation)
- Diagnosis request
Fuel pump control unit
- Fuel pump ON
- Specified fuel pressure
- Diagnosis request
Electronic ignition switch control unit
- Start enable request (drive authorization system)
Fully integrated transmission control control unit
- Requests for catalytic converter heating
- Switching request
- Engine torque
- Engine coolant temperature
- Engine oil temperature
- Engine speed
- Engine load
- Kickdown
- Engine speed limitation active
- Limp-home mode engine control
Design
The housing of the ME-SFI [ME] control unit is made out of diecast aluminum and the cover is made out of corrosion-proof sheet steel. The ME-SFI [ME] control unit is protected against water and dusts.
The housing contains the 32-bit measuring and control electronics for the engine control.
Power supply
The ME-SFI [ME] control unit is "circuit 30 fused" and also supplied with a voltage for ignition ON by "circuit 87 M4".
In the operating voltage range it has both short-circuit protection and reversed polarity protection.
Voltage is supplied through several pins connected in parallel to relieve the electrical connectors.
Ground connection
The "circuit 31" ground connection is made via several ground lines to the left major assembly compartment electronics ground point (W16/5).
Computer run-on
If the ME-SFI [ME] control unit receives the signal "circuit 15 OFF", a processor run-on of approx. 4 seconds is started.
However, it may also last for several minutes due to various functions (for example, on-board diagnosis (OBD), drive authorization system (DAS), thermal management).
Assembly operations
Ensure before unplugging the plug on the ME-SFI [ME] control unit that the ignition is switched off and computer run-on has ended. This is to prevent damage to the ME-SFI [ME] control unit and save errors in the control units linked to the CAN.
Variants
The engine control variants (e.g. national and exhaust variants) are activated with Xentry Diagnostics using the variant coding function. Replacement of the ME-SFI [ME] control unit is not necessary.
