S07.61-4531-08
N3/34 | ME-SFI [ME] control unit |
Location
The ME-MFI [ME] control unit (N3/34) is located on the left on the engine next to the charge air distributor.
Task
The ME-SFI [ME] control unit (N3/34) fulfills the following tasks:
Controlling the engine basic functions
Reading in of signals
Evaluation of signals
Output of signals and actuation of assembly parts
The ME-SFI [ME] control unit (N334) also serves as the interface between the chassis CAN (CAN E) and drive train CAN (CAN C).
Controlling the engine basic functions
Crankcase ventilation system
Start
Fuel supply
Injection control
Ignition system
Synchronization of injection and firing order
Start, post-start phase and warm-up enrichment
Rpm control
Alternator interface
Lambda control
Smooth running control
Thermal management
Torque coordination
Deceleration fuel shutoff
Knock control
Camshaft adjustment
Engine limp-home mode
European On-Board Diagnosis
Engine management ECO start/stop function
Charging
Exhaust treatment
Electronic accelerator
Purging
Reading in of signals
Signals are read in via the following connections:
Direct line
Drivetrain-LIN (LIN C3)
Drive train CAN (CAN C)
Chassis CAN (CAN E)
Evaluation of signals
The read in signals are evaluated by the integral microprocessor, and the relevant assembly parts are actuated.
Output of signals and actuation of assembly parts
Signals are read in via the following connections:
Direct line
Drivetrain-LIN (LIN C3)
Drive train CAN (CAN C)
Chassis CAN (CAN E)
The signals from the following assembly parts are sent or received from ME-MFI [ME] control unit (N3/34) over the direct lines:
Incoming signals over the direct line from: | Outgoing signals over the direct line to: | |
Knock sensor 1 (A16/8) | - | |
Knock sensor 2 (A16/9) | - | |
Fuel pressure and temperature sensor (B4/21) | - | |
Pressure sensor upstream of throttle valve (B5/13) | - | |
Intake camshaft Hall sensor (B6/29) | - | |
Exhaust camshaft Hall sensor (B6/30) | - | |
Coolant temperature sensor (B11/21) | - | |
Charge air temperature sensor upstream of throttle valve (B17) | - | |
Charge air temperature sensor downstream of throttle valve (B17/16) | - | |
Pressure sensor downstream of air filter (B18/8) | - | |
Intake manifold pressure sensor (B28/24) | - | |
Accelerator pedal module (B37/4) | - | |
Crankshaft Hall sensor (B70/2) | - | |
- | Wide open throttle operation vent line heater element (B157) | |
Purging pressure sensor (B158) | - | |
Tank pressure sensor (B172) (without code ZL3 (National version for Latin America)) | - | |
Oxygen sensor sensor element downstream of catalytic converter (G3/21b1) | - | |
- | Oxygen sensor heater downstream of catalytic converter (G3/21r1) | |
Oxygen sensor sensor element upstream of catalytic converter (G8/6b1) | - | |
- | Oxygen sensor heater upstream of catalytic converter (G8/6r1) | |
Engine compartment fuse and relay module (K40/10) | - | |
Circuit 15 relay (K40/10kR) | - | |
- | Circuit 50 starter relay (K40/10kM) | |
Circuit 87M relay (K40/10kN) | Circuit 87M relay (K40/10kN) | |
Actual value potentiometer 1 (M16/50r1), throttle valve | - | |
Actual value potentiometer 2 (M16/50r2), throttle valve | - | |
- | Throttle valve actuator motor (M16/50m1) | |
Supplemental Restraint System control unit (SRS) (N2/18) (without code ZL3 (National version for Latin America)) | - | |
Signal acquisition and actuation module (SAM) control unit (N10/1) | - | |
- | Fuel system control unit (FSCU) (N118) | |
- | Thermostat heating element (R48/4) | |
Oil level check switch (S43/5) | - | |
Vent line contact switch (S208) | - | |
- | Ignition coils (T1) | |
- | Coolant pump switchover valve (Y19/11) | |
- | Intake camshaft solenoid (Y49/10) | |
- | Exhaust camshaft solenoid (Y49/11) | |
- | Activated charcoal canister shutoff valve (Y57) (without code ZL3 (National version for Latin America)) | |
- | Purging switchover valve (Y58/7) | |
- | Fuel injectors (Y62) | |
- | Boost pressure control pressure transducer (Y77/10) | |
- | Quantity control valve (Y94) | |
- | Deceleration air switchover valve (Y101) | |
- | Partial load operation crankcase ventilation system valve (Y136) | |
- | Engine oil pump valve (Y138) |
The signals from the following assembly parts are sent or received from ME-MFI [ME] control unit (N3/34) over the drivetrain LIN (LIN (C3):
Incoming signals via the drivetrain LIN (LIN C3) from: | Outgoing signals via the drivetrain LIN (LIN C3) from: | |
Alternator (G2) | Alternator (G2) | |
Electric fan (M91) | Electric fan (M91) |
The signals from the following assembly parts are sent or received from ME-MFI [ME] control unit (N3/34) via the drive train CAN (CAN C):
Incoming signals via the drive train CAN (CAN C) from: | Outgoing signal via the drive train CAN (CAN C) to: | |
Fully integrated transmission control unit (VGS) (N15/11n4) (with A/T) | Fully integrated transmission control unit (VGS) (N15/11n4) (with A/T) | |
Fuel system control unit (FSCU) (N118) | Fuel system control unit (FSCU) (N118) |
The signals from the following assembly parts are sent or received from ME-MFI [ME] control unit (N3/34) via the chassis CAN (CAN E):
Incoming signals via the chassis CAN (CAN E) from: | Incoming signals via the chassis CAN (CAN E) from: | Supplemental information |
Instrument cluster (IC) control unit (A1/1) | Instrument cluster (IC) control unit (A1/1) | - |
Supplemental restraint system control unit (SRS) (N2/18), | Supplemental restraint system control unit (SRS) (N2/18), | - |
Signal acquisition and actuation module (SAM) control unit (N10/1) | Signal acquisition and actuation module (SAM) control unit (N10/1) | Via interior CAN (CAN B) and electronic ignition lock control unit (EZS) (N73) |
Electronic Stability Program control unit (ESP) (N30/4) | Electronic Stability Program control unit (ESP) (N30/4) | Over electronic ignition lock (EIS) control unit (N73) |
Left front door control unit (N69/3) | Left front door control unit (N69/3) | Via interior CAN (CAN B) and electronic ignition lock control unit (EZS) (N73) |
Upper control panel control unit (UCP) (N72/1) | Upper control panel control unit (UCP) (N72/1) | Via battery sensor LIN (LIN B15), signal acquisition and actuation module (SAM) control unit (N10/1), interior CAN (CAN B) and electronic ignition lock control unit (EZS) (N73) |
Electronic ignition lock control unit (EIS) (N73) | Electronic ignition lock control unit (EIS) (N73) | - |
Automatic air conditioning control and operating unit (KLA-V&KLA-H) (S98) (with code HH4 (THERMOTRONIC automatic air conditioning)) and (with code HH9 (Semi-automatic regulated A/C, TEMPMATIC)) | Automatic air conditioning control and operating unit (KLA-V&KLA-H) (S98) (with code HH4 (THERMOTRONIC automatic air conditioning)) and (with code HH9 (Semi-automatic regulated A/C, TEMPMATIC)) | Via interior CAN (CAN B) and electronic ignition lock control unit (EZS) (N73) |
Diagnostic connector (X11) | Diagnostic connector (X11) | Via diagnostic CAN (CAN D) and electronic ignition lock control unit (EZS) (N73) |
Body
The housing of the ME-SFI [ME] control unit (N3/34) is made out of diecast aluminum and the cover is made out of corrosion-proof sheet steel. The ME-SFI [ME] control unit (N3/34) is water proof and dust proof.
The interior contains the measuring and control electronics for the engine management.
Power supply
The ME-SFI [ME] control unit (N3/34) is supplied with a voltage from "circuit 30 secured" and also for ignition ON from "circuit 87 ".
In the operating voltage range it has both short-circuit protection and reversed polarity protection.
Power is supplied through several engaged parallel pins connected in parallel to relieve the electrical connections.
Ground connection
The ground connection "circuit 31" is made over a number of ground lines to the front left ground point for lamp unit (W9).
No-load current shutoff
Information for partial function "no-load current shutoff" is documented in the function description "Engine OFF energy management function".
Variants
The variants of the engine management, for example country and exhaust variants, are activated with XENTRY Diagnostics over the variant coding.
Exchange of the ME-SFI [ME] control unit (N3/34) is not necessary.