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HOWTO M111 on microRusEFI

See also Mercedes-OEM-ECU

See also Custom-M111-Full-Engine-Harness

See also OEM-harness-connectors#mercedes

  • Important suggestion: use Honda accelerator pedal position sensor (PPS) in the engine bay not Mercedes pedal position sensor
  • Honda OE part number: 37971-RBB-003, 37971-PZX-003, 37971-RCA-A01, 37971-RDA-A01
  • Replace Part Number: 5S8776, APS147, PPS1046, 72-7080, 1802-300281, 2-80046, SU10238, 699-199, 699199.

  • Connector: 6-way Pigtail for Honda Acura Throttle pedal sensor

  • Less important trick: 4 wire GM MAP+IAT

  • Less important trick: fuel pressure mod

Making my 190e More Fun (M111 SC Swap) - Forum

Case info - Forum

OEM C230 and SLK230 Wiring Diagrams

W202 C180 M111.921 with ME2.1

Getting started with the W202 ME2.1 ECU connector

This ECU has a CAR connector with 145 pins. Diagram with diagnostic pin assignment can be found here

How to read the following table:

Connector : Connector from A to F on the harness.

Pin: Pin number of the connector.

Name: this field was filled from the M111.921 wiring diagram.

Function: some human readable text.

ME2.1 Description: Based on me2.1 documenation what I have found for Alfa Rome.

MRE pin: Where to connect the pin (wiring example).

Comments: extra info that I learned during wiring in the ECU.

Connector Pin Number Name Function ME2.1 Description MRE pin Comments
A 1 NC NC NC NC
A 2 12V ACC Supply Supply MRE pin 1,5 12v Supply when ignition is on.
A 3 KL31(GND) Ground Ignition earth MRE pin 2,6 Supply earth
A 4 NC NC NC NC
A 5 O2 LSS O2 Heater Lambda sensor heater NC Only if you plan to use factory NB O2 sensor
A 6 FAN Control PWM to Fan control module Relay for 1st Fan Control MRE pin 33 (GP3) On some models this is PWM output and SAM ECU controls the FAN based on this. Note a 10hz/30% Duty is neaded to make the ecu happy, higher duty equals higher fan speed. 30% is off.
A 7 KL31(GND) Ignition Gnd Ignition earth MRE pin 2,6
A 8 KL31(GND) Sensors Gnd Electronic earth (for sensors) MRE pin 2,6
Connector Pin Number Name Function ME2.1 Description MRE pin Comments
B 1 NC NC NC
B 2 NC NC NC
B 3 Diag5 NC Programming NC
B 4 12V KL30 Permanent 12v supply Battery
Connector Pin Number Name Function ME2.1 Description MRE pin Comments
C 1 NC NC
C 2 NC NC
C 3 NC NC
C 4 NC NC
C 5 NC NC
C 6 NC NC
C 7 NC NC
C 8 NC NC
C 9 NC NC
C 10 NC NC
C 11 NC NC
C 12 NC NC
C 13 NC NC
C 14 NC NC
C 15 NC NC
C 16 NC NC
C 17 NC NC
C 18 NC NC
C 19 NC NC
C 20 NC NC
C 21 EVAP Solenoid Low side switch Fuel vapour recovery solenoid valve MRE pin 3 (LS2) Control this pin via FSIO.
C 22 Supply PPS1 5V supply for PPS Supply for potentiometer - 1 accelerator pedal MRE pin 44 (5V)
C 23 GND PPS1 Ground for PPS Earth for potentiometer - 1 accelerator pedal MRE pin 21 (GND)
C 24 Signal PPS1 Pedal Position1 Signal for potentiometer - 1 accelerator pedal MRE pin 31 (AV3)
C 25 Signal PPS2 Pedal Position2 Signal for potentiometer - 2 accelerator pedal MRE pin 30 (AV7)
C 26 GND PPS2 Ground for PPS Earth for potentiometer - 2 accelerator pedal MRE pin 21 (GND)
C 27 Supply PPS2 5V supply for PPS Supply for potentiometer - 2 accelerator pedal MRE pin 44 (5V)
C 28 NC Sport throttle response on warning light
C 29 Fuel Pump Low Side switch for FP relay Fuel pump relay MRE pin 35 (GP1)
C 30 NC NC
C 31 O2 Signal GND NB Heated O2 Signal GND Lambda sensor earth
C 32 O2 Signal NB Heated o2 Signal Lambda sensor signal
C 33 NC NC
C 34 NC NC
C 35 NC NC
C 36 NC NC
C 37 NC NC
C 38 DIAG Tacho out RPM Signal I send information over CAN.
C 39 DIAG K line Diagnostic connection (line K)
C 40 SAM? NC
Connector Pin Number Name Function ME2.1 Description MRE pin Comments
D 1 NC function MRE pin Comments
D 2 NC Relay for cooling fan 2 nd speed
D 3 Starter LSS Starter Relay NC MRE pin - I use just and external switch.
D 4 NC NC
D 5 NC CAE gear selector switch
D 6 NC NC
D 7 NC NC
D 8 NC NC
D 9 NC NC
D 10 NC NC
D 11 CAN_H Can High CAN line "high" MRE pin 48 (CANH)
D 12 CAN_L Can Low CAN line "low" MRE pin 47 (CANL)
D 13 NC Speedometer signal
D 14 NC Brake lights switch
D 15 NC NC
D 16 NC NC
D 17 NC CAE recognition
D 18 NC NC
D 19 NC Clutch Pedal
D 20 NC Cruise Control +
D 21 NC Cruise Control -
D 22 NC Cruie Control recall
D 23 NC Break Sw
D 24 NC Cruise Control deactivation
Connector Pin Number Name Function ME2.1 Description MRE pin Comments
E 1 NC Injector cyl. 3
E 2 NC Injector cyl. 6
E 3 NC NC
E 4 VVT LSS VVT coil LSS Air conditioning compressore relay feed MRE pin 7 (LS1) On My variant this is VVT, on other OEMs it is compressore clutch.
E 5 NC NC
E 6 NC NC
E 7 NC NC
E 8 NC NC
E 9 NC NC
E 10 NC Cruise control on warning light
E 11 NC NC
E 12 NC NC
E 13 Injector 4 Injector 4 Injector cyl. 2 MRE pin 42 (INJ4)
E 14 Injector 2 Injector 2 Injector cyl. 5 MRE pin 38 (INJ2)
E 15 NC Air conditioning pressure switch 1st stage
E 16 NC NC
E 17 Oil Switch Oil Level Switch Air conditioning pressure switch 2nd stage MRE pin In case this is used, it must be connected to a temperature input. This way we have a pull up inside MRE and this switch would drive the line low.
E 18 NC NC
E 19 NC NC
E 20 NC NC
E 21 NC Air conditioning request switch
E 22 NC NC
E 23 NC Sport throttle response switch
E 24 NC Sport throttle response switch earth
E 25 Injector 1 Injector 1 Injector cyl. 1 MRE pin 37 (INJ1)
E 26 Injector 3 Injector 3 Injector cyl. 4 MRE pin 41 (INJ3)
E 27 NC NC
E 28 CLT GND Signal GND Coolant temperature sensor earth MRE pin 21
E 29 CLT Signal CLT Signal Coolant temperature sensor signal MRE pin 18 (AT1)
E 30 NC NC
E 31 TPS1 TPS1 signal Potentiometer - 1 butterfly casing MRE pin 20 (AV5)
E 32 TPS GND TPS GND Earth for potentiometer 1-2 butterfly casing MRE pin 21
E 33 TPS Supply 5V TPS supply Supply for potentiometer 1-2 butterfly casing MRE pin 44 (5V)
E 34 TPS2 TPS2 signal Potentiometer - 2 butterfly casing MRE pin 25 (AV2)
E 35 NC NC
E 36 NC NC
E 37 CKP- VR- Rpm sensor (-) MRE pin 46 (VR-)
E 38 CKP+ VR+ Rpm sensor (+) MRE pin 45 (VR+)
E 39 CAM- CAM Sensor GND Timing sensor earths MRE pin 21 CAM supply in factory harness 12V
E 40 CAM+ CAM Signal Timing sensor signal MRE pin 25 (CAM)
E 41 KNOCK- Earth for detonation sensor 1 (cylinders 1-4-5) MRE pin
E 42 KNOCK+ Signal for detonation sensor 1 MRE pin Usable with diy external circuit.
E 43 NC Earth for detonation sensor 2 (cylinders 2-3-6)
E 44 NC Signal for detonation sensor 2
E 45 MAF Pin 1 IAT Signal Air temperature sensor MRE pin 23 (AT2)
E 46 MAF Pin 4 5V Supply Flow meter - reference voltage 5V MRE pin 39
E 47 MAF Pin 5 MAF Signal Output voltage (signal) - flow meter MRE pin 24 (AT3)
E 48 MAF Pin 3 Signal GND Earth - flow meter MRE pin 21

ToDo: add MRE pin assignment for IGN

Connector Pin Number Name Function ME2.1 Description MRE pin Comments
F 1 ETB- Butterfly casing motor integrated with D.V.L. (-) MRE pin 8 (ETB-)
F 2 ETB+ Butterfly casing motor integrated with D.V.L. (+) MRE pin 4 (ETB+)
F 3 NC NC
F 4 NC NC
F 5 NC Ignition coil for cyl. 6
F 6 NC Ignition coil for cyl. 2
F 7 NC NC
F 8 NC Earth
F 9 NC NC
F 10 NC NC
F 11 NC NC
F 12 NC NC
F 13 IGN1 Ignition coil for cyl. 4 OEM coils require external igniter!!
F 14 NC NC
F 15 KL31 (GND) NC
F 16 NC NC
F 17 NC Ignition coil for cyl. 3
F 18 NC NC
F 19 NC Ignition coil for cyl. 5
F 20 IGN2 Ignition coil for cyl. 1 OEM coils require external igniter!!
F 21 NC Operation of injection warning light