Bosch Me20 Pinout Verified ((new)) Jun 2026

Ultimate Guide to Bosch ME2.0 Pinout (Verified) The Bosch ME2.0 engine control unit (ECU) manages Mercedes-Benz M112 V6 and M113 V8 engines from the late 1990s and early 2000s. Mapping this ECU is essential for bench flashing, diagnostics, and troubleshooting.

Typically found on pins that require constant battery voltage (KL.30). Switched Power (Ignition): Connected to ignition-switched power (KL.15). Ground (GND):

When installing an engine equipped with an ME20 ECU into a different chassis, the original wiring harness is often modified or a standalone loom is built. Technicians need the pinout to wire the Check Engine Light (MIL), the Tachometer output, and the speedometer input directly into the dashboard of the recipient car. bosch me20 pinout verified

Plug D handles high-frequency output signals. If you are tracking down a misfire or a dead cylinder, check the continuity of these pins.

If your scan tool reads "Link Error" when connected to the ME20: Ultimate Guide to Bosch ME2

, the following basic power and communication pins are typically used: +12V Power : Often connected via

The ME20 relies on precise voltage signals to calculate fuel trims. Plug D handles high-frequency output signals

However, persistence paid off. After two weeks of waiting and with no response from India, a final attempt was made by reaching out to Bosch's Middle East team. This team proved to be the key, escalating the request to their engineering department. After a week, they provided the official pinout information. This shows that while the process can be challenging, going directly to a regional Bosch engineering hub is the most effective official method.

Before connecting any sensors or actuators, it's best to first test the power supply and ground pins (pins 42-48 for power and 43-46 for ground). Use a multimeter to check for the correct voltage and a solid ground connection.

The Bosch ME20 engine control unit (ECU) is a sophisticated piece of technology that manages engine functions in many vehicles, particularly from the late 1990s to early 2000s. However, finding a —a reliable, official pin assignment for the ECU’s connectors—is notoriously difficult.

| Pin | Function | Signal Type | Details / Notes | |-----|----------|-------------|------------------| | 1 | Ground (ECU) | GND | Main ground for ECU. | | 2 | Not used | – | – | | 3 | Ground (ECU) | GND | Additional ground. | | 4 | Not used | – | – | | 5 | +12V (battery) | Power | Permanent battery power. | | 6 | Not used | – | – | | 7 | Ground (ECU) | GND | Main ground. | | 8 | Not used | – | – | | 9 | +12V (ignition) | Power | Switched 12V from ignition relay. | | 10 | Not used | – | – | | 11 | Not used | – | – | | 12 | Not used | – | – | | 13 | Knock sensor 1 | Analog | Input from cylinder knock sensor (typically 0–5V). | | 14 | Knock sensor 2 | Analog | Input from knock sensor (for bank 2 on V‑engines). | | 15 | MAF sensor ground | GND | Reference ground for MAF sensor. | | 16 | MAF sensor signal | Analog | Mass airflow sensor signal (0–5V). | | 17 | Intake air temp | Analog | IAT sensor signal (0–5V). | | 18 | Coolant temp | Analog | Engine coolant temperature (ECT) sensor (0–5V). | | 19 | Not used | – | – | | 20 | Throttle position (TP1) | Analog | TP sensor 1 (closed throttle ~0.2–0.5V, WOT ~4.3–4.8V). | | 21 | Throttle position (TP2) | Analog | TP sensor 2 (closed throttle ~0.1–0.4V, WOT ~2.1–2.5V). | | 22 | Reference 5V out | Power | 5V reference voltage for TP sensors and other sensors. | | 23 | Accelerator pedal (APP1) | Analog | Pedal value sensor 1 (0–5V). | | 24 | Accelerator pedal (APP2) | Analog | Pedal value sensor 2 (0–5V). | | 25 | Reference 5V out | Power | 5V reference for pedal sensors. | | 26 | Not used | – | – | | 27 | Not used | – | – | | 28 | O2 sensor heater | PWM | Heater control for lambda sensor. | | 29 | Not used | – | – | | 30 | Not used | – | – | | 31 | CAN Low | Digital | CAN bus communication. | | 32 | CAN High | Digital | CAN bus communication. | | 33 | K‑Line | Digital | Diagnostic communication (ISO 9141). | | 34 | Ignition output 1 | Digital | Coil driver for cylinder 1 (and 4 if wasted spark). | | 35 | Ignition output 2 | Digital | Coil driver for cylinder 2 (and 5 if wasted spark). | | 36 | Ignition output 3 | Digital | Coil driver for cylinder 3 (and 6 if wasted spark). | | 37 | Ignition output 4 | Digital | Coil driver for cylinder 4 (if individual coils). | | 38 | Not used | – | – | | 39 | Not used | – | – | | 40 | Injector 1 | Digital | Fuel injector driver (ground‑side switched). | | 41 | Injector 2 | Digital | Fuel injector driver. | | 42 | Injector 3 | Digital | Fuel injector driver. | | 43 | Injector 4 | Digital | Fuel injector driver. | | 44 | Injector 5 | Digital | Fuel injector driver (if V6). | | 45 | Injector 6 | Digital | Fuel injector driver (if V6). | | 46 | Injector ground | GND | Power ground for injector drivers. | | 47 | Injector ground | GND | Power ground for injector drivers. | | 48 | EVAP purge valve | PWM | Evaporative emission purge valve control. | | 49 | Idle air control (IAC) | PWM | Idle air control valve (if not electronic throttle). | | 50 | A/C compressor relay | Digital | A/C compressor clutch control. | | 51 | Fuel pump relay | Digital | Fuel pump relay control. | | 52 | Main relay | Digital | Main relay (powers ECU and major components). | | 53 | MIL (check engine light) | Digital | Malfunction indicator lamp output. | | 54 | Not used | – | – | | 55 | Not used | – | – |