Bosch Me20 Pinout Verified Page

: Critical for OBDII/bench diagnostic tools like KESS or K-Tag. Technical Considerations Bosch ECU Pinout Connections Guide | PDF | Engines - Scribd

Typically found on pins that require constant battery voltage (KL.30). Switched Power (Ignition): Connected to ignition-switched power (KL.15). Ground (GND): bosch me20 pinout verified

For those using the ME 2.0 in engine swap projects (such as the M104 or M112 engines), standalone startup requires ensuring that the Fuel Pump Relay trigger and Main Relay : Critical for OBDII/bench diagnostic tools like KESS

| Pin | Signal Name | Verified Function | Critical Note | | :--- | :--- | :--- | :--- | | | ECU Ground (Power) | High-current grounds for injectors | Must be < 0.1Ω to battery (-) | | 4, 5 | Battery Voltage (Permanent) | Direct 12V from fuse | Always powered | | 6 | Switched 12V (after relay) | 12V from main relay | Powers logic circuits | | 14 | CAN High (J1850/KWP2000) | Diagnostic bus (if used) | 2.5 – 3.5V | | 15 | CAN Low | Diagnostic bus | 1.5 – 2.5V | | 20 | O2 Sensor Heater (Pre-cat) | Ground control for heater | ~1.2A @ 12V | | 21 | O2 Sensor Heater (Post-cat) | Ground control for heater | As above | | 22 | Lambda 1 Signal (Pre-cat) | Narrowband O2 signal | 0.1 – 0.9V oscillating | | 23 | Lambda 2 Signal (Post-cat) | Narrowband O2 signal | 0.45V steady (if cat working) | | 30 | K-Line (ISO 9141) | Diagnostic communication | 0 – 12V pulsed | | 31, 32 | Shield grounds | For sensor cables | Continuity to pin 2 (black) | Ground (GND): For those using the ME 2