The Bosch is a widely used Engine Control Unit (ECU) found predominantly in late-model PSA Group vehicles (Peugeot and Citroën) and some models from Fiat and Lancia. It is an evolution of the earlier ME7.4 system, utilizing a faster processor and managing Euro 4 emission standards.
When swapping a failed ME7.4.5 ECU for a used unit from a salvage yard, the car will not start due to the integrated immobilizer rolling codes matching the original BSI (body control module) and keys. You have three pathways to resolve this: 1. Full Clone (Recommended)
Ensure you look at the pin layout from the perspective of the ECU pins, not the harness plug pins, as these are mirrored images of one another.
The processor is now sitting in boot mode. Open your software (e.g., Galletto or PyOBD using ST10F Flasher) select the correct ST10F275 profile, and click "Connect" or "Read". Cloning and Immobilizer (Immo) Considerations me7.4.5 pinout
Transferring data from a water-damaged ECU to a donor unit.
For detailed wiring diagrams related to specific engine components (like the accelerator pedal or cruise control), dedicated automotive forums like AutoDevice provide community-sourced mapping for retrofitting parts. or just the bench flashing Bosch ME7.4.5 ECU Pinout Guide | PDF | Computers - Scribd
When performing bench programming (reading/writing flash or eeprom), you will need to connect your tool (e.g., KESSV2, KTAG, Piasini) to specific pins. The Bosch is a widely used Engine Control
If attempting a boot read, ensure the resistor makes clean contact with the PCB pad without touching adjacent components.
To power up the ECU and establish a diagnostic link, connect your interface to the following specific pins: Power and Ground Connections Black Connector -> Pin H2 Switched +12V (Ignition Power): Black Connector -> Pin A4
: Automatically adjusts idle speed when it detects high-pressure loads from the power steering pump during full-lock turns. I can help more effectively if you tell me: Are you trying to do an IMMO OFF (immobiliser bypass)? Are you performing a bench flash or a remap ? You have three pathways to resolve this: 1
| Pin No. | Function | Description / Signal | | :--- | :--- | :--- | | | Battery Constant (+12V) | Permanent Battery Voltage (Unswitched) | | B02 | Ground (ECU) | Main ECU Ground (Connect to Chassis/Block) | | B03 | Ground (ECU) | Main ECU Ground | | B07 | Injectors Common | Common 12V supply feed for Injectors | | B08 | Injector Cylinder 1 | Ground trigger for Injector 1 | | B09 | Injector Cylinder 2 | Ground trigger for Injector 2 | | B10 | Injector Cylinder 3 | Ground trigger for Injector 3 | | B11 | Injector Cylinder 4 | Ground trigger for Injector 4 | | B16 | Tacho Output | RPM signal to dashboard cluster | | B21 | A/C Request | Air Conditioning request signal | | B22 | A/C Compressor Relay | Relay control for A/C Compressor | | B25 | Fuel Pump Relay | Relay control for Fuel Pump | | B28 | Fan Control Low | Cooling fan low speed relay | | B29 | Fan Control High | Cooling fan high speed relay | | B34 | Main Relay Control | Ground trigger for the Main Power Relay | | B39 | Charcoal Canister Valve | EVAP purge valve control |
This handbook summarizes the ME7.4.5 engine control unit (ECU) pinout, typical signal roles, wiring notes, diagnostic tips, and safe-handling procedures. It’s written for experienced technicians and advanced hobbyists working on vehicles that use Bosch ME7.4.5 ECUs (commonly found in many late-1990s to 2000s gasoline-powered European cars). Treat this as a reference supplement to factory service manuals — verify vehicle-specific diagrams before wiring or testing.