In the world of automotive diagnostics, ECU remapping, and engine swapping, few control units are as ubiquitous in the late-model PSA Group (Peugeot and Citroën) vehicles as the Bosch ME7.4.5. This electronic control unit (ECU) manages some of the most popular engines of the early 2000s, including the TU5 and EW10 series. However, for mechanics and tuners, accessing the is often the critical step that stands between a dead engine and a running one.
| Pin | Signal | Description | Voltage/Note | |-----|--------|-------------|---------------| | T121/62 | B+ | Main battery supply (ECU relay) | 12V, always via main relay | | T121/87 | B+ | Second main supply | 12V | | T121/59 | B+ | Standby power for memory | 12V constant | | T121/1 | Ground | Power ground | Chassis ground | | T121/2 | Ground | Power ground | Chassis ground | | T121/3 | Ground | Sensor ground (analog) | Isolated from power ground | | T121/4 | Ground | Sensor ground (digital) | 0V reference | me7.4.5 pinout
This guide breaks down the essential connections for bench work and boot mode. Essential Bench Pinout (Plug C) In the world of automotive diagnostics, ECU remapping,