Bosch M7 Ecu Pinout |top| Official

Probe B5 (ECT signal) to B15 (ground) . With engine cold, voltage should be ~2.5V (20°C). Start engine – voltage should drop as coolant warms.

| Pin(s) | Function | Spec / Notes | |--------|-------------------------------|----------------------------------| | 37 | Battery voltage (permanent) | 12V, 10A fuse (ECU main) | | 3, 62 | Main relay output control | Switched 12V after relay | | 1, 2 | ECU ground (power) | Heavy gauge to engine block | | 4, 5 | Sensor ground (analog) | Common return for sensors | | 61 | Ignition switch input (Term.15)| 12V when key ON | Bosch M7 Ecu Pinout

[----------------- 121-PIN BOSCH M7 ECU -----------------] [ Pins 1 - 40 (Small Plug) ][ Pins 41 - 121 (Large Plug) ] Probe B5 (ECT signal) to B15 (ground)

If the K-Line or CAN lines are shorted by a failing ABS module or aftermarket radio wiring, diagnostics will fail. Unplug external modules one by one to see if ECU communication returns. | Pin(s) | Function | Spec / Notes

One of the most common configurations in this family is the 81-contact black connector found in Lada and other European vehicles. Below are critical pin assignments for this module: Pin 12 & 13 : Ground (Mass).

Pins 12 and 13 provide +12V power from the battery and ignition switch. Ground: Pin 51 and 53 are common ground points.

In this post, I’ll break down the standard 81-pin (or 55+ pin) Bosch M7 connector layout, explain the critical pins you need to start the engine, and show you how to identify the correct wiring for your specific vehicle.