Pin 15 is the crankshaft sensor input, and Pin 39 is the coolant temperature sensor input. Communication: Pin 71 serves as the K-Line for diagnostics. Bosch M7.2 (Common in BMW/B-Class Applications)
Note: Exact pin count and numbering depend on the ECU housing and vehicle harness. The following maps are representative typical assignments used in many M7 installations (Bosch M7.9.x / M7.4.x variants). Use them as a starting reference only.
The (e.g., 2002 Audi A4 1.8T).
Ultimate Guide to the Bosch M7 ECU Pinout: Wiring, Functions, and Bench Flashing
Peugeot 106/206/306, Citroën Saxo/Xsara/Xsara Picasso, Renault, early Chinese vehicles Bosch M7 Ecu Pinout
Power & ground
Connect and Pin 2 to the Power Supply Negative Terminal (-12V).
Pins 84 and 92 monitor feedback voltages to ensure safe operation. Fuel and Ignition Control
This connector handles the high-current drivers and critical engine synchronization. Pin 15 is the crankshaft sensor input, and
Manages fuel injectors, ignition coils, idle control valve, and emission controls.
Technicians frequently report failure patterns consistent with GND circuit damage on the PCB caused by coolant temperature sensor shorts.
| Pin № | Signal / Function | Notes / Wire Description | | :--- | :--- | :--- | | ||| | 12 | Terminal 30: Battery (+) | Permanent +12V power supply from battery | | 13 | Terminal 15: Ignition Switch (+) | Switched +12V from ignition switch | | 44 | Main Relay Power Input | +12V power input after the main relay | | 63 | Main Relay Power Input | +12V power input after the main relay | | 51 | ECU Ground | Main ground (power ground) | | 53 | ECU Ground | Main ground (power ground) | | 61 | Output Cascades Ground | Ground for output stages (injectors, coils) | | 5 (for 8v) / 6 (for 16v) | Ignition Coil Weight | Ground for ignition module | | Fuel Injection & Ignition ||| | 27 | Injector, Cylinder 1 (pulse) | Fuel injector control | | 6 | Injector, Cylinder 2 (pulse) | Fuel injector control | | 7 | Injector, Cylinder 3 (pulse) | Fuel injector control | | 47 | Injector, Cylinder 4 (pulse) | Fuel injector control | | 1 (8v) / 6 (16v) | Ignition coil, Cyl 1 (8v) / Cyl 1-4 (16v) | Ignition module output | | 2 (8v) / 4 (16v) | Ignition coil, Cyl 2 (8v) / Cyl 4 (16v) | Ignition module output | | 3 (8v) / 2 (16v) | Ignition coil, Cyl 3 (8v) / Cyl 2-3 (16v) | Ignition module output | | 4 (8v) / 3 (16v) | Ignition coil, Cyl 4 (8v) / Cyl 3 (16v) | Ignition module output | | Sensors ||| | 15 | Crankshaft sensor input (A) | Main timing signal from CKP sensor | | 34 | Crankshaft sensor input (B) | Additional CKP sensor signal | | 45 | Camshaft sensor power output | +5V or +12V supply for CMP sensor | | 64 | CKP sensor input (D) (on 16v) | Additional CKP signal for 16v engines (pin details) | | 16 | Throttle position sensor (TPS) input (C) | Signal from TPS | | 17 | TPS ground (B) | Sensor ground reference for TPS and Rough Road sensor | | 18 | Oxygen sensor 1 signal input (A) | Pre-cat lambda sensor signal | | 55 | Second oxygen sensor signal input (16v, Euro 3) | Post-cat lambda sensor signal for Euro 3 | | 19 | Knock sensor (KS) input | Knock sensor signal from engine block | | 20 | Knock sensor ground | Sensor ground reference for KS | | 37 | Mass Air Flow (MAF) sensor signal input | Airflow signal from MAF sensor | | 33 | MAF sensor power supply (+5V) | +5V reference voltage for MAF | | 36 | MAF sensor ground | Ground reference for MAF | | 39 | Coolant temperature sensor (CTS) signal input | Engine coolant temperature signal | | 40 | Intake air temperature sensor (IAT) signal input | Intake air temperature signal | | 35 | CTS & MAF & O₂ sensors ground | Shared ground for multiple sensors | | 59 | Vehicle speed sensor (VSS) signal | Speed signal for ECU (from speedometer) | | Actuators & Control ||| | 8 | Tachometer output | Signal for instrument cluster tachometer | | 14 | Main relay control output | Controls main engine management relay | | 28 | Second oxygen sensor heater control (16v) | Heater control for post-cat lambda | | 29 | Engine cooling fan control output (16v) | Relay control for radiator fan | | 31 | Check lamp (MIL) control | Malfunction Indicator Lamp (check engine) | | 46 | Canister purge valve control | Evaporative emissions solenoid control | | 48 | Oxygen sensor heater control (first) | Heater control for pre-cat lambda sensor | | 50 | Additional starter relay control | Engages starter relay (if equipped) | | Reference & Communications ||| | 10 | Fuel consumption signal | Signal for fuel consumption display | | 32 | TPS power supply (+5V) | +5V reference for TPS and Rough Road sensor | | 57 | Calibration data encoding input | Ground connection selects alternate fuel/ignition map stored in memory | | — | K-Line diagnostic | Typically on OBD-II pin 7 (not on main ECU connector in many installations) |
Inspect the ECU pins for physical damage, corrosion, or signs of water ingress (a common issue on cowl-mounted ECUs). Ultimate Guide to the Bosch M7 ECU Pinout:
Frequently used in Lada, Chery, and various Chinese-manufactured vehicles. It typically uses an 81-pin black connector. Core Pin Assignments (Bosch M7.9.7 Example)
Manages radiator fan activation based on CTS input. 3. Key Pin Identification Example (Bosch M7.9.7 Typical) Pin 1, 2, 3, 4: Fuel Injectors 1, 2, 3, 4 (Commonly) Pin 10: Ignition Control Pin 12: +12V Switched Power Pin 28: Ground (Sensor) Pin 63: TPS Signal Pin 64: MAP Sensor Signal Pin 70: Coolant Temperature Sensor Signal Pin 75: +12V Constant Power (Memory)
Technical training and wiring at Scribd - M7.4.4 Overview .