Bosch Motronic Ecu Pinout

The Bosch Motronic ECU pinout typically consists of several connectors, each with multiple pins that are assigned specific functions. The most common connectors include:

Comprehensive electrical tests and pin assignments are available at RTSAuto .

If you are working on a specific vehicle project, let me know the , car model , and production year . I can then provide more targeted diagnostic steps or specify the exact connector configuration for your project. Share public link

This specific ECU uses a 55-pin connector. For example: Pin 01: Output stage for ignition coil. Pin 03: Fuel pump relay control. Pin 07: Air mass sensor value (input). bosch motronic ecu pinout

Understanding which Motronic system you have is the first step in finding the correct pinout diagram.

The ECU outputs a ground signal to trigger the main EFI relay, which then feeds heavy-current power back into the ECU and engine actuators.

: A modern drive-by-wire system where the ECU controls throttle valve motors and electronic boost control. Typical Pin Functions The Bosch Motronic ECU pinout typically consists of

Pulse Width Modulation (PWM) drivers controlling idle stabilization valves or electronic throttle motors. Voltage References

| Pin # | Signal Name | Description | | --- | --- | --- | | 1 | Battery Voltage | Battery voltage supply | | 2 | Ground | Ground connection | | 3 | Crankshaft Position Sensor | Crankshaft position sensor signal | | 4 | Camshaft Position Sensor | Camshaft position sensor signal | | 5 | Throttle Position Sensor | Throttle position sensor signal | | 6 | Coolant Temperature Sensor | Coolant temperature sensor signal | | 7 | Intake Air Temperature Sensor | Intake air temperature sensor signal | | 8 | Oxygen Sensor | Oxygen sensor signal (lambda probe) | | 9 | Fuel Pump Relay | Fuel pump relay control | | 10 | Injector 1 | Injector 1 control | | 11 | Injector 2 | Injector 2 control | | 12 | Injector 3 | Injector 3 control | | 13 | Injector 4 | Injector 4 control | | 14 | Idle Air Control Valve | Idle air control valve control | | 15 | Fuel Injector Pulse | Fuel injector pulse width modulation | | 16 | Spark Plug 1 | Spark plug 1 control | | 17 | Spark Plug 2 | Spark plug 2 control | | 18 | Spark Plug 3 | Spark plug 3 control | | 19 | Spark Plug 4 | Spark plug 4 control | | 20 | Vehicle Speed Sensor | Vehicle speed sensor signal | | 21 | Brake Light Switch | Brake light switch signal | | 22 | Clutch Pedal Switch | Clutch pedal switch signal | | 23 | Gear Selector | Gear selector signal (automatic transmission) | | 24 | A/C Compressor | A/C compressor control | | 25 | Fan Control | Cooling fan control | | 26 | Heated Oxygen Sensor | Heated oxygen sensor control | | 27 | Fuel Level Sensor | Fuel level sensor signal | | 28 | Intake Manifold Pressure Sensor | Intake manifold pressure sensor signal | | 29 | EGR Valve | EGR valve control | | 30 | Canister Purge Valve | Canister purge valve control | | 31 | Idle Mixture Adjustment | Idle mixture adjustment | | 32 | CO Potentiometer | CO potentiometer signal | | 33 | Lambda Correction | Lambda correction signal | | 34 | Diagnostic Connector | Diagnostic connector (K-line) | | 35 | Ground | Ground connection | | 36 | Knock Sensor 1 | Knock sensor 1 signal | | 37 | Knock Sensor 2 | Knock sensor 2 signal | | 38 | Cylinder Head Temperature Sensor | Cylinder head temperature sensor signal | | 39 | Fuel Rail Pressure Sensor | Fuel rail pressure sensor signal | | 40 | Accelerator Pedal Position Sensor | Accelerator pedal position sensor signal | | 41 | Brake Pedal Position Sensor | Brake pedal position sensor signal | | 42 | Clutch Pedal Position Sensor | Clutch pedal position sensor signal | | 43 | Gearbox Computer | Gearbox computer communication | | 44 | Vehicle Check Connector | Vehicle check connector (optional) | | 45 | Service Connector | Service connector (optional) | | 46 | CAN Bus High | CAN bus high signal | | 47 | CAN Bus Low | CAN bus low signal | | 48 | Ground | Ground connection |

Bosch has used several distinct connector styles over the decades. Knowing which your ECU has helps in sourcing the correct diagram: I can then provide more targeted diagnostic steps

This guide provides a detailed breakdown of Bosch Motronic ECU pinouts across major generations, wiring identification strategies, and practical diagnostic procedures. 1. Evolution of Bosch Motronic Architecture

To provide mechanics and tuners with an interactive, model-specific wiring guide for Bosch Motronic ECUs, reducing the risk of wiring damage during diagnostics or tuning.