Bosch Motronic Ecu Pinout

| Resource | Best For | |----------|-----------| | BMW ETM (Electrical Troubleshooting Manual) | BMW-specific M1.3, M3.1, M3.3, M5.2 | | VAG Self-Study Program (SSP) | Audi/VW M1.5, M3.8, M5.2 | | Alfa Romeo Workshop Manuals | Motronic ML4.1 (Alfa 164/155) | | Volvo Greenbooks | Motronic 1.8 (Volvo 940/960) | | Porsche PET (Parts & Technical) | Motronic 2.10 (964/993) | | Tech websites: | | | - E30Zone Wiki (BMW M1.3 pinout) | | | - NefMoto (Motronic tuning & pinouts) | | | - Bosch Motronic ECU pinout database (Piggyback.com) | |

The main view is a schematic representation of the ECU plug.

If you only need to read codes or log data on a 55-pin Motronic, connect to pin 38 (K‑Line) with a VAG‑KKL cable or an OBD‑1 scanner. Power on pins 9 (+12V constant) and 10 (+12V switched). Ground pins 7, 8, and 41. bosch motronic ecu pinout

Let me know your ECU number or car make/model/year/engine code and I can give you the exact pinout.

You cannot guess. Using the wrong pinout can fry an ECU or sensor. Follow these steps: | Resource | Best For | |----------|-----------| |

| Motronic version | Pins | Used in | |----------------|------|--------------------------------------| | M1.3 | 35 | Early BMW E30, E24, E28 (1980s) | | M1.5.4 | 55 | VW Golf III / IV, Audi 80 / A4 | | M3.7 | 55 | BMW E36 (M50, M52), E34 (M60) | | M4.1 | 55 | Fiat Punto, Bravo, Alfa 145/146 | | ME7.5 | 81 | VW/Audi 1.8T, 2.8L (1998–2004) | | MED9.1 | 121 | BMW N45/N46, VW FSI (2004+) |

Application: Late 1990s Audi A4/S4 (1.8T 058 block), Passat, early VW Golf 4. The main view is a schematic representation of the ECU plug

M5.2 uses a 81-pin connector (2 rows, 41+40). This system added drive-by-wire (ETC) on some variants and wideband oxygen sensor control (LSU 4.2).

Notable pinout features: