BMW Bosch Motronic M1.7 ECU Pinout and Wiring Diagram. An indispensable reference for working with classic 4- and 6-cylinder BMW engines, such as the M42, M50, and M70 (V12). The M1.7 was one of the first fully digital ECUs. This guide includes:
- A complete pinout diagram for the unit's single connector.
- Detailed contact tables for all input and output signals (crankshaft sensor, air flow meter, and lambda sensor).
- Wiring diagrams for injectors, ignition coils, and sensors.
- Engine wiring diagrams for troubleshooting intermittent faults.
- Instructions for testing circuits and modules.
Ideal for diagnosing power supply, wiring, and engine swap issues on classic BMW E30, E34, and E36 models.
BMW E31 (1995-1996) M1.7 Pinout Schematic Diagram
BMW 8 Series E31 (840Ci, 850Ci, 850CSi) 1995-1996
BMW E31 (1993) M1.7 Pinout Schematic Diagram
BMW 8 Series E31 (850i) 1993
M70 Engine
M70 Engine
BMW E31 (1992) M1.7 Pinout Schematic Diagram
BMW 8 Series E31 (850i) 1992
M70 Engine
M70 Engine
BMW E31 (1991) M1.7 Pinout Schematic Diagram
BMW 8 Series E31 (850i) 1991
M70 Engine
M70 Engine
BMW E36 (1996) M1.7 Pinout Schematic Diagram
BMW E36 1996 318is/C, 325i/C, 328i/C, M3
Engine Control System DME M1.7 12-Cylinder M70 95-96
-
E = Input
-
A = Output
-
M = Ground
Pin Assignments
X6010
| Pin | Type | Description/Function | Connection |
| 1 | A | Fuel pump relay and crankshaft reference signal (TR) | Fuel pump relay |
| 2 | Not used | ||
| 3 | A | Fuel injector valves cyl. 2 - 4 - 6 | Fuel injector valves |
| 4 | Not used | ||
| 5 | Not used | ||
| 6 | M | Ground, fuel injector valve output stages | Ground point |
| 7 | Not used | ||
| 8 | A | Check engine | Instrument cluster |
| 9 | Not used | ||
| 10 | Not used | ||
| 11 | Not used | ||
| 12 | E | Wide open throttle signal (VL) | Electronic throttle control module (EML) |
| 13 | A | Free combustion | Mass air flow sensor |
| 14 | M | Ground, mass air flow sensor | Mass air flow sensor |
| 15 | Not used | ||
| 16 | E | Cylinder identification sensor (ignition) | Cylinder identification sensor (connection B) |
| 17 | A | Injection measuring signal (ti) (KVA signal) | Body electronics module (EKM) |
| 18 | Not used | ||
| 19 | Not used | ||
| 20 | Not used | ||
| 21 | Not used | ||
| 22 | Not used | ||
| 23 | Not used | ||
| 24 | Not used | ||
| 25 | A | Ignition, terminal 1 | Cyl. 1 - 6 ignition coil |
| 26 | E | Battery voltage | B+ junction point |
| 27 | A | Engine control module relay | Engine control module relay, terminal 85 |
| 28 | M | Ground for electronics and shielding the sensors | Ground point |
| 29 | Not used |
| Pin | Type | Description/Function | Connection |
| 30 | Not used | ||
| 31 | Not used | ||
| 32 | A | Fuel injector valves cyl. 1 - 3 - 5 | Fuel injector valves and electronic throttle control module (EML) |
| 33 | Not used | ||
| 34 | M | Ground, remaining output stages (except for ignition and fuel injector valves) | Ground point |
| 35 | Not used | ||
| 36 | A | Evaporative emission valve | Evaporative emission valve |
| 37 | Not used | ||
| 38 | Not used | ||
| 39 | Not used | ||
| 40 | Not used | ||
| 41 | E | Mass air flow sensor signal | Mass air flow sensor |
| 42 | Not used | ||
| 43 | M | Ground for sensors | Temperature sensors |
| 44 | E | Cylinder identification sensor (ignition) | Cylinder identification sensor (connection A) |
| 45 | Not used | ||
| 46 | Not used | ||
| 47 | Not used | ||
| 48 | A | Compressor cut-off signal | Compressor cut-off relay |
| 49 | Not used | ||
| 50 | Not used | ||
| 51 | Not used | ||
| 52 | Not used | ||
| 53 | Not used | ||
| 54 | E | Battery voltage | Engine control module relay |
| 55 | M | Ground, ignition | Ground point |
| 56 | E | Ignition, terminal 15 | Ignition switch |
| 57 | Not used | ||
| 58 | Not used | ||
| 59 | Not used | ||
| 60 | E | Programming voltage | Data link connector |
| Pin | Type | Description/Function | Connection |
| 61 | Not used | ||
| 62 | E | Idle signal (LL) | Electronic throttle control module (EML) |
| 63 | E | Torque converter clutch (WK) | Not used |
| 64 | E | Ignition timing intervention | Not used |
| 65 | E | Park/Neutral sensing | Not used |
| 66 | Not used | ||
| 67 | E | Inductive pulse generator (connection B) | Pulse generator, crankshaft rpm sensor |
| 68 | E | Inductive pulse generator (connection A) | Pulse generator, crankshaft rpm sensor |
| 69 | Not used | ||
| 70 | E | Oxygen sensor signal | Heated oxygen sensor |
| 71 | M | Ground, oxygen sensor | Heated oxygen sensor |
| 72 | Not used | ||
| 73 | E | Speedometer signal | Body electronics module (EKM) |
| 74 | A | Engine speed signal (TD) | Body electronics module (EKM) |
| 75 | Not used | ||
| 76 | E | Idle CO-potentiometer | Mass air flow sensor |
| 77 | E | Intake air temperature | Engine intake air temperature sensor |
| 78 | E | Engine coolant temperature | Engine coolant temperature sensor |
| 79 | Not used | ||
| 80 | Not used | ||
| 81 | E | Antitheft signal | Starter immobilization relay (early production) / Electronic immobilizer control module (EWS II) |
| 82 | E/A | Data link | Cyl. 7-12 engine control module (DME) |
| 83 | Not used | ||
| 84 | Not used | ||
| 85 | Not used | ||
| 86 | Not used | ||
| 87 | E | RxD diagnostic data line | Data link connector |
| 88 | E/A | TxD diagnostic data line | Data link connector |
TABLE OF FAULT CODES FOR DME 1.7
| Code | Fault Branch |
|---|---|
| x111 | Ignition |
| x211 | Control unit (self test) |
| x215 | Air mass sensor |
| x221 | Oxygen sensor |
| x222 | Oxygen control |
| x223 | NTC coolant (see fault example) |
| x224 | NTC intake air |
| x231 | Monitor of bat. voltage supply to contr. unit |
| x251 | Injector final stage 1 (cylinders 2,4,6) |
| x252 | Injector final stage (cylinders 1,3,5) |
| x261 | Elec. fuel pump relay final stage |
| x263 | Tank venting final stage |
| x264 | Relay 3 final stage (oxygen sensor heating) |
| x268 | Idle speed, CO potentiometer |
| x278 | Ignition timing correction |
| x512 | AC compressor shutoff |
| x513 | Final stage pin 18 |
| x515 | Converter lockup clutch |
| x516 | Speed signal |
| x517 | MSR signal |
| x518 | ASC signal |
| x818 | Final stage |
BMW DME Bosch Motronic M1.7 / M1.7.2 / M1.7.3 Catalog
| BMW Model / Chassis | Engine Code | Production Years / Period | DME Part Number (Bosch) | DME Version |
| 318is E30 | M42/B18 | 90 to 91 | 0 261 200 175 | Bosch Motronic M1.7 |
| 318i/is E36 | M42disa/B18 | 92 to 12/93 | 0 261 200 990 | Bosch Motronic M1.7 |
| 318i/is E36 | M42disall/B18 | 1/94 to 12/94 | 0 261 203 282 | Bosch Motronic M1.7.2 |
| 318i/is/Ti E36 | M42/B18 DISA2 | 1/95 to ... | 0 261 203 282 | Bosch Motronic M1.7.2 w/ EWS-II |
| 318i/is/Ti E36 | M42/B18 DISA2 | 1/95 to ... | 0 261 203 357 | Bosch Motronic M1.7.2 w/ EWS-II |
| Z3 E36 | 1.8L 8V (M44/B18) | 96 | — | Bosch Motronic M1.7.3 |
| 750iL E32 | M70/B50 | 91 | 0 261 200 352 | Bosch Motronic M1.7 |
| 850i E31 | M70/B50 | 91 | 0 261 200 352 | Bosch Motronic M1.7 |