BMW 3 Series E36 1990–2000 (M50/M52) → DTAFast T12 (auto)
BMW 3 Series E36 1990–2000 (M50/M52) — DTAFast — T12
⚠ NOT CHECKED. Don't build from this.
Drawn by Michael Gnankou · Rev 0 · draft · 2026-10-09
Before you start
Not confident with automotive wiring? Have a professional harness builder or tuner do it, or check your work before first power-up. A wiring mistake can damage the ECU, the engine or the car, or start a fire.
| Status | draft · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | 1: read the Findings page before cutting any wire |
| Size of the job | 48 wires · 7 connectors · 1 part lines |
| Tools | Crimp and extraction tools for each terminal family (see Connectors) · wire strippers · multimeter · heat gun + heat-shrink |
| Order of work | 1. Check every part against the parts list. 2. Cut and label every wire (labels: Export → Wire labels). 3. Crimp and pin connector by connector, ticking the build checklist. 4. Run the bench test with nothing plugged in and the battery disconnected. 5. Only then connect the ECU and power up. |
Build checklist
Tick each box as you go. Continuity: meter from end to end, expect under 1 Ω.
| Wire | From | To | Gauge | Colour | Cut | Label | Crimp A | Crimp B | Pin A | Pin B | Continuity |
|---|---|---|---|---|---|---|---|---|---|---|---|
| W1 | OEM-X-54 | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | SP-14V-1 | T12-C1-31 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-X-26 | T12-C3-26 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | OEM-X-15 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | OEM-X-34 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-X-55 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-X-6 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | SP-GND-1 | T12-C1-13 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-GND-1 | T12-C1-14 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | OEM-X-28 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-X-40 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-X-43 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | OEM-X-44 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-X-71 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | SP-0V-1 | T12-C2-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | SP-0V-1 | T12-C2-33 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-X-59 | T12-C2-24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-X-16 | T12-C2-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-X-17 | T12-C2-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-X-70 | T12-C3-31 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-X-69 | T12-C3-32 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-X-50 | T12-C1-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-X-51 | T12-C1-18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-X-52 | T12-C1-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-X-23 | T12-C1-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-X-25 | T12-C1-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-X-24 | T12-C1-27 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-X-33 | T12-C1-9 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-X-32 | T12-C1-17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-X-31 | T12-C1-34 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-X-5 | T12-C1-25 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-X-3 | T12-C1-16 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-X-4 | T12-C1-15 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-X-1 | T12-C1-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-X-27 | T12-C1-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-X-38 | T12-C3-9 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-X-2 | T12-C1-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-X-29 | T12-C3-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-X-36 | T12-C3-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-X-7 | T12-C3-24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-X-8 | T12-C3-25 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W42 | OEM-X-47 | T12-C3-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W43 | OEM-X-41 | T12-C2-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W44 | OEM-X-73 | T12-C2-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W45 | OEM-X-13 | T12-C2-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W46 | OEM-X-78 | T12-C2-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W47 | OEM-X-77 | T12-C2-25 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W48 | OEM-X-42 | T12-C2-2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ |
Bench test (before first power-up)
Battery disconnected, ECU and every sensor unplugged. Meter on resistance. Each pair below must read open (OL): a reading means a pinched wire, a stray strand or a mis-pinned cavity. Then check continuity of every wire (last column of the build checklist).
| # | Probe A | Probe B | Expect | Why | Reading |
|---|---|---|---|---|---|
| 1 | T12-C3-26 | T12-C2-21 | open (OL) | +12 V supply must not touch sensor ground | |
| 2 | T12-C1-13 | T12-C1-31 | open (OL) | power ground must not touch +12 V supply | |
| 3 | T12-C1-13 | T12-C2-24 | open (OL) | power ground must not touch 5 V sensor reference | |
| 4 | T12-C1-13 | T12-C3-26 | open (OL) | power ground must not touch +12 V supply | |
| 5 | T12-C1-31 | T12-C2-24 | open (OL) | +12 V supply must not touch 5 V sensor reference | |
| 6 | T12-C2-21 | T12-C1-31 | open (OL) | sensor ground must not touch +12 V supply | |
| 7 | T12-C2-21 | T12-C2-24 | open (OL) | sensor ground must not touch 5 V sensor reference | |
| 8 | T12-C3-26 | T12-C2-24 | open (OL) | +12 V supply must not touch 5 V sensor reference |
If any reading doesn't match, stop and get help before powering up.
Revisions
| Rev | Label | By | Date |
|---|---|---|---|
| No revisions yet. | |||
Schematic
Connectors
OEM-X
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Fuel pump relay control | — | W34 | — | 0.5 | T12-C1-5 | — | — | — |
| 13 | O2 sensor signal | — | W45 | — | 0.5 | T12-C2-5 | — | — | — |
| 15 | Ground | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| 16 | Crank position sensor (+) | — | W18 | — | 0.5 | T12-C2-12 | — | — | — |
| 17 | Camshaft position sensor (Hall) | — | W19 | — | 0.5 | T12-C2-22 | — | — | — |
| 2 | Idle speed control valve (close winding) | — | W37 | — | 0.5 | T12-C1-3 | — | — | — |
| 23 | Ignition coil cylinder 4 | — | W25 | — | 0.5 | T12-C1-26 | — | — | — |
| 24 | Ignition coil cylinder 6 | — | W27 | — | 0.5 | T12-C1-27 | — | — | — |
| 25 | Ignition coil cylinder 5 | — | W26 | — | 0.5 | T12-C1-11 | — | — | — |
| 26 | Battery voltage (constant +12V) | — | W3 | — | 0.85 | T12-C3-26 | — | — | — |
| 27 | Main relay control | — | W35 | — | 0.5 | T12-C1-4 | — | — | — |
| 28 | Ground (electronics + sensor shielding) | — | W10 | — | 0.5 | SP-0V-1 | — | — | — |
| 29 | Idle speed control valve (open winding) | — | W38 | — | 0.5 | T12-C3-22 | — | — | — |
| 3 | Injector cylinder 5 | — | W32 | — | 0.5 | T12-C1-16 | — | — | — |
| 31 | Injector cylinder 3 | — | W30 | — | 0.5 | T12-C1-34 | — | — | — |
| 32 | Injector cylinder 2 | — | W29 | — | 0.5 | T12-C1-17 | — | — | — |
| 33 | Injector cylinder 1 | — | W28 | — | 0.5 | T12-C1-9 | — | — | — |
| 34 | Ground (output stages) | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| 36 | Evap purge solenoid | — | W39 | — | 0.5 | T12-C3-23 | — | — | — |
| 38 | O2 sensor heater relay control | — | W36 | — | 0.5 | T12-C3-9 | — | — | — |
| 4 | Injector cylinder 6 | — | W33 | — | 0.5 | T12-C1-15 | — | — | — |
| 40 | O2 sensor signal ground | — | W11 | — | 0.5 | SP-0V-1 | — | — | — |
| 41 | Mass air flow (MAF) signal | — | W43 | — | 0.5 | T12-C2-10 | — | — | — |
| 42 | Vehicle speed signal | — | W48 | — | 0.5 | T12-C2-2 | — | — | — |
| 43 | Crank position sensor (-) | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| 44 | Sensor ground (IAT/ECT/TPS) | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 45 | Shield ground | — | — | — | — | — | — | — | — |
| 47 | Tachometer output | — | W42 | — | 0.5 | T12-C3-10 | — | — | — |
| 5 | Injector cylinder 4 | — | W31 | — | 0.5 | T12-C1-25 | — | — | — |
| 50 | Ignition coil cylinder 1 | — | W22 | — | 0.5 | T12-C1-10 | — | — | — |
| 51 | Ignition coil cylinder 2 | — | W23 | — | 0.5 | T12-C1-18 | — | — | — |
| 52 | Ignition coil cylinder 3 | — | W24 | — | 0.5 | T12-C1-1 | — | — | — |
| 54 | ECU power (+14V from main relay) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| 55 | Ground (ignition) | — | W6 | — | 0.85 | SP-GND-1 | — | — | — |
| 56 | Ignition switch (terminal 15) | — | — | — | — | — | — | — | — |
| 59 | +5V sensor supply | — | W17 | — | 0.5 | T12-C2-24 | — | — | — |
| 6 | Ground (injector output stages) | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| 69 | Knock sensor cylinders 4-6 | — | W21 | — | 0.5 | T12-C3-32 | — | — | — |
| 7 | VANOS intake camshaft solenoid | — | W40 | — | 0.5 | T12-C3-24 | — | — | — |
| 70 | Knock sensor cylinders 1-3 | — | W20 | — | 0.5 | T12-C3-31 | — | — | — |
| 71 | Knock sensor ground/shield | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| 73 | Throttle position (TPS) | — | W44 | — | 0.5 | T12-C2-1 | — | — | — |
| 77 | Intake air temperature (IAT) | — | W47 | — | 0.5 | T12-C2-25 | — | — | — |
| 78 | Engine coolant temperature (ECT) | — | W46 | — | 0.5 | T12-C2-7 | — | — | — |
| 8 | Check engine light (MIL) | — | W41 | — | 0.5 | T12-C3-25 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W10 | — | 0.5 | OEM-X-28 | — | — | — |
| 1 | — | — | W11 | — | 0.5 | OEM-X-40 | — | — | — |
| 1 | — | — | W12 | — | 0.5 | OEM-X-43 | — | — | — |
| 1 | — | — | W13 | — | 0.5 | OEM-X-44 | — | — | — |
| 1 | — | — | W14 | — | 0.5 | OEM-X-71 | — | — | — |
| 1 | — | — | W15 | — | 0.5 | T12-C2-21 | — | — | — |
| 1 | — | — | W16 | — | 0.5 | T12-C2-33 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-X-54 | — | — | — |
| 1 | — | — | W2 | — | 0.85 | T12-C1-31 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W4 | — | 0.85 | OEM-X-15 | — | — | — |
| 1 | — | — | W5 | — | 0.85 | OEM-X-34 | — | — | — |
| 1 | — | — | W6 | — | 0.85 | OEM-X-55 | — | — | — |
| 1 | — | — | W7 | — | 0.85 | OEM-X-6 | — | — | — |
| 1 | — | — | W8 | — | 0.85 | T12-C1-13 | — | — | — |
| 1 | — | — | W9 | — | 0.85 | T12-C1-14 | — | — | — |
T12-C1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Coil 3 | — | W24 | — | 0.5 | OEM-X-52 | — | — | — |
| 10 | Coil 1 | — | W22 | — | 0.5 | OEM-X-50 | — | — | — |
| 11 | Coil 5 | — | W26 | — | 0.5 | OEM-X-25 | — | — | — |
| 12 | Coil 7 | — | — | — | — | — | — | — | — |
| 13 | Power Ground 1 | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| 14 | Power Ground 2 | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
| 15 | Injector 6 | — | W33 | — | 0.5 | OEM-X-4 | — | — | — |
| 16 | Injector 5 | — | W32 | — | 0.5 | OEM-X-3 | — | — | — |
| 17 | Injector 2 | — | W29 | — | 0.5 | OEM-X-32 | — | — | — |
| 18 | Coil 2 | — | W23 | — | 0.5 | OEM-X-51 | — | — | — |
| 19 | Coil 8 | — | — | — | — | — | — | — | — |
| 2 | Coil 11 | — | — | — | — | — | — | — | — |
| 20 | Coil 9 | — | — | — | — | — | — | — | — |
| 21 | Injector 9 | — | — | — | — | — | — | — | — |
| 22 | Injector 10 | — | — | — | — | — | — | — | — |
| 23 | Injector 8 | — | — | — | — | — | — | — | — |
| 24 | Injector 7 | — | — | — | — | — | — | — | — |
| 25 | Injector 4 | — | W31 | — | 0.5 | OEM-X-5 | — | — | — |
| 26 | Coil 4 | — | W25 | — | 0.5 | OEM-X-23 | — | — | — |
| 27 | Coil 6 | — | W27 | — | 0.5 | OEM-X-24 | — | — | — |
| 28 | Coil 10 | — | — | — | — | — | — | — | — |
| 29 | Motor 2 + | — | — | — | — | — | — | — | — |
| 3 | PWM 3 | — | W37 | — | 0.5 | OEM-X-2 | — | — | — |
| 30 | Motor 2 - | — | — | — | — | — | — | — | — |
| 31 | Ignition 12v In | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| 32 | Injector 12 | — | — | — | — | — | — | — | — |
| 33 | Coil 12 | — | — | — | — | — | — | — | — |
| 34 | Injector 3 | — | W30 | — | 0.5 | OEM-X-31 | — | — | — |
| 4 | PWM 2 | — | W35 | — | 0.5 | OEM-X-27 | — | — | — |
| 5 | PWM 1 | — | W34 | — | 0.5 | OEM-X-1 | — | — | — |
| 6 | Motor 1 + | — | — | — | — | — | — | — | — |
| 7 | Motor 1 - | — | — | — | — | — | — | — | — |
| 8 | Injector 11 | — | — | — | — | — | — | — | — |
| 9 | Injector 1 | — | W28 | — | 0.5 | OEM-X-33 | — | — | — |
T12-C2
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Analogue 2 | — | W44 | — | 0.5 | OEM-X-73 | — | — | — |
| 10 | Analogue 1 | — | W43 | — | 0.5 | OEM-X-41 | — | — | — |
| 11 | Digital 3 | — | — | — | — | — | — | — | — |
| 12 | Crank | — | W18 | — | 0.5 | OEM-X-16 | — | — | — |
| 13 | Analogue 12 | — | — | — | — | — | — | — | — |
| 14 | Digital 4 | — | — | — | — | — | — | — | — |
| 15 | Digital 5 | — | — | — | — | — | — | — | — |
| 16 | Analogue 11 | — | — | — | — | — | — | — | — |
| 17 | Thermistor 3 | — | — | — | — | — | — | — | — |
| 18 | Analogue 5 | — | — | — | — | — | — | — | — |
| 19 | Analogue 6 | — | — | — | — | — | — | — | — |
| 2 | Wheel 1 | — | W48 | — | 0.5 | OEM-X-42 | — | — | — |
| 20 | Wheel 2 | — | — | — | — | — | — | — | — |
| 21 | Sensor Ground | — | W15 | — | 0.5 | SP-0V-1 | — | — | — |
| 22 | Cam 1 | — | W19 | — | 0.5 | OEM-X-17 | — | — | — |
| 23 | Cam 3 | — | — | — | — | — | — | — | — |
| 24 | 5v Output | — | W17 | — | 0.5 | OEM-X-59 | — | — | — |
| 25 | Thermistor 2 | — | W47 | — | 0.5 | OEM-X-77 | — | — | — |
| 26 | CAN High | — | — | — | — | — | — | — | — |
| 27 | Digital 6 | — | — | — | — | — | — | — | — |
| 28 | CAN Low | — | — | — | — | — | — | — | — |
| 29 | Cam 2 | — | — | — | — | — | — | — | — |
| 3 | Analogue 10 | — | — | — | — | — | — | — | — |
| 30 | Cam 4 | — | — | — | — | — | — | — | — |
| 31 | Wheel 3 | — | — | — | — | — | — | — | — |
| 32 | Wheel 4 | — | — | — | — | — | — | — | — |
| 33 | Sensor Ground | — | W16 | — | 0.5 | SP-0V-1 | — | — | — |
| 34 | Analogue 9 | — | — | — | — | — | — | — | — |
| 4 | Digital 1 | — | — | — | — | — | — | — | — |
| 5 | Analogue 3 | — | W45 | — | 0.5 | OEM-X-13 | — | — | — |
| 6 | Analogue 4 | — | — | — | — | — | — | — | — |
| 7 | Thermistor 1 | — | W46 | — | 0.5 | OEM-X-78 | — | — | — |
| 8 | Digital 2 | — | — | — | — | — | — | — | — |
| 9 | 5v Output | — | — | — | — | — | — | — | — |
T12-C3
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Lambda 2 Pump Current | — | — | — | — | — | — | — | — |
| 10 | PWM 8 | — | W42 | — | 0.5 | OEM-X-47 | — | — | — |
| 11 | Lambda 1 Trim Resistor | — | — | — | — | — | — | — | — |
| 12 | Lambda 1 Nernst Voltage | — | — | — | — | — | — | — | — |
| 13 | Analogue 13 | — | — | — | — | — | — | — | — |
| 14 | Analogue 14 | — | — | — | — | — | — | — | — |
| 15 | Analogue 15 | — | — | — | — | — | — | — | — |
| 16 | Analogue 16 | — | — | — | — | — | — | — | — |
| 17 | Analogue 7 | — | — | — | — | — | — | — | — |
| 18 | Analogue 8 | — | — | — | — | — | — | — | — |
| 19 | Digital 7 | — | — | — | — | — | — | — | — |
| 2 | Lambda 2 VGND | — | — | — | — | — | — | — | — |
| 20 | Digital 8 | — | — | — | — | — | — | — | — |
| 21 | Digital 9 | — | — | — | — | — | — | — | — |
| 22 | PWM 4 | — | W38 | — | 0.5 | OEM-X-29 | — | — | — |
| 23 | PWM 5 | — | W39 | — | 0.5 | OEM-X-36 | — | — | — |
| 24 | PWM 6 | — | W40 | — | 0.5 | OEM-X-7 | — | — | — |
| 25 | PWM 7 | — | W41 | — | 0.5 | OEM-X-8 | — | — | — |
| 26 | Permanent 12v | — | W3 | — | 0.85 | OEM-X-26 | — | — | — |
| 27 | Permanent 12v | — | — | — | — | — | — | — | — |
| 28 | PWM 10 | — | — | — | — | — | — | — | — |
| 29 | PWM 11 | — | — | — | — | — | — | — | — |
| 3 | Lambda 2 Heater Negative | — | — | — | — | — | — | — | — |
| 30 | PWM 12 | — | — | — | — | — | — | — | — |
| 31 | Knock 1 | — | W20 | — | 0.5 | OEM-X-70 | — | — | — |
| 32 | Knock 2 | — | W21 | — | 0.5 | OEM-X-69 | — | — | — |
| 33 | CAN 2 High | — | — | — | — | — | — | — | — |
| 34 | CAN 2 Low | — | — | — | — | — | — | — | — |
| 4 | PWM 9 | — | — | — | — | — | — | — | — |
| 5 | Lambda 2 Trim Resistor | — | — | — | — | — | — | — | — |
| 6 | Lambda 2 Nernst Voltage | — | — | — | — | — | — | — | — |
| 7 | Lambda 1 Pump Current | — | — | — | — | — | — | — | — |
| 8 | Lambda 1 VGND | — | — | — | — | — | — | — | — |
| 9 | Lambda 1 Heater Negative | — | W36 | — | 0.5 | OEM-X-38 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-X-1 | Fuel pump relay control | low_side_out | T12-C1-5 | PWM 1 | low_side_out | corroborated | |
| OEM-X-13 | O2 sensor signal | lambda_nb_in | T12-C2-5 | Analogue 3 | analog_in | corroborated | |
| OEM-X-15 | Ground | ground | T12-C1-13 + T12-C1-14 | Power Ground 1 + Power Ground 2 | ground | corroborated | |
| OEM-X-16 | Crank position sensor (+) | trigger_in | T12-C2-12 | Crank | trigger_in | corroborated | |
| OEM-X-17 | Camshaft position sensor (Hall) | trigger_in | T12-C2-22 | Cam 1 | trigger_in | corroborated | |
| OEM-X-2 | Idle speed control valve (close winding) | low_side_out | T12-C1-3 | PWM 3 | low_side_out | corroborated | |
| OEM-X-23 | Ignition coil cylinder 4 | ignition_out | T12-C1-26 | Coil 4 | ignition_out | corroborated | |
| OEM-X-24 | Ignition coil cylinder 6 | ignition_out | T12-C1-27 | Coil 6 | ignition_out | corroborated | |
| OEM-X-25 | Ignition coil cylinder 5 | ignition_out | T12-C1-11 | Coil 5 | ignition_out | corroborated | |
| OEM-X-26 | Battery voltage (constant +12V) | power_in | T12-C3-26 | Permanent 12v | power_in | corroborated | |
| OEM-X-27 | Main relay control | low_side_out | T12-C1-4 | PWM 2 | low_side_out | corroborated | |
| OEM-X-28 | Ground (electronics + sensor shielding) | sensor_ground | T12-C2-21 + T12-C2-33 | Sensor Ground + Sensor Ground | sensor_ground | corroborated | |
| OEM-X-29 | Idle speed control valve (open winding) | low_side_out | T12-C3-22 | PWM 4 | low_side_out | corroborated | |
| OEM-X-3 | Injector cylinder 5 | injector_out | T12-C1-16 | Injector 5 | injector_out | corroborated | |
| OEM-X-31 | Injector cylinder 3 | injector_out | T12-C1-34 | Injector 3 | injector_out | corroborated | |
| OEM-X-32 | Injector cylinder 2 | injector_out | T12-C1-17 | Injector 2 | injector_out | corroborated | |
| OEM-X-33 | Injector cylinder 1 | injector_out | T12-C1-9 | Injector 1 | injector_out | corroborated | |
| OEM-X-34 | Ground (output stages) | ground | T12-C1-13 + T12-C1-14 | Power Ground 1 + Power Ground 2 | ground | corroborated | |
| OEM-X-36 | Evap purge solenoid | low_side_out | T12-C3-23 | PWM 5 | low_side_out | corroborated | |
| OEM-X-38 | O2 sensor heater relay control | low_side_out | T12-C3-9 | Lambda 1 Heater Negative | low_side_out | corroborated | |
| OEM-X-4 | Injector cylinder 6 | injector_out | T12-C1-15 | Injector 6 | injector_out | corroborated | |
| OEM-X-40 | O2 sensor signal ground | sensor_ground | T12-C2-21 + T12-C2-33 | Sensor Ground + Sensor Ground | sensor_ground | corroborated | |
| OEM-X-41 | Mass air flow (MAF) signal | analog_in | T12-C2-10 | Analogue 1 | analog_in | corroborated | |
| OEM-X-42 | Vehicle speed signal | digital_in | T12-C2-2 | Wheel 1 | digital_in | corroborated | |
| OEM-X-43 | Crank position sensor (-) | sensor_ground | T12-C2-21 + T12-C2-33 | Sensor Ground + Sensor Ground | sensor_ground | corroborated | |
| OEM-X-44 | Sensor ground (IAT/ECT/TPS) | sensor_ground | T12-C2-21 + T12-C2-33 | Sensor Ground + Sensor Ground | sensor_ground | corroborated | |
| OEM-X-45 | Shield ground | shield | — | — | — | corroborated | |
| OEM-X-47 | Tachometer output | tacho_out | T12-C3-10 | PWM 8 | low_side_out | corroborated | |
| OEM-X-5 | Injector cylinder 4 | injector_out | T12-C1-25 | Injector 4 | injector_out | corroborated | |
| OEM-X-50 | Ignition coil cylinder 1 | ignition_out | T12-C1-10 | Coil 1 | ignition_out | corroborated | |
| OEM-X-51 | Ignition coil cylinder 2 | ignition_out | T12-C1-18 | Coil 2 | ignition_out | corroborated | |
| OEM-X-52 | Ignition coil cylinder 3 | ignition_out | T12-C1-1 | Coil 3 | ignition_out | corroborated | |
| OEM-X-54 | ECU power (+14V from main relay) | power_in | T12-C1-31 | Ignition 12v In | power_in | corroborated | |
| OEM-X-55 | Ground (ignition) | ground | T12-C1-13 + T12-C1-14 | Power Ground 1 + Power Ground 2 | ground | corroborated | |
| OEM-X-56 | Ignition switch (terminal 15) | digital_in | — | — | — | corroborated | |
| OEM-X-59 | +5V sensor supply | vref | T12-C2-24 | 5v Output | vref | corroborated | |
| OEM-X-6 | Ground (injector output stages) | ground | T12-C1-13 + T12-C1-14 | Power Ground 1 + Power Ground 2 | ground | corroborated | |
| OEM-X-69 | Knock sensor cylinders 4-6 | knock_in | T12-C3-32 | Knock 2 | knock_in | corroborated | |
| OEM-X-7 | VANOS intake camshaft solenoid | low_side_out | T12-C3-24 | PWM 6 | low_side_out | corroborated | |
| OEM-X-70 | Knock sensor cylinders 1-3 | knock_in | T12-C3-31 | Knock 1 | knock_in | corroborated | |
| OEM-X-71 | Knock sensor ground/shield | sensor_ground | T12-C2-21 + T12-C2-33 | Sensor Ground + Sensor Ground | sensor_ground | corroborated | |
| OEM-X-73 | Throttle position (TPS) | analog_in | T12-C2-1 | Analogue 2 | analog_in | corroborated | |
| OEM-X-77 | Intake air temperature (IAT) | temp_in | T12-C2-25 | Thermistor 2 | temp_in | corroborated | |
| OEM-X-78 | Engine coolant temperature (ECT) | temp_in | T12-C2-7 | Thermistor 1 | temp_in | corroborated | |
| OEM-X-8 | Check engine light (MIL) | low_side_out | T12-C3-25 | PWM 7 | low_side_out | corroborated |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-X-54 | SP-14V-1 | 0.85 | no route | ECU power (+14V from main relay) | — | |
| W2 | SP-14V-1 | T12-C1-31 | 0.85 | no route | Ignition 12v In | — | |
| W3 | OEM-X-26 | T12-C3-26 | 0.85 | no route | Battery voltage (constant +12V) | — | |
| W4 | OEM-X-15 | SP-GND-1 | 0.85 | no route | Ground | — | |
| W5 | OEM-X-34 | SP-GND-1 | 0.85 | no route | Ground (output stages) | — | |
| W6 | OEM-X-55 | SP-GND-1 | 0.85 | no route | Ground (ignition) | — | |
| W7 | OEM-X-6 | SP-GND-1 | 0.85 | no route | Ground (injector output stages) | — | |
| W8 | SP-GND-1 | T12-C1-13 | 0.85 | no route | Power Ground 1 | — | |
| W9 | SP-GND-1 | T12-C1-14 | 0.85 | no route | Power Ground 2 | — | |
| W10 | OEM-X-28 | SP-0V-1 | 0.5 | no route | Ground (electronics + sensor shielding) | — | |
| W11 | OEM-X-40 | SP-0V-1 | 0.5 | no route | O2 sensor signal ground | — | |
| W12 | OEM-X-43 | SP-0V-1 | 0.5 | no route | Crank position sensor (-) | — | |
| W13 | OEM-X-44 | SP-0V-1 | 0.5 | no route | Sensor ground (IAT/ECT/TPS) | — | |
| W14 | OEM-X-71 | SP-0V-1 | 0.5 | no route | Knock sensor ground/shield | — | |
| W15 | SP-0V-1 | T12-C2-21 | 0.5 | no route | Sensor Ground | — | |
| W16 | SP-0V-1 | T12-C2-33 | 0.5 | no route | Sensor Ground | — | |
| W17 | OEM-X-59 | T12-C2-24 | 0.5 | no route | +5V sensor supply | — | |
| W18 | OEM-X-16 | T12-C2-12 | 0.5 | no route | Crank position sensor (+) | — | |
| W19 | OEM-X-17 | T12-C2-22 | 0.5 | no route | Camshaft position sensor (Hall) | — | |
| W20 | OEM-X-70 | T12-C3-31 | 0.5 | no route | Knock sensor cylinders 1-3 | — | |
| W21 | OEM-X-69 | T12-C3-32 | 0.5 | no route | Knock sensor cylinders 4-6 | — | |
| W22 | OEM-X-50 | T12-C1-10 | 0.5 | no route | Ignition coil cylinder 1 | — | |
| W23 | OEM-X-51 | T12-C1-18 | 0.5 | no route | Ignition coil cylinder 2 | — | |
| W24 | OEM-X-52 | T12-C1-1 | 0.5 | no route | Ignition coil cylinder 3 | — | |
| W25 | OEM-X-23 | T12-C1-26 | 0.5 | no route | Ignition coil cylinder 4 | — | |
| W26 | OEM-X-25 | T12-C1-11 | 0.5 | no route | Ignition coil cylinder 5 | — | |
| W27 | OEM-X-24 | T12-C1-27 | 0.5 | no route | Ignition coil cylinder 6 | — | |
| W28 | OEM-X-33 | T12-C1-9 | 0.5 | no route | Injector cylinder 1 | — | |
| W29 | OEM-X-32 | T12-C1-17 | 0.5 | no route | Injector cylinder 2 | — | |
| W30 | OEM-X-31 | T12-C1-34 | 0.5 | no route | Injector cylinder 3 | — | |
| W31 | OEM-X-5 | T12-C1-25 | 0.5 | no route | Injector cylinder 4 | — | |
| W32 | OEM-X-3 | T12-C1-16 | 0.5 | no route | Injector cylinder 5 | — | |
| W33 | OEM-X-4 | T12-C1-15 | 0.5 | no route | Injector cylinder 6 | — | |
| W34 | OEM-X-1 | T12-C1-5 | 0.5 | no route | Fuel pump relay control | — | |
| W35 | OEM-X-27 | T12-C1-4 | 0.5 | no route | Main relay control | — | |
| W36 | OEM-X-38 | T12-C3-9 | 0.5 | no route | O2 sensor heater relay control | — | |
| W37 | OEM-X-2 | T12-C1-3 | 0.5 | no route | Idle speed control valve (close winding) | — | |
| W38 | OEM-X-29 | T12-C3-22 | 0.5 | no route | Idle speed control valve (open winding) | — | |
| W39 | OEM-X-36 | T12-C3-23 | 0.5 | no route | Evap purge solenoid | — | |
| W40 | OEM-X-7 | T12-C3-24 | 0.5 | no route | VANOS intake camshaft solenoid | — | |
| W41 | OEM-X-8 | T12-C3-25 | 0.5 | no route | Check engine light (MIL) | — | |
| W42 | OEM-X-47 | T12-C3-10 | 0.5 | no route | Tachometer output | — | |
| W43 | OEM-X-41 | T12-C2-10 | 0.5 | no route | Mass air flow (MAF) signal | — | |
| W44 | OEM-X-73 | T12-C2-1 | 0.5 | no route | Throttle position (TPS) | — | |
| W45 | OEM-X-13 | T12-C2-5 | 0.5 | no route | O2 sensor signal | — | |
| W46 | OEM-X-78 | T12-C2-7 | 0.5 | no route | Engine coolant temperature (ECT) | — | |
| W47 | OEM-X-77 | T12-C2-25 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W48 | OEM-X-42 | T12-C2-2 | 0.5 | no route | Vehicle speed signal | — |
Bill of materials
| Category | Part number | Manufacturer | Description | Qty | Unit |
|---|---|---|---|---|---|
| connector | BMW-E36-DME-CONN | BMW | E36 DME (M3.1/M3.3.1) harness connector | 1.000 | ea |
ECU setup sheet
| Role | Engine ref | Engine signal | Sensor | ECU point | ECU function | ECU class | Setup flag |
|---|---|---|---|---|---|---|---|
| No configured channels. | |||||||
Findings
Open (3)
| Severity | Code | Subject | Message |
|---|---|---|---|
| error | PHYS_REQUIRED_OPEN | T12-C3-27 | T12-C3-27 "Permanent 12v" is required but not wired. |
| info | NET_FAMILY | OEM-X-47 ↔ T12-C3-10 | OEM-X-47 "Tachometer output" [tacho_out] is wired to T12-C3-10 "PWM 8" [low_side_out]. Tacho as a low-side output: check the tach needs a pull-up. |
| info | UNMAPPED | OEM | 2 optional OEM pins are not mapped: OEM-X-45 Shield ground; OEM-X-56 Ignition switch (terminal 15) |
Accepted (0)
| Code | Subject | Reason | By |
|---|
Notes
Auto-mapped by auto_map() from the library pin data on 2026-10-09. Review every wire against both manuals before building. Open items: - T12-C3 27: Permanent 12v: required by DTAFast T12 but no stock pin feeds it; wire by hand Not wired: - OEM-X 45: Shield ground: no shield pin on DTAFast T12 - OEM-X 56: Ignition switch (terminal 15): key-on 12 V sense — optional in a swap (the main relay is energized from keyed 12 V, not from this pin); DTAFast T12 has no dedicated key-on input
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | DTAFast T12+ ECU wiring diagram (served for T12 and T12+) | https://cdn.shopify.com/s/files/1/0848/7508/4108/files/T12PLUS_Wiring-Diagram.pdf?v=1728572014 | — | — | — |
| 4 | vendor_doc | Link BMWLink E36X (G4X) plug-in install manual | https://linkecu.com/documentation/E36X.pdf | archive | 2026-10-05 | 010cda3acd08 |
| 2 | community_copy | bimmer-service: Bosch Motronic M3.3.1 pinout (E36 M50) | https://www.bimmer-service.com/2025/11/17/bosch-motronic-m3-3-1-pinout-wiring-diagram/ | — | — | — |