BMW 3 Series E36 1990–2000 (M50/M52) → FuelTech FT450 (auto)
BMW 3 Series E36 1990–2000 (M50/M52) — FuelTech — FT450
⚠ NOT CHECKED. Don't build from this.
Drawn by Michael Gnankou · Rev 0 · draft · 2026-10-11
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 | 4: read the Findings page before cutting any wire |
| Size of the job | 36 wires · 5 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 | FT450-A-A13 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-X-15 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | OEM-X-34 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | OEM-X-55 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-X-6 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | SP-GND-1 | FT450-A-A7 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | OEM-X-28 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | OEM-X-40 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | OEM-X-43 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-X-44 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-X-71 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | SP-0V-1 | FT450-A-A12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-X-59 | FT450-A-A14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-X-16 | FT450-A-A18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | SP-0V-1 | FT450-A-A18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-X-17 | FT450-A-A17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-X-50 | FT450-A-A8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-X-51 | FT450-A-A9 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-X-52 | FT450-A-A10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-X-23 | FT450-A-A11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-X-33 | FT450-A-A1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-X-32 | FT450-A-A2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-X-31 | FT450-A-A1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-X-5 | FT450-A-A2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-X-3 | FT450-A-A1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-X-4 | FT450-A-A2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-X-1 | FT450-A-A6 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-X-27 | FT450-A-A3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-X-41 | FT450-A-A20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-X-73 | FT450-A-A21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-X-78 | FT450-A-A24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-X-38 | FT450-A-A4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-X-2 | FT450-A-A5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-X-13 | FT450-A-A22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-X-77 | FT450-A-A26 | 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 | FT450-A-A12 | FT450-A-A13 | open (OL) | sensor ground must not touch +12 V supply | |
| 2 | FT450-A-A12 | FT450-A-A14 | open (OL) | sensor ground must not touch 5 V sensor reference | |
| 3 | FT450-A-A13 | FT450-A-A14 | open (OL) | +12 V supply must not touch 5 V sensor reference | |
| 4 | FT450-A-A7 | FT450-A-A13 | open (OL) | power ground must not touch +12 V supply | |
| 5 | FT450-A-A7 | FT450-A-A14 | open (OL) | power ground 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
FT450-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A1 | Injector 1 (Bank A) | — | W22 | — | 0.5 | OEM-X-33 | — | — | — |
| A1 | Injector 1 (Bank A) | — | W24 | — | 0.5 | OEM-X-31 | — | — | — |
| A1 | Injector 1 (Bank A) | — | W26 | — | 0.5 | OEM-X-3 | — | — | — |
| A10 | Ignition 3 | — | W20 | — | 0.5 | OEM-X-52 | — | — | — |
| A11 | Ignition 4 | — | W21 | — | 0.5 | OEM-X-23 | — | — | — |
| A12 | Signal ground | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| A13 | +12V switched | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| A14 | +5V sensor supply | — | W14 | — | 0.5 | OEM-X-59 | — | — | — |
| A15 | CAN A LOW | — | — | — | — | — | — | — | — |
| A16 | CAN A HIGH | — | — | — | — | — | — | — | — |
| A17 | Phase input (cam) | — | W17 | — | 0.5 | OEM-X-17 | — | — | — |
| A18 | RPM reference (crank -) | — | W15 | — | 0.5 | OEM-X-16 | — | — | — |
| A18 | RPM reference (crank -) | — | W16 | — | 0.5 | SP-0V-1 | — | — | — |
| A19 | RPM signal (crank +) | — | — | — | — | — | — | — | — |
| A2 | Injector 2 (Bank A) | — | W23 | — | 0.5 | OEM-X-32 | — | — | — |
| A2 | Injector 2 (Bank A) | — | W25 | — | 0.5 | OEM-X-5 | — | — | — |
| A2 | Injector 2 (Bank A) | — | W27 | — | 0.5 | OEM-X-4 | — | — | — |
| A20 | White input 1 | — | W30 | — | 0.5 | OEM-X-41 | — | — | — |
| A21 | White input 2 | — | W31 | — | 0.5 | OEM-X-73 | — | — | — |
| A22 | White input 3 (TPS) | — | W35 | — | 0.5 | OEM-X-13 | — | — | — |
| A23 | White input 4 (oil pressure) | — | — | — | — | — | — | — | — |
| A24 | White input 5 (water temp) | — | W32 | — | 0.5 | OEM-X-78 | — | — | — |
| A25 | White input 6 (fuel pressure) | — | — | — | — | — | — | — | — |
| A26 | White input 7 (air temp) | — | W36 | — | 0.5 | OEM-X-77 | — | — | — |
| A3 | Aux 1 | — | W29 | — | 0.5 | OEM-X-27 | — | — | — |
| A4 | Aux 2 | — | W33 | — | 0.5 | OEM-X-38 | — | — | — |
| A5 | Aux 3 | — | W34 | — | 0.5 | OEM-X-2 | — | — | — |
| A6 | Aux 4 (fuel pump / relays) | — | W28 | — | 0.5 | OEM-X-1 | — | — | — |
| A7 | Power ground | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| A8 | Ignition 1 | — | W18 | — | 0.5 | OEM-X-50 | — | — | — |
| A9 | Ignition 2 | — | W19 | — | 0.5 | OEM-X-51 | — | — | — |
OEM-X
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Fuel pump relay control | — | W28 | — | 0.5 | FT450-A-A6 | — | — | — |
| 13 | O2 sensor signal | — | W35 | — | 0.5 | FT450-A-A22 | — | — | — |
| 15 | Ground | — | W3 | — | 0.85 | SP-GND-1 | — | — | — |
| 16 | Crank position sensor (+) | — | W15 | — | 0.5 | FT450-A-A18 | — | — | — |
| 17 | Camshaft position sensor (Hall) | — | W17 | — | 0.5 | FT450-A-A17 | — | — | — |
| 2 | Idle speed control valve (close winding) | — | W34 | — | 0.5 | FT450-A-A5 | — | — | — |
| 23 | Ignition coil cylinder 4 | — | W21 | — | 0.5 | FT450-A-A11 | — | — | — |
| 24 | Ignition coil cylinder 6 | — | — | — | — | — | — | — | — |
| 25 | Ignition coil cylinder 5 | — | — | — | — | — | — | — | — |
| 26 | Battery voltage (constant +12V) | — | — | — | — | — | — | — | — |
| 27 | Main relay control | — | W29 | — | 0.5 | FT450-A-A3 | — | — | — |
| 28 | Ground (electronics + sensor shielding) | — | W8 | — | 0.5 | SP-0V-1 | — | — | — |
| 29 | Idle speed control valve (open winding) | — | — | — | — | — | — | — | — |
| 3 | Injector cylinder 5 | — | W26 | — | 0.5 | FT450-A-A1 | — | — | — |
| 31 | Injector cylinder 3 | — | W24 | — | 0.5 | FT450-A-A1 | — | — | — |
| 32 | Injector cylinder 2 | — | W23 | — | 0.5 | FT450-A-A2 | — | — | — |
| 33 | Injector cylinder 1 | — | W22 | — | 0.5 | FT450-A-A1 | — | — | — |
| 34 | Ground (output stages) | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| 36 | Evap purge solenoid | — | — | — | — | — | — | — | — |
| 38 | O2 sensor heater relay control | — | W33 | — | 0.5 | FT450-A-A4 | — | — | — |
| 4 | Injector cylinder 6 | — | W27 | — | 0.5 | FT450-A-A2 | — | — | — |
| 40 | O2 sensor signal ground | — | W9 | — | 0.5 | SP-0V-1 | — | — | — |
| 41 | Mass air flow (MAF) signal | — | W30 | — | 0.5 | FT450-A-A20 | — | — | — |
| 42 | Vehicle speed signal | — | — | — | — | — | — | — | — |
| 43 | Crank position sensor (-) | — | W10 | — | 0.5 | SP-0V-1 | — | — | — |
| 44 | Sensor ground (IAT/ECT/TPS) | — | W11 | — | 0.5 | SP-0V-1 | — | — | — |
| 45 | Shield ground | — | — | — | — | — | — | — | — |
| 47 | Tachometer output | — | — | — | — | — | — | — | — |
| 5 | Injector cylinder 4 | — | W25 | — | 0.5 | FT450-A-A2 | — | — | — |
| 50 | Ignition coil cylinder 1 | — | W18 | — | 0.5 | FT450-A-A8 | — | — | — |
| 51 | Ignition coil cylinder 2 | — | W19 | — | 0.5 | FT450-A-A9 | — | — | — |
| 52 | Ignition coil cylinder 3 | — | W20 | — | 0.5 | FT450-A-A10 | — | — | — |
| 54 | ECU power (+14V from main relay) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| 55 | Ground (ignition) | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| 56 | Ignition switch (terminal 15) | — | — | — | — | — | — | — | — |
| 59 | +5V sensor supply | — | W14 | — | 0.5 | FT450-A-A14 | — | — | — |
| 6 | Ground (injector output stages) | — | W6 | — | 0.85 | SP-GND-1 | — | — | — |
| 69 | Knock sensor cylinders 4-6 | — | — | — | — | — | — | — | — |
| 7 | VANOS intake camshaft solenoid | — | — | — | — | — | — | — | — |
| 70 | Knock sensor cylinders 1-3 | — | — | — | — | — | — | — | — |
| 71 | Knock sensor ground/shield | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| 73 | Throttle position (TPS) | — | W31 | — | 0.5 | FT450-A-A21 | — | — | — |
| 77 | Intake air temperature (IAT) | — | W36 | — | 0.5 | FT450-A-A26 | — | — | — |
| 78 | Engine coolant temperature (ECT) | — | W32 | — | 0.5 | FT450-A-A24 | — | — | — |
| 8 | Check engine light (MIL) | — | — | — | — | — | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W8 | — | 0.5 | OEM-X-28 | — | — | — |
| 1 | — | — | W9 | — | 0.5 | OEM-X-40 | — | — | — |
| 1 | — | — | W10 | — | 0.5 | OEM-X-43 | — | — | — |
| 1 | — | — | W11 | — | 0.5 | OEM-X-44 | — | — | — |
| 1 | — | — | W12 | — | 0.5 | OEM-X-71 | — | — | — |
| 1 | — | — | W13 | — | 0.5 | FT450-A-A12 | — | — | — |
| 1 | — | — | W16 | — | 0.5 | FT450-A-A18 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-X-54 | — | — | — |
| 1 | — | — | W2 | — | 0.85 | FT450-A-A13 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W3 | — | 0.85 | OEM-X-15 | — | — | — |
| 1 | — | — | W4 | — | 0.85 | OEM-X-34 | — | — | — |
| 1 | — | — | W5 | — | 0.85 | OEM-X-55 | — | — | — |
| 1 | — | — | W6 | — | 0.85 | OEM-X-6 | — | — | — |
| 1 | — | — | W7 | — | 0.85 | FT450-A-A7 | — | — | — |
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 | FT450-A-A6 | Aux 4 (fuel pump / relays) | low_side_out | corroborated | |
| OEM-X-13 | O2 sensor signal | lambda_nb_in | FT450-A-A22 | White input 3 (TPS) | analog_in | corroborated | |
| OEM-X-15 | Ground | ground | FT450-A-A7 | Power ground | ground | corroborated | |
| OEM-X-16 | Crank position sensor (+) | trigger_in | FT450-A-A12 + FT450-A-A18 | Signal ground + RPM reference (crank -) | sensor_ground + trigger_in | corroborated | |
| OEM-X-17 | Camshaft position sensor (Hall) | trigger_in | FT450-A-A17 | Phase input (cam) | trigger_in | corroborated | |
| OEM-X-2 | Idle speed control valve (close winding) | low_side_out | FT450-A-A5 | Aux 3 | low_side_out | corroborated | |
| OEM-X-23 | Ignition coil cylinder 4 | ignition_out | FT450-A-A11 | Ignition 4 | ignition_out | corroborated | |
| OEM-X-24 | Ignition coil cylinder 6 | ignition_out | — | — | — | corroborated | |
| OEM-X-25 | Ignition coil cylinder 5 | ignition_out | — | — | — | corroborated | |
| OEM-X-26 | Battery voltage (constant +12V) | power_in | — | — | — | corroborated | |
| OEM-X-27 | Main relay control | low_side_out | FT450-A-A3 | Aux 1 | low_side_out | corroborated | |
| OEM-X-28 | Ground (electronics + sensor shielding) | sensor_ground | FT450-A-A12 + FT450-A-A18 | Signal ground + RPM reference (crank -) | sensor_ground + trigger_in | corroborated | |
| OEM-X-29 | Idle speed control valve (open winding) | low_side_out | — | — | — | corroborated | |
| OEM-X-3 | Injector cylinder 5 | injector_out | FT450-A-A1 | Injector 1 (Bank A) | injector_out | corroborated | |
| OEM-X-31 | Injector cylinder 3 | injector_out | FT450-A-A1 | Injector 1 (Bank A) | injector_out | corroborated | |
| OEM-X-32 | Injector cylinder 2 | injector_out | FT450-A-A2 | Injector 2 (Bank A) | injector_out | corroborated | |
| OEM-X-33 | Injector cylinder 1 | injector_out | FT450-A-A1 | Injector 1 (Bank A) | injector_out | corroborated | |
| OEM-X-34 | Ground (output stages) | ground | FT450-A-A7 | Power ground | ground | corroborated | |
| OEM-X-36 | Evap purge solenoid | low_side_out | — | — | — | corroborated | |
| OEM-X-38 | O2 sensor heater relay control | low_side_out | FT450-A-A4 | Aux 2 | low_side_out | corroborated | |
| OEM-X-4 | Injector cylinder 6 | injector_out | FT450-A-A2 | Injector 2 (Bank A) | injector_out | corroborated | |
| OEM-X-40 | O2 sensor signal ground | sensor_ground | FT450-A-A12 + FT450-A-A18 | Signal ground + RPM reference (crank -) | sensor_ground + trigger_in | corroborated | |
| OEM-X-41 | Mass air flow (MAF) signal | analog_in | FT450-A-A20 | White input 1 | analog_in | corroborated | |
| OEM-X-42 | Vehicle speed signal | digital_in | — | — | — | corroborated | |
| OEM-X-43 | Crank position sensor (-) | sensor_ground | FT450-A-A12 + FT450-A-A18 | Signal ground + RPM reference (crank -) | sensor_ground + trigger_in | corroborated | |
| OEM-X-44 | Sensor ground (IAT/ECT/TPS) | sensor_ground | FT450-A-A12 + FT450-A-A18 | Signal ground + RPM reference (crank -) | sensor_ground + trigger_in | corroborated | |
| OEM-X-45 | Shield ground | shield | — | — | — | corroborated | |
| OEM-X-47 | Tachometer output | tacho_out | — | — | — | corroborated | |
| OEM-X-5 | Injector cylinder 4 | injector_out | FT450-A-A2 | Injector 2 (Bank A) | injector_out | corroborated | |
| OEM-X-50 | Ignition coil cylinder 1 | ignition_out | FT450-A-A8 | Ignition 1 | ignition_out | corroborated | |
| OEM-X-51 | Ignition coil cylinder 2 | ignition_out | FT450-A-A9 | Ignition 2 | ignition_out | corroborated | |
| OEM-X-52 | Ignition coil cylinder 3 | ignition_out | FT450-A-A10 | Ignition 3 | ignition_out | corroborated | |
| OEM-X-54 | ECU power (+14V from main relay) | power_in | FT450-A-A13 | +12V switched | power_in | corroborated | |
| OEM-X-55 | Ground (ignition) | ground | FT450-A-A7 | Power ground | ground | corroborated | |
| OEM-X-56 | Ignition switch (terminal 15) | digital_in | — | — | — | corroborated | |
| OEM-X-59 | +5V sensor supply | vref | FT450-A-A14 | +5V sensor supply | vref | corroborated | |
| OEM-X-6 | Ground (injector output stages) | ground | FT450-A-A7 | Power ground | ground | corroborated | |
| OEM-X-69 | Knock sensor cylinders 4-6 | knock_in | — | — | — | corroborated | |
| OEM-X-7 | VANOS intake camshaft solenoid | low_side_out | — | — | — | corroborated | |
| OEM-X-70 | Knock sensor cylinders 1-3 | knock_in | — | — | — | corroborated | |
| OEM-X-71 | Knock sensor ground/shield | sensor_ground | FT450-A-A12 + FT450-A-A18 | Signal ground + RPM reference (crank -) | sensor_ground + trigger_in | corroborated | |
| OEM-X-73 | Throttle position (TPS) | analog_in | FT450-A-A21 | White input 2 | analog_in | corroborated | |
| OEM-X-77 | Intake air temperature (IAT) | temp_in | FT450-A-A26 | White input 7 (air temp) | temp_in | corroborated | |
| OEM-X-78 | Engine coolant temperature (ECT) | temp_in | FT450-A-A24 | White input 5 (water temp) | temp_in | corroborated | |
| OEM-X-8 | Check engine light (MIL) | 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 | FT450-A-A13 | 0.85 | no route | +12V switched | — | |
| W3 | OEM-X-15 | SP-GND-1 | 0.85 | no route | Ground | — | |
| W4 | OEM-X-34 | SP-GND-1 | 0.85 | no route | Ground (output stages) | — | |
| W5 | OEM-X-55 | SP-GND-1 | 0.85 | no route | Ground (ignition) | — | |
| W6 | OEM-X-6 | SP-GND-1 | 0.85 | no route | Ground (injector output stages) | — | |
| W7 | SP-GND-1 | FT450-A-A7 | 0.85 | no route | Power ground | — | |
| W8 | OEM-X-28 | SP-0V-1 | 0.5 | no route | Ground (electronics + sensor shielding) | — | |
| W9 | OEM-X-40 | SP-0V-1 | 0.5 | no route | O2 sensor signal ground | — | |
| W10 | OEM-X-43 | SP-0V-1 | 0.5 | no route | Crank position sensor (-) | — | |
| W11 | OEM-X-44 | SP-0V-1 | 0.5 | no route | Sensor ground (IAT/ECT/TPS) | — | |
| W12 | OEM-X-71 | SP-0V-1 | 0.5 | no route | Knock sensor ground/shield | — | |
| W13 | SP-0V-1 | FT450-A-A12 | 0.5 | no route | Signal ground | — | |
| W14 | OEM-X-59 | FT450-A-A14 | 0.5 | no route | +5V sensor supply | — | |
| W15 | OEM-X-16 | FT450-A-A18 | 0.5 | no route | Crank position sensor (+) | — | |
| W16 | SP-0V-1 | FT450-A-A18 | 0.5 | no route | RPM reference (crank -) | — | |
| W17 | OEM-X-17 | FT450-A-A17 | 0.5 | no route | Camshaft position sensor (Hall) | — | |
| W18 | OEM-X-50 | FT450-A-A8 | 0.5 | no route | Ignition coil cylinder 1 | — | |
| W19 | OEM-X-51 | FT450-A-A9 | 0.5 | no route | Ignition coil cylinder 2 | — | |
| W20 | OEM-X-52 | FT450-A-A10 | 0.5 | no route | Ignition coil cylinder 3 | — | |
| W21 | OEM-X-23 | FT450-A-A11 | 0.5 | no route | Ignition coil cylinder 4 | — | |
| W22 | OEM-X-33 | FT450-A-A1 | 0.5 | no route | Injector cylinder 1 | — | |
| W23 | OEM-X-32 | FT450-A-A2 | 0.5 | no route | Injector cylinder 2 | — | |
| W24 | OEM-X-31 | FT450-A-A1 | 0.5 | no route | Injector cylinder 3 | — | |
| W25 | OEM-X-5 | FT450-A-A2 | 0.5 | no route | Injector cylinder 4 | — | |
| W26 | OEM-X-3 | FT450-A-A1 | 0.5 | no route | Injector cylinder 5 | — | |
| W27 | OEM-X-4 | FT450-A-A2 | 0.5 | no route | Injector cylinder 6 | — | |
| W28 | OEM-X-1 | FT450-A-A6 | 0.5 | no route | Fuel pump relay control | — | |
| W29 | OEM-X-27 | FT450-A-A3 | 0.5 | no route | Main relay control | — | |
| W30 | OEM-X-41 | FT450-A-A20 | 0.5 | no route | Mass air flow (MAF) signal | — | |
| W31 | OEM-X-73 | FT450-A-A21 | 0.5 | no route | Throttle position (TPS) | — | |
| W32 | OEM-X-78 | FT450-A-A24 | 0.5 | no route | Engine coolant temperature (ECT) | — | |
| W33 | OEM-X-38 | FT450-A-A4 | 0.5 | no route | O2 sensor heater relay control | — | |
| W34 | OEM-X-2 | FT450-A-A5 | 0.5 | no route | Idle speed control valve (close winding) | — | |
| W35 | OEM-X-13 | FT450-A-A22 | 0.5 | no route | O2 sensor signal | — | |
| W36 | OEM-X-77 | FT450-A-A26 | 0.5 | no route | Intake air temperature (IAT) | — |
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 (6)
| Severity | Code | Subject | Message |
|---|---|---|---|
| error | NET_MERGED | FT450-A-A1 + OEM-X-3 + OEM-X-31 + OEM-X-33 | 3 different OEM functions share one net: OEM-X-3 Injector cylinder 5; OEM-X-31 Injector cylinder 3; OEM-X-33 Injector cylinder 1 |
| error | NET_MERGED | FT450-A-A2 + OEM-X-32 + OEM-X-4 + OEM-X-5 | 3 different OEM functions share one net: OEM-X-32 Injector cylinder 2; OEM-X-4 Injector cylinder 6; OEM-X-5 Injector cylinder 4 |
| error | REQUIRED_UNMAPPED | OEM-X-24 | Required OEM function "Ignition coil cylinder 6" (ignition_out) is not connected to the new ECU. |
| error | REQUIRED_UNMAPPED | OEM-X-25 | Required OEM function "Ignition coil cylinder 5" (ignition_out) is not connected to the new ECU. |
| info | NET_FAMILY | OEM-X-16 ↔ OEM-X-28 | OEM-X-16 "Crank position sensor (+)" [trigger_in] is wired to OEM-X-28 "Ground (electronics + sensor shielding)" [sensor_ground]. Trigger return tied to sensor/trigger ground: correct for single-ended trigger inputs. |
| info | UNMAPPED | OEM | 10 optional OEM pins are not mapped: OEM-X-29 Idle speed control valve (open winding); OEM-X-36 Evap purge solenoid; OEM-X-42 Vehicle speed signal; OEM-X-45 Shield ground; OEM-X-47 Tachometer output; OEM-X-56 Ignition switch (terminal 15); OEM-X-69 Knock sensor cylinders 4-6; OEM-X-7 VANOS intake camshaft solenoid; OEM-X-70 Knock sensor cylinders 1-3; OEM-X-8 Check engine light (MIL) |
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-X-26 | Battery-constant (memory) feed of the stock ECU: the new ECU has no such input, so it is not needed. | mapping-proposal |
Notes
Auto-mapped by auto_map() from the library pin data on 2026-10-11. Review every wire against both manuals before building. Open items: - OEM-X 25: Ignition coil cylinder 5: no free ignition output on FuelTech FT450 - OEM-X 24: Ignition coil cylinder 6: no free ignition output on FuelTech FT450 Not wired: - OEM-X 26: Battery voltage (constant +12V): FuelTech FT450 has no battery-constant input; not needed - OEM-X 70: Knock sensor cylinders 1-3: no free knock input on FuelTech FT450 - OEM-X 69: Knock sensor cylinders 4-6: no free knock input on FuelTech FT450 - OEM-X 45: Shield ground: no shield pin on FuelTech FT450 - 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); FuelTech FT450 has no dedicated key-on input - OEM-X 29: Idle speed control valve (open winding): no free low_side/relay_control/heater_low_side/ls_hs/injector on FuelTech FT450 - OEM-X 36: Evap purge solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on FuelTech FT450 - OEM-X 7: VANOS intake camshaft solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on FuelTech FT450 - OEM-X 8: Check engine light (MIL): no free low_side/relay_control/heater_low_side/ls_hs/injector on FuelTech FT450 - OEM-X 47: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on FuelTech FT450 - OEM-X 42: Vehicle speed signal: no free frequency_in/switch_in on FuelTech FT450
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | FuelTech FT450/FT550 ready harness manual (4 & 6 cylinder) — FT450 Connector A pinout | http://ftmanager.fueltech.com.br/downloads/manual/Portugues/Chicote_pronto_FT450-FT550.pdf | — | — | — |
| 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/ | — | — | — |