BMW 3 Series E36 1990–2000 (M50/M52) → MaxxECU MaxxECU STREET REV9+ (auto)
BMW 3 Series E36 1990–2000 (M50/M52) — MaxxECU — MaxxECU STREET
Drawn by Michael Gnankou · Rev 0 · proposal · 2026-10-08
Before you start
| Status | proposal · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | none |
| Size of the job | 42 wires · 6 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 | MAXXECUSTREE-C1-M4 | 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 | MAXXECUSTREE-C1-L4 | 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 | MAXXECUSTREE-C1-H1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | SP-0V-1 | MAXXECUSTREE-C1-H2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-X-59 | MAXXECUSTREE-C1-G1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | OEM-X-16 | MAXXECUSTREE-C1-H3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-X-17 | MAXXECUSTREE-C1-H4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-X-50 | MAXXECUSTREE-C1-A2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-X-51 | MAXXECUSTREE-C1-A3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-X-52 | MAXXECUSTREE-C1-B2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-X-23 | MAXXECUSTREE-C1-B3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-X-25 | MAXXECUSTREE-C1-C2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-X-24 | MAXXECUSTREE-C1-C3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-X-33 | MAXXECUSTREE-C1-K1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-X-32 | MAXXECUSTREE-C1-K2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-X-31 | MAXXECUSTREE-C1-M1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-X-5 | MAXXECUSTREE-C1-M2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-X-3 | MAXXECUSTREE-C1-M3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-X-4 | MAXXECUSTREE-C1-L3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-X-45 | SP-SHD-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | SP-SHD-1 | MAXXECUSTREE-C1-E3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-X-1 | MAXXECUSTREE-C1-B4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-X-27 | MAXXECUSTREE-C1-C4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-X-38 | MAXXECUSTREE-C1-D1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-X-2 | MAXXECUSTREE-C1-D4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-X-29 | MAXXECUSTREE-C1-A4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-X-41 | MAXXECUSTREE-C1-J3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-X-73 | MAXXECUSTREE-C1-G2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-X-13 | MAXXECUSTREE-C1-J4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-X-78 | MAXXECUSTREE-C1-J1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-X-77 | MAXXECUSTREE-C1-J2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W42 | OEM-X-42 | MAXXECUSTREE-C1-K3 | 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 | MAXXECUSTREE-C1-H1 | MAXXECUSTREE-C1-G1 | open (OL) | sensor ground must not touch 5 V sensor reference | |
| 2 | MAXXECUSTREE-C1-H1 | MAXXECUSTREE-C1-M4 | open (OL) | sensor ground must not touch +12 V supply | |
| 3 | MAXXECUSTREE-C1-L4 | MAXXECUSTREE-C1-G1 | open (OL) | power ground must not touch 5 V sensor reference | |
| 4 | MAXXECUSTREE-C1-L4 | MAXXECUSTREE-C1-M4 | open (OL) | power ground must not touch +12 V supply | |
| 5 | MAXXECUSTREE-C1-M4 | MAXXECUSTREE-C1-G1 | open (OL) | +12 V supply must not touch 5 V sensor reference |
Revisions
| Rev | Label | By | Date |
|---|---|---|---|
| No revisions yet. | |||
Schematic
Connectors
MAXXECUSTREE-C1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A2 | IGN 1 | — | W18 | — | 0.5 | OEM-X-50 | — | — | — |
| A3 | IGN 2 | — | W19 | — | 0.5 | OEM-X-51 | — | — | — |
| A4 | GPO 8/TACHO | — | W36 | — | 0.5 | OEM-X-29 | — | — | — |
| B2 | IGN 3 | — | W20 | — | 0.5 | OEM-X-52 | — | — | — |
| B3 | IGN 4 | — | W21 | — | 0.5 | OEM-X-23 | — | — | — |
| B4 | GPO 1 | — | W32 | — | 0.5 | OEM-X-1 | — | — | — |
| C2 | IGN 5 | — | W22 | — | 0.5 | OEM-X-25 | — | — | — |
| C3 | IGN 6 | — | W23 | — | 0.5 | OEM-X-24 | — | — | — |
| C4 | GPO 2 | — | W33 | — | 0.5 | OEM-X-27 | — | — | — |
| D1 | WBO2 Heater- | — | W34 | — | 0.5 | OEM-X-38 | — | — | — |
| D4 | GPO 3 | — | W35 | — | 0.5 | OEM-X-2 | — | — | — |
| E1 | CAN H | — | — | — | — | — | — | — | — |
| E2 | CAN L | — | — | — | — | — | — | — | — |
| E3 | GND Shield | — | W31 | — | 0.5 | SP-SHD-1 | — | — | — |
| F1 | CLT | — | — | — | — | — | — | — | — |
| F2 | IAT | — | — | — | — | — | — | — | — |
| F3 | WBO2 VREF | — | — | — | — | — | — | — | — |
| F4 | WBO2 VS | — | — | — | — | — | — | — | — |
| G1 | +5V sensor supply | — | W15 | — | 0.5 | OEM-X-59 | — | — | — |
| G2 | TPS/AIN | — | W38 | — | 0.5 | OEM-X-73 | — | — | — |
| G3 | WBO2 IP | — | — | — | — | — | — | — | — |
| G4 | WBO2 RCAL | — | — | — | — | — | — | — | — |
| H1 | Sensor GND | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| H2 | Trigger GND | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| H3 | TRIGGER | — | W16 | — | 0.5 | OEM-X-16 | — | — | — |
| H4 | HOME | — | W17 | — | 0.5 | OEM-X-17 | — | — | — |
| J1 | AIN 1 (temperature) | — | W40 | — | 0.5 | OEM-X-78 | — | — | — |
| J2 | AIN 2 (Temperature) | — | W41 | — | 0.5 | OEM-X-77 | — | — | — |
| J3 | AIN 3 (0-5V) | — | W37 | — | 0.5 | OEM-X-41 | — | — | — |
| J4 | AIN 4 (0-5V) | — | W39 | — | 0.5 | OEM-X-13 | — | — | — |
| K1 | INJ 1 | — | W24 | — | 0.5 | OEM-X-33 | — | — | — |
| K2 | INJ 2 | — | W25 | — | 0.5 | OEM-X-32 | — | — | — |
| K3 | DIN 1 | — | W42 | — | 0.5 | OEM-X-42 | — | — | — |
| K4 | DIN 2 | — | — | — | — | — | — | — | — |
| L3 | INJ 6 | — | W29 | — | 0.5 | OEM-X-4 | — | — | — |
| L4 | Engine GND | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| M1 | INJ 3 | — | W26 | — | 0.5 | OEM-X-31 | — | — | — |
| M2 | INJ 4 | — | W27 | — | 0.5 | OEM-X-5 | — | — | — |
| M3 | INJ 5 | — | W28 | — | 0.5 | OEM-X-3 | — | — | — |
| M4 | +12V ECU power supply | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
OEM-X
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Fuel pump relay control | — | W32 | — | 0.5 | MAXXECUSTREE-C1-B4 | — | — | — |
| 13 | O2 sensor signal | — | W39 | — | 0.5 | MAXXECUSTREE-C1-J4 | — | — | — |
| 15 | Ground | — | W3 | — | 0.85 | SP-GND-1 | — | — | — |
| 16 | Crank position sensor (+) | — | W16 | — | 0.5 | MAXXECUSTREE-C1-H3 | — | — | — |
| 17 | Camshaft position sensor (Hall) | — | W17 | — | 0.5 | MAXXECUSTREE-C1-H4 | — | — | — |
| 2 | Idle speed control valve (close winding) | — | W35 | — | 0.5 | MAXXECUSTREE-C1-D4 | — | — | — |
| 23 | Ignition coil cylinder 4 | — | W21 | — | 0.5 | MAXXECUSTREE-C1-B3 | — | — | — |
| 24 | Ignition coil cylinder 6 | — | W23 | — | 0.5 | MAXXECUSTREE-C1-C3 | — | — | — |
| 25 | Ignition coil cylinder 5 | — | W22 | — | 0.5 | MAXXECUSTREE-C1-C2 | — | — | — |
| 26 | Battery voltage (constant +12V) | — | — | — | — | — | — | — | — |
| 27 | Main relay control | — | W33 | — | 0.5 | MAXXECUSTREE-C1-C4 | — | — | — |
| 28 | Ground (electronics + sensor shielding) | — | W8 | — | 0.5 | SP-0V-1 | — | — | — |
| 29 | Idle speed control valve (open winding) | — | W36 | — | 0.5 | MAXXECUSTREE-C1-A4 | — | — | — |
| 3 | Injector cylinder 5 | — | W28 | — | 0.5 | MAXXECUSTREE-C1-M3 | — | — | — |
| 31 | Injector cylinder 3 | — | W26 | — | 0.5 | MAXXECUSTREE-C1-M1 | — | — | — |
| 32 | Injector cylinder 2 | — | W25 | — | 0.5 | MAXXECUSTREE-C1-K2 | — | — | — |
| 33 | Injector cylinder 1 | — | W24 | — | 0.5 | MAXXECUSTREE-C1-K1 | — | — | — |
| 34 | Ground (output stages) | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| 36 | Evap purge solenoid | — | — | — | — | — | — | — | — |
| 38 | O2 sensor heater relay control | — | W34 | — | 0.5 | MAXXECUSTREE-C1-D1 | — | — | — |
| 4 | Injector cylinder 6 | — | W29 | — | 0.5 | MAXXECUSTREE-C1-L3 | — | — | — |
| 40 | O2 sensor signal ground | — | W9 | — | 0.5 | SP-0V-1 | — | — | — |
| 41 | Mass air flow (MAF) signal | — | W37 | — | 0.5 | MAXXECUSTREE-C1-J3 | — | — | — |
| 42 | Vehicle speed signal | — | W42 | — | 0.5 | MAXXECUSTREE-C1-K3 | — | — | — |
| 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 | — | W30 | — | 0.5 | SP-SHD-1 | — | — | — |
| 47 | Tachometer output | — | — | — | — | — | — | — | — |
| 5 | Injector cylinder 4 | — | W27 | — | 0.5 | MAXXECUSTREE-C1-M2 | — | — | — |
| 50 | Ignition coil cylinder 1 | — | W18 | — | 0.5 | MAXXECUSTREE-C1-A2 | — | — | — |
| 51 | Ignition coil cylinder 2 | — | W19 | — | 0.5 | MAXXECUSTREE-C1-A3 | — | — | — |
| 52 | Ignition coil cylinder 3 | — | W20 | — | 0.5 | MAXXECUSTREE-C1-B2 | — | — | — |
| 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 | — | W15 | — | 0.5 | MAXXECUSTREE-C1-G1 | — | — | — |
| 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) | — | W38 | — | 0.5 | MAXXECUSTREE-C1-G2 | — | — | — |
| 77 | Intake air temperature (IAT) | — | W41 | — | 0.5 | MAXXECUSTREE-C1-J2 | — | — | — |
| 78 | Engine coolant temperature (ECT) | — | W40 | — | 0.5 | MAXXECUSTREE-C1-J1 | — | — | — |
| 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 | MAXXECUSTREE-C1-H1 | — | — | — |
| 1 | — | — | W14 | — | 0.5 | MAXXECUSTREE-C1-H2 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-X-54 | — | — | — |
| 1 | — | — | W2 | — | 0.85 | MAXXECUSTREE-C1-M4 | — | — | — |
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 | MAXXECUSTREE-C1-L4 | — | — | — |
SP-SHD
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W30 | — | 0.5 | OEM-X-45 | — | — | — |
| 1 | — | — | W31 | — | 0.5 | MAXXECUSTREE-C1-E3 | — | — | — |
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 | MAXXECUSTREE-C1-B4 | GPO 1 | low_side_out | corroborated | |
| OEM-X-13 | O2 sensor signal | lambda_nb_in | MAXXECUSTREE-C1-J4 | AIN 4 (0-5V) | analog_in | corroborated | |
| OEM-X-15 | Ground | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | corroborated | |
| OEM-X-16 | Crank position sensor (+) | trigger_in | MAXXECUSTREE-C1-H3 | TRIGGER | trigger_in | corroborated | |
| OEM-X-17 | Camshaft position sensor (Hall) | trigger_in | MAXXECUSTREE-C1-H4 | HOME | trigger_in | corroborated | |
| OEM-X-2 | Idle speed control valve (close winding) | low_side_out | MAXXECUSTREE-C1-D4 | GPO 3 | low_side_out | corroborated | |
| OEM-X-23 | Ignition coil cylinder 4 | ignition_out | MAXXECUSTREE-C1-B3 | IGN 4 | ignition_out | corroborated | |
| OEM-X-24 | Ignition coil cylinder 6 | ignition_out | MAXXECUSTREE-C1-C3 | IGN 6 | ignition_out | corroborated | |
| OEM-X-25 | Ignition coil cylinder 5 | ignition_out | MAXXECUSTREE-C1-C2 | IGN 5 | ignition_out | corroborated | |
| OEM-X-26 | Battery voltage (constant +12V) | power_in | — | — | — | corroborated | |
| OEM-X-27 | Main relay control | low_side_out | MAXXECUSTREE-C1-C4 | GPO 2 | low_side_out | corroborated | |
| OEM-X-28 | Ground (electronics + sensor shielding) | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | corroborated | |
| OEM-X-29 | Idle speed control valve (open winding) | low_side_out | MAXXECUSTREE-C1-A4 | GPO 8/TACHO | low_side_out | corroborated | |
| OEM-X-3 | Injector cylinder 5 | injector_out | MAXXECUSTREE-C1-M3 | INJ 5 | injector_out | corroborated | |
| OEM-X-31 | Injector cylinder 3 | injector_out | MAXXECUSTREE-C1-M1 | INJ 3 | injector_out | corroborated | |
| OEM-X-32 | Injector cylinder 2 | injector_out | MAXXECUSTREE-C1-K2 | INJ 2 | injector_out | corroborated | |
| OEM-X-33 | Injector cylinder 1 | injector_out | MAXXECUSTREE-C1-K1 | INJ 1 | injector_out | corroborated | |
| OEM-X-34 | Ground (output stages) | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | corroborated | |
| OEM-X-36 | Evap purge solenoid | low_side_out | — | — | — | corroborated | |
| OEM-X-38 | O2 sensor heater relay control | low_side_out | MAXXECUSTREE-C1-D1 | WBO2 Heater- | low_side_out | corroborated | |
| OEM-X-4 | Injector cylinder 6 | injector_out | MAXXECUSTREE-C1-L3 | INJ 6 | injector_out | corroborated | |
| OEM-X-40 | O2 sensor signal ground | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | corroborated | |
| OEM-X-41 | Mass air flow (MAF) signal | analog_in | MAXXECUSTREE-C1-J3 | AIN 3 (0-5V) | analog_in | corroborated | |
| OEM-X-42 | Vehicle speed signal | digital_in | MAXXECUSTREE-C1-K3 | DIN 1 | digital_in | corroborated | |
| OEM-X-43 | Crank position sensor (-) | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | corroborated | |
| OEM-X-44 | Sensor ground (IAT/ECT/TPS) | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | corroborated | |
| OEM-X-45 | Shield ground | shield | MAXXECUSTREE-C1-E3 | GND Shield | shield | corroborated | |
| OEM-X-47 | Tachometer output | tacho_out | — | — | — | corroborated | |
| OEM-X-5 | Injector cylinder 4 | injector_out | MAXXECUSTREE-C1-M2 | INJ 4 | injector_out | corroborated | |
| OEM-X-50 | Ignition coil cylinder 1 | ignition_out | MAXXECUSTREE-C1-A2 | IGN 1 | ignition_out | corroborated | |
| OEM-X-51 | Ignition coil cylinder 2 | ignition_out | MAXXECUSTREE-C1-A3 | IGN 2 | ignition_out | corroborated | |
| OEM-X-52 | Ignition coil cylinder 3 | ignition_out | MAXXECUSTREE-C1-B2 | IGN 3 | ignition_out | corroborated | |
| OEM-X-54 | ECU power (+14V from main relay) | power_in | MAXXECUSTREE-C1-M4 | +12V ECU power supply | power_in | corroborated | |
| OEM-X-55 | Ground (ignition) | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | corroborated | |
| OEM-X-56 | Ignition switch (terminal 15) | digital_in | — | — | — | corroborated | |
| OEM-X-59 | +5V sensor supply | vref | MAXXECUSTREE-C1-G1 | +5V sensor supply | vref | corroborated | |
| OEM-X-6 | Ground (injector output stages) | ground | MAXXECUSTREE-C1-L4 | Engine GND | 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 | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | corroborated | |
| OEM-X-73 | Throttle position (TPS) | analog_in | MAXXECUSTREE-C1-G2 | TPS/AIN | analog_in | corroborated | |
| OEM-X-77 | Intake air temperature (IAT) | temp_in | MAXXECUSTREE-C1-J2 | AIN 2 (Temperature) | temp_in | corroborated | |
| OEM-X-78 | Engine coolant temperature (ECT) | temp_in | MAXXECUSTREE-C1-J1 | AIN 1 (temperature) | 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 | MAXXECUSTREE-C1-M4 | 0.85 | no route | +12V ECU power supply | — | |
| 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 | MAXXECUSTREE-C1-L4 | 0.85 | no route | Engine GND | — | |
| 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 | MAXXECUSTREE-C1-H1 | 0.5 | no route | Sensor GND | — | |
| W14 | SP-0V-1 | MAXXECUSTREE-C1-H2 | 0.5 | no route | Trigger GND | — | |
| W15 | OEM-X-59 | MAXXECUSTREE-C1-G1 | 0.5 | no route | +5V sensor supply | — | |
| W16 | OEM-X-16 | MAXXECUSTREE-C1-H3 | 0.5 | no route | Crank position sensor (+) | — | |
| W17 | OEM-X-17 | MAXXECUSTREE-C1-H4 | 0.5 | no route | Camshaft position sensor (Hall) | — | |
| W18 | OEM-X-50 | MAXXECUSTREE-C1-A2 | 0.5 | no route | Ignition coil cylinder 1 | — | |
| W19 | OEM-X-51 | MAXXECUSTREE-C1-A3 | 0.5 | no route | Ignition coil cylinder 2 | — | |
| W20 | OEM-X-52 | MAXXECUSTREE-C1-B2 | 0.5 | no route | Ignition coil cylinder 3 | — | |
| W21 | OEM-X-23 | MAXXECUSTREE-C1-B3 | 0.5 | no route | Ignition coil cylinder 4 | — | |
| W22 | OEM-X-25 | MAXXECUSTREE-C1-C2 | 0.5 | no route | Ignition coil cylinder 5 | — | |
| W23 | OEM-X-24 | MAXXECUSTREE-C1-C3 | 0.5 | no route | Ignition coil cylinder 6 | — | |
| W24 | OEM-X-33 | MAXXECUSTREE-C1-K1 | 0.5 | no route | Injector cylinder 1 | — | |
| W25 | OEM-X-32 | MAXXECUSTREE-C1-K2 | 0.5 | no route | Injector cylinder 2 | — | |
| W26 | OEM-X-31 | MAXXECUSTREE-C1-M1 | 0.5 | no route | Injector cylinder 3 | — | |
| W27 | OEM-X-5 | MAXXECUSTREE-C1-M2 | 0.5 | no route | Injector cylinder 4 | — | |
| W28 | OEM-X-3 | MAXXECUSTREE-C1-M3 | 0.5 | no route | Injector cylinder 5 | — | |
| W29 | OEM-X-4 | MAXXECUSTREE-C1-L3 | 0.5 | no route | Injector cylinder 6 | — | |
| W30 | OEM-X-45 | SP-SHD-1 | 0.5 | no route | Shield ground | — | |
| W31 | SP-SHD-1 | MAXXECUSTREE-C1-E3 | 0.5 | no route | GND Shield | — | |
| W32 | OEM-X-1 | MAXXECUSTREE-C1-B4 | 0.5 | no route | Fuel pump relay control | — | |
| W33 | OEM-X-27 | MAXXECUSTREE-C1-C4 | 0.5 | no route | Main relay control | — | |
| W34 | OEM-X-38 | MAXXECUSTREE-C1-D1 | 0.5 | no route | O2 sensor heater relay control | — | |
| W35 | OEM-X-2 | MAXXECUSTREE-C1-D4 | 0.5 | no route | Idle speed control valve (close winding) | — | |
| W36 | OEM-X-29 | MAXXECUSTREE-C1-A4 | 0.5 | no route | Idle speed control valve (open winding) | — | |
| W37 | OEM-X-41 | MAXXECUSTREE-C1-J3 | 0.5 | no route | Mass air flow (MAF) signal | — | |
| W38 | OEM-X-73 | MAXXECUSTREE-C1-G2 | 0.5 | no route | Throttle position (TPS) | — | |
| W39 | OEM-X-13 | MAXXECUSTREE-C1-J4 | 0.5 | no route | O2 sensor signal | — | |
| W40 | OEM-X-78 | MAXXECUSTREE-C1-J1 | 0.5 | no route | Engine coolant temperature (ECT) | — | |
| W41 | OEM-X-77 | MAXXECUSTREE-C1-J2 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W42 | OEM-X-42 | MAXXECUSTREE-C1-K3 | 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 (1)
| Severity | Code | Subject | Message |
|---|---|---|---|
| info | UNMAPPED | OEM | 7 optional OEM pins are not mapped: OEM-X-36 Evap purge solenoid; 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 2026-10-06. Review every wire against both manuals before building. Not wired: - OEM-X 26: Battery voltage (constant +12V): MaxxECU MaxxECU STREET has no battery-constant input; not needed - OEM-X 70: Knock sensor cylinders 1-3: no free knock input on MaxxECU MaxxECU STREET - OEM-X 69: Knock sensor cylinders 4-6: no free knock input on MaxxECU MaxxECU STREET - 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); MaxxECU MaxxECU STREET has no dedicated key-on input - OEM-X 36: Evap purge solenoid: no free low_side/ls_hs/injector/hbridge on MaxxECU MaxxECU STREET - OEM-X 7: VANOS intake camshaft solenoid: no free low_side/ls_hs/injector/hbridge on MaxxECU MaxxECU STREET - OEM-X 8: Check engine light (MIL): no free low_side/ls_hs/injector/hbridge on MaxxECU MaxxECU STREET - OEM-X 47: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on MaxxECU MaxxECU STREET
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | Link BMWLink E36X (G4X) plug-in install manual | https://linkecu.com/documentation/E36X.pdf | archive | 2026-10-05 | 010cda3acd08 |
| 4 | vendor_doc | MaxxECU GEN1 pinout (MINI / STREET / SPORT / V1 / RACE / PRO) | http://www.maxxecu.com/webhelp/wirings-maxxecu_pinout.html | archive | 2026-10-05 | 2e37b6814690 |
| 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/ | — | — | — |