BMW 3 Series E36 1990–2000 (M50/M52) → MaxxECU MaxxECU GEN2 TRACK (auto)
BMW 3 Series E36 1990–2000 (M50/M52) — MaxxECU — MaxxECU GEN2 TRACK
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 | 50 wires · 8 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 | MAXXECUGEN2T-MX1-25 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | SP-14V-1 | MAXXECUGEN2T-MX2-25 | 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 | MAXXECUGEN2T-MX1-9 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-GND-1 | MAXXECUGEN2T-MX2-9 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-GND-1 | MAXXECUGEN2T-MX3-9 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-X-28 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-X-40 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | OEM-X-43 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-X-44 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-X-71 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | SP-0V-1 | MAXXECUGEN2T-MX1-14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-X-59 | MAXXECUGEN2T-MX1-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-X-16 | MAXXECUGEN2T-MX1-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-X-17 | MAXXECUGEN2T-MX1-18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-X-70 | MAXXECUGEN2T-MX2-28 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-X-69 | MAXXECUGEN2T-MX2-31 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-X-50 | MAXXECUGEN2T-MX1-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-X-51 | MAXXECUGEN2T-MX1-2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-X-52 | MAXXECUGEN2T-MX1-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-X-23 | MAXXECUGEN2T-MX1-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-X-25 | MAXXECUGEN2T-MX2-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-X-24 | MAXXECUGEN2T-MX2-2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-X-33 | MAXXECUGEN2T-MX1-31 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-X-32 | MAXXECUGEN2T-MX1-32 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-X-31 | MAXXECUGEN2T-MX1-33 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-X-5 | MAXXECUGEN2T-MX1-34 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-X-3 | MAXXECUGEN2T-MX2-33 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-X-4 | MAXXECUGEN2T-MX2-34 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-X-45 | SP-SHD-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | SP-SHD-1 | MAXXECUGEN2T-MX1-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-X-56 | MAXXECUGEN2T-MX2-24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-X-1 | MAXXECUGEN2T-MX1-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-X-27 | MAXXECUGEN2T-MX1-6 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-X-38 | MAXXECUGEN2T-MX2-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-X-2 | MAXXECUGEN2T-MX1-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-X-29 | MAXXECUGEN2T-MX1-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W42 | OEM-X-36 | MAXXECUGEN2T-MX1-17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W43 | OEM-X-7 | MAXXECUGEN2T-MX2-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W44 | OEM-X-8 | MAXXECUGEN2T-MX3-29 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W45 | OEM-X-41 | MAXXECUGEN2T-MX1-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W46 | OEM-X-73 | MAXXECUGEN2T-MX1-27 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W47 | OEM-X-13 | MAXXECUGEN2T-MX1-28 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W48 | OEM-X-78 | MAXXECUGEN2T-MX1-29 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W49 | OEM-X-77 | MAXXECUGEN2T-MX1-30 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W50 | OEM-X-42 | MAXXECUGEN2T-MX1-23 | 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 | MAXXECUGEN2T-MX1-14 | MAXXECUGEN2T-MX1-12 | open (OL) | sensor ground must not touch 5 V sensor reference | |
| 2 | MAXXECUGEN2T-MX1-14 | MAXXECUGEN2T-MX1-25 | open (OL) | sensor ground must not touch +12 V supply | |
| 3 | MAXXECUGEN2T-MX1-25 | MAXXECUGEN2T-MX1-12 | open (OL) | +12 V supply must not touch 5 V sensor reference | |
| 4 | MAXXECUGEN2T-MX1-9 | MAXXECUGEN2T-MX1-12 | open (OL) | power ground must not touch 5 V sensor reference | |
| 5 | MAXXECUGEN2T-MX1-9 | MAXXECUGEN2T-MX1-25 | open (OL) | power ground must not touch +12 V supply |
Revisions
| Rev | Label | By | Date |
|---|---|---|---|
| No revisions yet. | |||
Schematic
Connectors
MAXXECUGEN2T-MX1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Ignition 1 | — | W22 | — | 0.5 | OEM-X-50 | — | — | — |
| 10 | Digital/VR 1 SIGNAL + | — | W18 | — | 0.5 | OEM-X-16 | — | — | — |
| 11 | Digital/VR 1 SIGNAL - | — | W35 | — | 0.5 | SP-SHD-1 | — | — | — |
| 12 | Digital/VR 1 POWER SUPPLY | — | W17 | — | 0.5 | OEM-X-59 | — | — | — |
| 13 | Digital/VR 1 SHIELD | — | — | — | — | — | — | — | — |
| 14 | SENSOR GND | — | W16 | — | 0.5 | SP-0V-1 | — | — | — |
| 15 | CAN L | — | — | — | — | — | — | — | — |
| 16 | CAN H | — | — | — | — | — | — | — | — |
| 17 | GP out 5 (GND) | — | W42 | — | 0.5 | OEM-X-36 | — | — | — |
| 18 | Digital/VR 2 SIGNAL + | — | W19 | — | 0.5 | OEM-X-17 | — | — | — |
| 19 | Digital/VR 2 SIGNAL - | — | — | — | — | — | — | — | — |
| 2 | Ignition 2 | — | W23 | — | 0.5 | OEM-X-51 | — | — | — |
| 20 | Digital/VR 2 POWER SUPPLY | — | — | — | — | — | — | — | — |
| 21 | Digital/VR 2 SHIELD | — | — | — | — | — | — | — | — |
| 22 | 5V power supply | — | — | — | — | — | — | — | — |
| 23 | Digital/VR 3 SIGNAL + | — | W50 | — | 0.5 | OEM-X-42 | — | — | — |
| 24 | Digital/VR 4 SIGNAL + | — | — | — | — | — | — | — | — |
| 25 | 12V supply 1 | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| 26 | AIN 1 | — | W45 | — | 0.5 | OEM-X-41 | — | — | — |
| 27 | AIN 2 | — | W46 | — | 0.5 | OEM-X-73 | — | — | — |
| 28 | AIN 3 | — | W47 | — | 0.5 | OEM-X-13 | — | — | — |
| 29 | AIN 4 | — | W48 | — | 0.5 | OEM-X-78 | — | — | — |
| 3 | Ignition 3 | — | W24 | — | 0.5 | OEM-X-52 | — | — | — |
| 30 | AIN 5 | — | W49 | — | 0.5 | OEM-X-77 | — | — | — |
| 31 | INJECTOR 1 | — | W28 | — | 0.5 | OEM-X-33 | — | — | — |
| 32 | INJECTOR 2 | — | W29 | — | 0.5 | OEM-X-32 | — | — | — |
| 33 | INJECTOR 3 | — | W30 | — | 0.5 | OEM-X-31 | — | — | — |
| 34 | INJECTOR 4 | — | W31 | — | 0.5 | OEM-X-5 | — | — | — |
| 4 | Ignition 4 | — | W25 | — | 0.5 | OEM-X-23 | — | — | — |
| 5 | GP out 1 (GND) | — | W37 | — | 0.5 | OEM-X-1 | — | — | — |
| 6 | GP out 2 (GND) | — | W38 | — | 0.5 | OEM-X-27 | — | — | — |
| 7 | GP out 3 (GND) | — | W40 | — | 0.5 | OEM-X-2 | — | — | — |
| 8 | GP out 4 (GND) | — | W41 | — | 0.5 | OEM-X-29 | — | — | — |
| 9 | Engine gnd | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
MAXXECUGEN2T-MX2
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Ignition 5 | — | W26 | — | 0.5 | OEM-X-25 | — | — | — |
| 10 | WBO2 Sensor 1 VS | — | — | — | — | — | — | — | — |
| 11 | WBO2 Sensor 1 COM/VREF | — | — | — | — | — | — | — | — |
| 12 | GP OUT 7 / WBO2 Sensor 1 H- | — | W39 | — | 0.5 | OEM-X-38 | — | — | — |
| 13 | AIN 9 | — | — | — | — | — | — | — | — |
| 14 | AIN 10 | — | — | — | — | — | — | — | — |
| 15 | AIN 11 | — | — | — | — | — | — | — | — |
| 16 | AIN 12 | — | — | — | — | — | — | — | — |
| 17 | AIN 13 | — | — | — | — | — | — | — | — |
| 18 | WBO2 sensor 1 RCAL | — | — | — | — | — | — | — | — |
| 19 | WBO2 sensor 1 IP | — | — | — | — | — | — | — | — |
| 2 | Ignition 6 | — | W27 | — | 0.5 | OEM-X-24 | — | — | — |
| 20 | 12V WBO2 sensor 1 H+ | — | — | — | — | — | — | — | — |
| 21 | WBO2 sensor 1 SHIELD | — | — | — | — | — | — | — | — |
| 22 | AIN 14 | — | — | — | — | — | — | — | — |
| 23 | AIN 15 | — | — | — | — | — | — | — | — |
| 24 | 12V supply 3 | — | W36 | — | 0.5 | OEM-X-56 | — | — | — |
| 25 | 12V supply 2 | — | W3 | — | 0.85 | SP-14V-1 | — | — | — |
| 26 | KNOCK1 SHIELD | — | — | — | — | — | — | — | — |
| 27 | KNOCK 1- | — | — | — | — | — | — | — | — |
| 28 | KNOCK 1+ | — | W20 | — | 0.5 | OEM-X-70 | — | — | — |
| 29 | KNOCK 2 SHIELD | — | — | — | — | — | — | — | — |
| 3 | GP out 6 (GND) | — | W43 | — | 0.5 | OEM-X-7 | — | — | — |
| 30 | KNOCK 2- | — | — | — | — | — | — | — | — |
| 31 | KNOCK 2+ | — | W21 | — | 0.5 | OEM-X-69 | — | — | — |
| 32 | AIN 16 | — | — | — | — | — | — | — | — |
| 33 | INJECTOR 5 | — | W32 | — | 0.5 | OEM-X-3 | — | — | — |
| 34 | INJECTOR 6 | — | W33 | — | 0.5 | OEM-X-4 | — | — | — |
| 4 | AIN 6 | — | — | — | — | — | — | — | — |
| 5 | AIN 7 | — | — | — | — | — | — | — | — |
| 6 | AIN 8 | — | — | — | — | — | — | — | — |
| 7 | GP out 13 (H-BRIDGE 1) | — | — | — | — | — | — | — | — |
| 8 | GP out 14 (H-BRIDGE 1) | — | — | — | — | — | — | — | — |
| 9 | Engine gnd | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
MAXXECUGEN2T-MX3
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | GP out 15 (H-BRIDGE 2) | — | — | — | — | — | — | — | — |
| 10 | WBO2 sensor 2 VS | — | — | — | — | — | — | — | — |
| 11 | WBO2 sensor 2 COM/VREF | — | — | — | — | — | — | — | — |
| 12 | GP Out 8 (GND) / WBO2 Sensor 2 H- | — | — | — | — | — | — | — | — |
| 14 | GP OUT 9 (12V) | — | — | — | — | — | — | — | — |
| 15 | GP OUT 10 (12V) | — | — | — | — | — | — | — | — |
| 16 | GP OUT 11 (12V) | — | — | — | — | — | — | — | — |
| 17 | GP OUT 12 (12V) | — | — | — | — | — | — | — | — |
| 18 | WBO2 sensor 2 RCAL | — | — | — | — | — | — | — | — |
| 19 | WBO2 sensor 2 IP | — | — | — | — | — | — | — | — |
| 2 | GP out 16 (H-BRIDGE 2) | — | — | — | — | — | — | — | — |
| 20 | 12V WBO2 sensor 2 (H+) | — | — | — | — | — | — | — | — |
| 21 | Digital/VR 5 SIGNAL + | — | — | — | — | — | — | — | — |
| 22 | Digital/VR 5 SIGNAL - | — | — | — | — | — | — | — | — |
| 23 | Digital/VR 5 SHIELD | — | — | — | — | — | — | — | — |
| 24 | CAN 2 L | — | — | — | — | — | — | — | — |
| 25 | CAN 2 H | — | — | — | — | — | — | — | — |
| 26 | Digital/VR 6 SIGNAL + | — | — | — | — | — | — | — | — |
| 27 | Digital/VR 6 SIGNAL - | — | — | — | — | — | — | — | — |
| 28 | Digital/VR 6 SHIELD | — | — | — | — | — | — | — | — |
| 29 | INJECTOR 7 | — | W44 | — | 0.5 | OEM-X-8 | — | — | — |
| 3 | Ignition 7 | — | — | — | — | — | — | — | — |
| 30 | INJECTOR 8 | — | — | — | — | — | — | — | — |
| 4 | Ignition 8 | — | — | — | — | — | — | — | — |
| 9 | Engine gnd | — | W10 | — | 0.85 | SP-GND-1 | — | — | — |
OEM-X
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Fuel pump relay control | — | W37 | — | 0.5 | MAXXECUGEN2T-MX1-5 | — | — | — |
| 13 | O2 sensor signal | — | W47 | — | 0.5 | MAXXECUGEN2T-MX1-28 | — | — | — |
| 15 | Ground | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| 16 | Crank position sensor (+) | — | W18 | — | 0.5 | MAXXECUGEN2T-MX1-10 | — | — | — |
| 17 | Camshaft position sensor (Hall) | — | W19 | — | 0.5 | MAXXECUGEN2T-MX1-18 | — | — | — |
| 2 | Idle speed control valve (close winding) | — | W40 | — | 0.5 | MAXXECUGEN2T-MX1-7 | — | — | — |
| 23 | Ignition coil cylinder 4 | — | W25 | — | 0.5 | MAXXECUGEN2T-MX1-4 | — | — | — |
| 24 | Ignition coil cylinder 6 | — | W27 | — | 0.5 | MAXXECUGEN2T-MX2-2 | — | — | — |
| 25 | Ignition coil cylinder 5 | — | W26 | — | 0.5 | MAXXECUGEN2T-MX2-1 | — | — | — |
| 26 | Battery voltage (constant +12V) | — | — | — | — | — | — | — | — |
| 27 | Main relay control | — | W38 | — | 0.5 | MAXXECUGEN2T-MX1-6 | — | — | — |
| 28 | Ground (electronics + sensor shielding) | — | W11 | — | 0.5 | SP-0V-1 | — | — | — |
| 29 | Idle speed control valve (open winding) | — | W41 | — | 0.5 | MAXXECUGEN2T-MX1-8 | — | — | — |
| 3 | Injector cylinder 5 | — | W32 | — | 0.5 | MAXXECUGEN2T-MX2-33 | — | — | — |
| 31 | Injector cylinder 3 | — | W30 | — | 0.5 | MAXXECUGEN2T-MX1-33 | — | — | — |
| 32 | Injector cylinder 2 | — | W29 | — | 0.5 | MAXXECUGEN2T-MX1-32 | — | — | — |
| 33 | Injector cylinder 1 | — | W28 | — | 0.5 | MAXXECUGEN2T-MX1-31 | — | — | — |
| 34 | Ground (output stages) | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| 36 | Evap purge solenoid | — | W42 | — | 0.5 | MAXXECUGEN2T-MX1-17 | — | — | — |
| 38 | O2 sensor heater relay control | — | W39 | — | 0.5 | MAXXECUGEN2T-MX2-12 | — | — | — |
| 4 | Injector cylinder 6 | — | W33 | — | 0.5 | MAXXECUGEN2T-MX2-34 | — | — | — |
| 40 | O2 sensor signal ground | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| 41 | Mass air flow (MAF) signal | — | W45 | — | 0.5 | MAXXECUGEN2T-MX1-26 | — | — | — |
| 42 | Vehicle speed signal | — | W50 | — | 0.5 | MAXXECUGEN2T-MX1-23 | — | — | — |
| 43 | Crank position sensor (-) | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 44 | Sensor ground (IAT/ECT/TPS) | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| 45 | Shield ground | — | W34 | — | 0.5 | SP-SHD-1 | — | — | — |
| 47 | Tachometer output | — | — | — | — | — | — | — | — |
| 5 | Injector cylinder 4 | — | W31 | — | 0.5 | MAXXECUGEN2T-MX1-34 | — | — | — |
| 50 | Ignition coil cylinder 1 | — | W22 | — | 0.5 | MAXXECUGEN2T-MX1-1 | — | — | — |
| 51 | Ignition coil cylinder 2 | — | W23 | — | 0.5 | MAXXECUGEN2T-MX1-2 | — | — | — |
| 52 | Ignition coil cylinder 3 | — | W24 | — | 0.5 | MAXXECUGEN2T-MX1-3 | — | — | — |
| 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) | — | W36 | — | 0.5 | MAXXECUGEN2T-MX2-24 | — | — | — |
| 59 | +5V sensor supply | — | W17 | — | 0.5 | MAXXECUGEN2T-MX1-12 | — | — | — |
| 6 | Ground (injector output stages) | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| 69 | Knock sensor cylinders 4-6 | — | W21 | — | 0.5 | MAXXECUGEN2T-MX2-31 | — | — | — |
| 7 | VANOS intake camshaft solenoid | — | W43 | — | 0.5 | MAXXECUGEN2T-MX2-3 | — | — | — |
| 70 | Knock sensor cylinders 1-3 | — | W20 | — | 0.5 | MAXXECUGEN2T-MX2-28 | — | — | — |
| 71 | Knock sensor ground/shield | — | W15 | — | 0.5 | SP-0V-1 | — | — | — |
| 73 | Throttle position (TPS) | — | W46 | — | 0.5 | MAXXECUGEN2T-MX1-27 | — | — | — |
| 77 | Intake air temperature (IAT) | — | W49 | — | 0.5 | MAXXECUGEN2T-MX1-30 | — | — | — |
| 78 | Engine coolant temperature (ECT) | — | W48 | — | 0.5 | MAXXECUGEN2T-MX1-29 | — | — | — |
| 8 | Check engine light (MIL) | — | W44 | — | 0.5 | MAXXECUGEN2T-MX3-29 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W11 | — | 0.5 | OEM-X-28 | — | — | — |
| 1 | — | — | W12 | — | 0.5 | OEM-X-40 | — | — | — |
| 1 | — | — | W13 | — | 0.5 | OEM-X-43 | — | — | — |
| 1 | — | — | W14 | — | 0.5 | OEM-X-44 | — | — | — |
| 1 | — | — | W15 | — | 0.5 | OEM-X-71 | — | — | — |
| 1 | — | — | W16 | — | 0.5 | MAXXECUGEN2T-MX1-14 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-X-54 | — | — | — |
| 1 | — | — | W2 | — | 0.85 | MAXXECUGEN2T-MX1-25 | — | — | — |
| 1 | — | — | W3 | — | 0.85 | MAXXECUGEN2T-MX2-25 | — | — | — |
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 | MAXXECUGEN2T-MX1-9 | — | — | — |
| 1 | — | — | W9 | — | 0.85 | MAXXECUGEN2T-MX2-9 | — | — | — |
| 1 | — | — | W10 | — | 0.85 | MAXXECUGEN2T-MX3-9 | — | — | — |
SP-SHD
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W34 | — | 0.5 | OEM-X-45 | — | — | — |
| 1 | — | — | W35 | — | 0.5 | MAXXECUGEN2T-MX1-11 | — | — | — |
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 | MAXXECUGEN2T-MX1-5 | GP out 1 (GND) | low_side_out | corroborated | |
| OEM-X-13 | O2 sensor signal | lambda_nb_in | MAXXECUGEN2T-MX1-28 | AIN 3 | analog_in | corroborated | |
| OEM-X-15 | Ground | ground | MAXXECUGEN2T-MX1-9 + MAXXECUGEN2T-MX2-9 + MAXXECUGEN2T-MX3-9 | Engine gnd + Engine gnd + Engine gnd | ground | corroborated | |
| OEM-X-16 | Crank position sensor (+) | trigger_in | MAXXECUGEN2T-MX1-10 | Digital/VR 1 SIGNAL + | trigger_in | corroborated | |
| OEM-X-17 | Camshaft position sensor (Hall) | trigger_in | MAXXECUGEN2T-MX1-18 | Digital/VR 2 SIGNAL + | trigger_in | corroborated | |
| OEM-X-2 | Idle speed control valve (close winding) | low_side_out | MAXXECUGEN2T-MX1-7 | GP out 3 (GND) | low_side_out | corroborated | |
| OEM-X-23 | Ignition coil cylinder 4 | ignition_out | MAXXECUGEN2T-MX1-4 | Ignition 4 | ignition_out | corroborated | |
| OEM-X-24 | Ignition coil cylinder 6 | ignition_out | MAXXECUGEN2T-MX2-2 | Ignition 6 | ignition_out | corroborated | |
| OEM-X-25 | Ignition coil cylinder 5 | ignition_out | MAXXECUGEN2T-MX2-1 | Ignition 5 | ignition_out | corroborated | |
| OEM-X-26 | Battery voltage (constant +12V) | power_in | — | — | — | corroborated | |
| OEM-X-27 | Main relay control | low_side_out | MAXXECUGEN2T-MX1-6 | GP out 2 (GND) | low_side_out | corroborated | |
| OEM-X-28 | Ground (electronics + sensor shielding) | sensor_ground | MAXXECUGEN2T-MX1-14 | SENSOR GND | sensor_ground | corroborated | |
| OEM-X-29 | Idle speed control valve (open winding) | low_side_out | MAXXECUGEN2T-MX1-8 | GP out 4 (GND) | low_side_out | corroborated | |
| OEM-X-3 | Injector cylinder 5 | injector_out | MAXXECUGEN2T-MX2-33 | INJECTOR 5 | injector_out | corroborated | |
| OEM-X-31 | Injector cylinder 3 | injector_out | MAXXECUGEN2T-MX1-33 | INJECTOR 3 | injector_out | corroborated | |
| OEM-X-32 | Injector cylinder 2 | injector_out | MAXXECUGEN2T-MX1-32 | INJECTOR 2 | injector_out | corroborated | |
| OEM-X-33 | Injector cylinder 1 | injector_out | MAXXECUGEN2T-MX1-31 | INJECTOR 1 | injector_out | corroborated | |
| OEM-X-34 | Ground (output stages) | ground | MAXXECUGEN2T-MX1-9 + MAXXECUGEN2T-MX2-9 + MAXXECUGEN2T-MX3-9 | Engine gnd + Engine gnd + Engine gnd | ground | corroborated | |
| OEM-X-36 | Evap purge solenoid | low_side_out | MAXXECUGEN2T-MX1-17 | GP out 5 (GND) | low_side_out | corroborated | |
| OEM-X-38 | O2 sensor heater relay control | low_side_out | MAXXECUGEN2T-MX2-12 | GP OUT 7 / WBO2 Sensor 1 H- | low_side_out | corroborated | |
| OEM-X-4 | Injector cylinder 6 | injector_out | MAXXECUGEN2T-MX2-34 | INJECTOR 6 | injector_out | corroborated | |
| OEM-X-40 | O2 sensor signal ground | sensor_ground | MAXXECUGEN2T-MX1-14 | SENSOR GND | sensor_ground | corroborated | |
| OEM-X-41 | Mass air flow (MAF) signal | analog_in | MAXXECUGEN2T-MX1-26 | AIN 1 | analog_in | corroborated | |
| OEM-X-42 | Vehicle speed signal | digital_in | MAXXECUGEN2T-MX1-23 | Digital/VR 3 SIGNAL + | digital_in | corroborated | |
| OEM-X-43 | Crank position sensor (-) | sensor_ground | MAXXECUGEN2T-MX1-14 | SENSOR GND | sensor_ground | corroborated | |
| OEM-X-44 | Sensor ground (IAT/ECT/TPS) | sensor_ground | MAXXECUGEN2T-MX1-14 | SENSOR GND | sensor_ground | corroborated | |
| OEM-X-45 | Shield ground | shield | MAXXECUGEN2T-MX1-11 | Digital/VR 1 SIGNAL - | shield | corroborated | |
| OEM-X-47 | Tachometer output | tacho_out | — | — | — | corroborated | |
| OEM-X-5 | Injector cylinder 4 | injector_out | MAXXECUGEN2T-MX1-34 | INJECTOR 4 | injector_out | corroborated | |
| OEM-X-50 | Ignition coil cylinder 1 | ignition_out | MAXXECUGEN2T-MX1-1 | Ignition 1 | ignition_out | corroborated | |
| OEM-X-51 | Ignition coil cylinder 2 | ignition_out | MAXXECUGEN2T-MX1-2 | Ignition 2 | ignition_out | corroborated | |
| OEM-X-52 | Ignition coil cylinder 3 | ignition_out | MAXXECUGEN2T-MX1-3 | Ignition 3 | ignition_out | corroborated | |
| OEM-X-54 | ECU power (+14V from main relay) | power_in | MAXXECUGEN2T-MX1-25 + MAXXECUGEN2T-MX2-25 | 12V supply 1 + 12V supply 2 | power_in | corroborated | |
| OEM-X-55 | Ground (ignition) | ground | MAXXECUGEN2T-MX1-9 + MAXXECUGEN2T-MX2-9 + MAXXECUGEN2T-MX3-9 | Engine gnd + Engine gnd + Engine gnd | ground | corroborated | |
| OEM-X-56 | Ignition switch (terminal 15) | digital_in | MAXXECUGEN2T-MX2-24 | 12V supply 3 | digital_in | corroborated | |
| OEM-X-59 | +5V sensor supply | vref | MAXXECUGEN2T-MX1-12 | Digital/VR 1 POWER SUPPLY | vref | corroborated | |
| OEM-X-6 | Ground (injector output stages) | ground | MAXXECUGEN2T-MX1-9 + MAXXECUGEN2T-MX2-9 + MAXXECUGEN2T-MX3-9 | Engine gnd + Engine gnd + Engine gnd | ground | corroborated | |
| OEM-X-69 | Knock sensor cylinders 4-6 | knock_in | MAXXECUGEN2T-MX2-31 | KNOCK 2+ | knock_in | corroborated | |
| OEM-X-7 | VANOS intake camshaft solenoid | low_side_out | MAXXECUGEN2T-MX2-3 | GP out 6 (GND) | low_side_out | corroborated | |
| OEM-X-70 | Knock sensor cylinders 1-3 | knock_in | MAXXECUGEN2T-MX2-28 | KNOCK 1+ | knock_in | corroborated | |
| OEM-X-71 | Knock sensor ground/shield | sensor_ground | MAXXECUGEN2T-MX1-14 | SENSOR GND | sensor_ground | corroborated | |
| OEM-X-73 | Throttle position (TPS) | analog_in | MAXXECUGEN2T-MX1-27 | AIN 2 | analog_in | corroborated | |
| OEM-X-77 | Intake air temperature (IAT) | temp_in | MAXXECUGEN2T-MX1-30 | AIN 5 | analog_in | corroborated | |
| OEM-X-78 | Engine coolant temperature (ECT) | temp_in | MAXXECUGEN2T-MX1-29 | AIN 4 | analog_in | corroborated | |
| OEM-X-8 | Check engine light (MIL) | low_side_out | MAXXECUGEN2T-MX3-29 | INJECTOR 7 | injector_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 | MAXXECUGEN2T-MX1-25 | 0.85 | no route | 12V supply 1 | — | |
| W3 | SP-14V-1 | MAXXECUGEN2T-MX2-25 | 0.85 | no route | 12V supply 2 | — | |
| 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 | MAXXECUGEN2T-MX1-9 | 0.85 | no route | Engine gnd | — | |
| W9 | SP-GND-1 | MAXXECUGEN2T-MX2-9 | 0.85 | no route | Engine gnd | — | |
| W10 | SP-GND-1 | MAXXECUGEN2T-MX3-9 | 0.85 | no route | Engine gnd | — | |
| W11 | OEM-X-28 | SP-0V-1 | 0.5 | no route | Ground (electronics + sensor shielding) | — | |
| W12 | OEM-X-40 | SP-0V-1 | 0.5 | no route | O2 sensor signal ground | — | |
| W13 | OEM-X-43 | SP-0V-1 | 0.5 | no route | Crank position sensor (-) | — | |
| W14 | OEM-X-44 | SP-0V-1 | 0.5 | no route | Sensor ground (IAT/ECT/TPS) | — | |
| W15 | OEM-X-71 | SP-0V-1 | 0.5 | no route | Knock sensor ground/shield | — | |
| W16 | SP-0V-1 | MAXXECUGEN2T-MX1-14 | 0.5 | no route | SENSOR GND | — | |
| W17 | OEM-X-59 | MAXXECUGEN2T-MX1-12 | 0.5 | no route | +5V sensor supply | — | |
| W18 | OEM-X-16 | MAXXECUGEN2T-MX1-10 | 0.5 | no route | Crank position sensor (+) | — | |
| W19 | OEM-X-17 | MAXXECUGEN2T-MX1-18 | 0.5 | no route | Camshaft position sensor (Hall) | — | |
| W20 | OEM-X-70 | MAXXECUGEN2T-MX2-28 | 0.5 | no route | Knock sensor cylinders 1-3 | — | |
| W21 | OEM-X-69 | MAXXECUGEN2T-MX2-31 | 0.5 | no route | Knock sensor cylinders 4-6 | — | |
| W22 | OEM-X-50 | MAXXECUGEN2T-MX1-1 | 0.5 | no route | Ignition coil cylinder 1 | — | |
| W23 | OEM-X-51 | MAXXECUGEN2T-MX1-2 | 0.5 | no route | Ignition coil cylinder 2 | — | |
| W24 | OEM-X-52 | MAXXECUGEN2T-MX1-3 | 0.5 | no route | Ignition coil cylinder 3 | — | |
| W25 | OEM-X-23 | MAXXECUGEN2T-MX1-4 | 0.5 | no route | Ignition coil cylinder 4 | — | |
| W26 | OEM-X-25 | MAXXECUGEN2T-MX2-1 | 0.5 | no route | Ignition coil cylinder 5 | — | |
| W27 | OEM-X-24 | MAXXECUGEN2T-MX2-2 | 0.5 | no route | Ignition coil cylinder 6 | — | |
| W28 | OEM-X-33 | MAXXECUGEN2T-MX1-31 | 0.5 | no route | Injector cylinder 1 | — | |
| W29 | OEM-X-32 | MAXXECUGEN2T-MX1-32 | 0.5 | no route | Injector cylinder 2 | — | |
| W30 | OEM-X-31 | MAXXECUGEN2T-MX1-33 | 0.5 | no route | Injector cylinder 3 | — | |
| W31 | OEM-X-5 | MAXXECUGEN2T-MX1-34 | 0.5 | no route | Injector cylinder 4 | — | |
| W32 | OEM-X-3 | MAXXECUGEN2T-MX2-33 | 0.5 | no route | Injector cylinder 5 | — | |
| W33 | OEM-X-4 | MAXXECUGEN2T-MX2-34 | 0.5 | no route | Injector cylinder 6 | — | |
| W34 | OEM-X-45 | SP-SHD-1 | 0.5 | no route | Shield ground | — | |
| W35 | SP-SHD-1 | MAXXECUGEN2T-MX1-11 | 0.5 | no route | Digital/VR 1 SIGNAL - | — | |
| W36 | OEM-X-56 | MAXXECUGEN2T-MX2-24 | 0.5 | no route | Ignition switch (terminal 15) | — | |
| W37 | OEM-X-1 | MAXXECUGEN2T-MX1-5 | 0.5 | no route | Fuel pump relay control | — | |
| W38 | OEM-X-27 | MAXXECUGEN2T-MX1-6 | 0.5 | no route | Main relay control | — | |
| W39 | OEM-X-38 | MAXXECUGEN2T-MX2-12 | 0.5 | no route | O2 sensor heater relay control | — | |
| W40 | OEM-X-2 | MAXXECUGEN2T-MX1-7 | 0.5 | no route | Idle speed control valve (close winding) | — | |
| W41 | OEM-X-29 | MAXXECUGEN2T-MX1-8 | 0.5 | no route | Idle speed control valve (open winding) | — | |
| W42 | OEM-X-36 | MAXXECUGEN2T-MX1-17 | 0.5 | no route | Evap purge solenoid | — | |
| W43 | OEM-X-7 | MAXXECUGEN2T-MX2-3 | 0.5 | no route | VANOS intake camshaft solenoid | — | |
| W44 | OEM-X-8 | MAXXECUGEN2T-MX3-29 | 0.5 | no route | Check engine light (MIL) | — | |
| W45 | OEM-X-41 | MAXXECUGEN2T-MX1-26 | 0.5 | no route | Mass air flow (MAF) signal | — | |
| W46 | OEM-X-73 | MAXXECUGEN2T-MX1-27 | 0.5 | no route | Throttle position (TPS) | — | |
| W47 | OEM-X-13 | MAXXECUGEN2T-MX1-28 | 0.5 | no route | O2 sensor signal | — | |
| W48 | OEM-X-78 | MAXXECUGEN2T-MX1-29 | 0.5 | no route | Engine coolant temperature (ECT) | — | |
| W49 | OEM-X-77 | MAXXECUGEN2T-MX1-30 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W50 | OEM-X-42 | MAXXECUGEN2T-MX1-23 | 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 (4)
| Severity | Code | Subject | Message |
|---|---|---|---|
| info | NET_FAMILY | OEM-X-77 ↔ MAXXECUGEN2T-MX1-30 | OEM-X-77 "Intake air temperature (IAT)" [temp_in] is wired to MAXXECUGEN2T-MX1-30 "AIN 5" [analog_in]. Thermistor on a plain analog input needs a pull-up; check the channel can enable one. |
| info | NET_FAMILY | OEM-X-78 ↔ MAXXECUGEN2T-MX1-29 | OEM-X-78 "Engine coolant temperature (ECT)" [temp_in] is wired to MAXXECUGEN2T-MX1-29 "AIN 4" [analog_in]. Thermistor on a plain analog input needs a pull-up; check the channel can enable one. |
| info | NET_FAMILY | OEM-X-8 ↔ MAXXECUGEN2T-MX3-29 | OEM-X-8 "Check engine light (MIL)" [low_side_out] is wired to MAXXECUGEN2T-MX3-29 "INJECTOR 7" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency. |
| info | UNMAPPED | OEM | 1 optional OEM pins are not mapped: OEM-X-47 Tachometer output |
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 GEN2 TRACK has no battery-constant input; not needed - OEM-X 47: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on MaxxECU MaxxECU GEN2 TRACK
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 GEN2 pinout (RACE MX1–MX4 / TRACK MX1–MX3) | http://www.maxxecu.com/webhelp/wirings-maxxecu_gen2_pinout.html | archive | 2026-10-05 | f689b8b6b08f |
| 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/ | — | — | — |