VW Corrado VR6 12v (AAA) Motronic M2.9 OBD1 → MaxxECU MaxxECU STREET REV9+ (auto)
VW Corrado VR6 12v (AAA) Motronic M2.9 OBD1 — MaxxECU — MaxxECU STREET
⚠ 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 | 2: read the Findings page before cutting any wire |
| Size of the job | 38 wires · 5 connectors · 0 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-A-23 | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | SP-14V-1 | MAXXECUSTREE-C1-M4 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-A-1 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | OEM-A-10 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | OEM-A-55 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-A-56 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-A-7 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | SP-GND-1 | MAXXECUSTREE-C1-L4 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | OEM-A-16 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | OEM-A-33 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-A-67 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | SP-0V-1 | MAXXECUSTREE-C1-H1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | SP-0V-1 | MAXXECUSTREE-C1-H2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-A-41 | MAXXECUSTREE-C1-G1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-A-68 | MAXXECUSTREE-C1-H3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | OEM-A-44 | MAXXECUSTREE-C1-H4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-A-8 | MAXXECUSTREE-C1-A2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-A-60 | MAXXECUSTREE-C1-A3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-A-52 | MAXXECUSTREE-C1-B2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-A-24 | MAXXECUSTREE-C1-K1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-A-3 | MAXXECUSTREE-C1-K2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-A-26 | MAXXECUSTREE-C1-M1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-A-4 | MAXXECUSTREE-C1-M2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-A-25 | MAXXECUSTREE-C1-M3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-A-2 | MAXXECUSTREE-C1-L3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-A-17 | MAXXECUSTREE-C1-J3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-A-40 | MAXXECUSTREE-C1-G2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-A-14 | MAXXECUSTREE-C1-F1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-A-49 | MAXXECUSTREE-C1-B4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-A-6 | MAXXECUSTREE-C1-C4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-A-9 | MAXXECUSTREE-C1-D4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-A-27 | MAXXECUSTREE-C1-A4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-A-31 | MAXXECUSTREE-C1-D1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-A-20 | MAXXECUSTREE-C1-J4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-A-15 | MAXXECUSTREE-C1-J1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-A-36 | MAXXECUSTREE-C1-F2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-A-65 | MAXXECUSTREE-C1-K3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-A-37 | MAXXECUSTREE-C1-K4 | 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 |
If any reading doesn't match, stop and get help before powering up.
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 | — | W17 | — | 0.5 | OEM-A-8 | — | — | — |
| A3 | IGN 2 | — | W18 | — | 0.5 | OEM-A-60 | — | — | — |
| A4 | GPO 8/TACHO | — | W32 | — | 0.5 | OEM-A-27 | — | — | — |
| B2 | IGN 3 | — | W19 | — | 0.5 | OEM-A-52 | — | — | — |
| B3 | IGN 4 | — | — | — | — | — | — | — | — |
| B4 | GPO 1 | — | W29 | — | 0.5 | OEM-A-49 | — | — | — |
| C2 | IGN 5 | — | — | — | — | — | — | — | — |
| C3 | IGN 6 | — | — | — | — | — | — | — | — |
| C4 | GPO 2 | — | W30 | — | 0.5 | OEM-A-6 | — | — | — |
| D1 | WBO2 Heater- | — | W33 | — | 0.5 | OEM-A-31 | — | — | — |
| D4 | GPO 3 | — | W31 | — | 0.5 | OEM-A-9 | — | — | — |
| E1 | CAN H | — | — | — | — | — | — | — | — |
| E2 | CAN L | — | — | — | — | — | — | — | — |
| E3 | GND Shield | — | — | — | — | — | — | — | — |
| F1 | CLT | — | W28 | — | 0.5 | OEM-A-14 | — | — | — |
| F2 | IAT | — | W36 | — | 0.5 | OEM-A-36 | — | — | — |
| F3 | WBO2 VREF | — | — | — | — | — | — | — | — |
| F4 | WBO2 VS | — | — | — | — | — | — | — | — |
| G1 | +5V sensor supply | — | W14 | — | 0.5 | OEM-A-41 | — | — | — |
| G2 | TPS/AIN | — | W27 | — | 0.5 | OEM-A-40 | — | — | — |
| G3 | WBO2 IP | — | — | — | — | — | — | — | — |
| G4 | WBO2 RCAL | — | — | — | — | — | — | — | — |
| H1 | Sensor GND | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| H2 | Trigger GND | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| H3 | TRIGGER | — | W15 | — | 0.5 | OEM-A-68 | — | — | — |
| H4 | HOME | — | W16 | — | 0.5 | OEM-A-44 | — | — | — |
| J1 | AIN 1 (temperature) | — | W35 | — | 0.5 | OEM-A-15 | — | — | — |
| J2 | AIN 2 (Temperature) | — | — | — | — | — | — | — | — |
| J3 | AIN 3 (0-5V) | — | W26 | — | 0.5 | OEM-A-17 | — | — | — |
| J4 | AIN 4 (0-5V) | — | W34 | — | 0.5 | OEM-A-20 | — | — | — |
| K1 | INJ 1 | — | W20 | — | 0.5 | OEM-A-24 | — | — | — |
| K2 | INJ 2 | — | W21 | — | 0.5 | OEM-A-3 | — | — | — |
| K3 | DIN 1 | — | W37 | — | 0.5 | OEM-A-65 | — | — | — |
| K4 | DIN 2 | — | W38 | — | 0.5 | OEM-A-37 | — | — | — |
| L3 | INJ 6 | — | W25 | — | 0.5 | OEM-A-2 | — | — | — |
| L4 | Engine GND | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| M1 | INJ 3 | — | W22 | — | 0.5 | OEM-A-26 | — | — | — |
| M2 | INJ 4 | — | W23 | — | 0.5 | OEM-A-4 | — | — | — |
| M3 | INJ 5 | — | W24 | — | 0.5 | OEM-A-25 | — | — | — |
| M4 | +12V ECU power supply | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
OEM-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Ground (E-1) | — | W3 | — | 0.85 | SP-GND-1 | — | — | — |
| 10 | Ground (OBD1 EGR enable) | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| 14 | Coolant temperature (CLT) | — | W28 | — | 0.5 | MAXXECUSTREE-C1-F1 | — | — | — |
| 15 | EGR temperature sensor | — | W35 | — | 0.5 | MAXXECUSTREE-C1-J1 | — | — | — |
| 16 | MAF ground | — | W9 | — | 0.5 | SP-0V-1 | — | — | — |
| 17 | MAF signal | — | W26 | — | 0.5 | MAXXECUSTREE-C1-J3 | — | — | — |
| 2 | Injector 6 (cyl 6) | — | W25 | — | 0.5 | MAXXECUSTREE-C1-L3 | — | — | — |
| 20 | O2 sensor 1 (primary) | — | W34 | — | 0.5 | MAXXECUSTREE-C1-J4 | — | — | — |
| 21 | Diagnostic L-line | — | — | — | — | — | — | — | — |
| 22 | Tachometer output | — | — | — | — | — | — | — | — |
| 23 | ECU main power (from engine-electronics relay) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| 24 | Injector 1 (cyl 1) | — | W20 | — | 0.5 | MAXXECUSTREE-C1-K1 | — | — | — |
| 25 | Injector 5 (cyl 5) | — | W24 | — | 0.5 | MAXXECUSTREE-C1-M3 | — | — | — |
| 26 | Injector 3 (cyl 3) | — | W22 | — | 0.5 | MAXXECUSTREE-C1-M1 | — | — | — |
| 27 | Idle air control valve | — | W32 | — | 0.5 | MAXXECUSTREE-C1-A4 | — | — | — |
| 3 | Injector 2 (cyl 2) | — | W21 | — | 0.5 | MAXXECUSTREE-C1-K2 | — | — | — |
| 31 | EVAP canister purge valve | — | W33 | — | 0.5 | MAXXECUSTREE-C1-D1 | — | — | — |
| 33 | Sensor ground bus | — | W10 | — | 0.5 | SP-0V-1 | — | — | — |
| 34 | Knock sensor 1 | — | — | — | — | — | — | — | — |
| 36 | Intake air temperature (IAT) | — | W36 | — | 0.5 | MAXXECUSTREE-C1-F2 | — | — | — |
| 37 | A/C compressor switch | — | W38 | — | 0.5 | MAXXECUSTREE-C1-K4 | — | — | — |
| 38 | Ignition switch (run/start) | — | — | — | — | — | — | — | — |
| 39 | A/C switch (cabin) | — | — | — | — | — | — | — | — |
| 4 | Injector 4 (cyl 4) | — | W23 | — | 0.5 | MAXXECUSTREE-C1-M2 | — | — | — |
| 40 | Throttle position sensor 1 | — | W27 | — | 0.5 | MAXXECUSTREE-C1-G2 | — | — | — |
| 41 | TPS power (+5V) | — | W14 | — | 0.5 | MAXXECUSTREE-C1-G1 | — | — | — |
| 43 | Diagnostic K-line | — | — | — | — | — | — | — | — |
| 44 | Camshaft position sensor (G40) | — | W16 | — | 0.5 | MAXXECUSTREE-C1-H4 | — | — | — |
| 49 | Secondary air injection relay control | — | W29 | — | 0.5 | MAXXECUSTREE-C1-B4 | — | — | — |
| 5 | Check engine light (MIL) | — | — | — | — | — | — | — | — |
| 51 | MFA fuel-consumption signal | — | — | — | — | — | — | — | — |
| 52 | Ignition coil 4 (coil pack pin 4) | — | W19 | — | 0.5 | MAXXECUSTREE-C1-B2 | — | — | — |
| 53 | Idle air control valve (2nd) | — | — | — | — | — | — | — | — |
| 54 | Battery constant (+12V) | — | — | — | — | — | — | — | — |
| 55 | Ground (E-3) | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| 56 | Ground (E-4) | — | W6 | — | 0.85 | SP-GND-1 | — | — | — |
| 59 | Mass airflow sensor (5th terminal) | — | — | — | — | — | — | — | — |
| 6 | Fuel pump relay control | — | W30 | — | 0.5 | MAXXECUSTREE-C1-C4 | — | — | — |
| 60 | Ignition coil 3 (coil pack pin 3) | — | W18 | — | 0.5 | MAXXECUSTREE-C1-A3 | — | — | — |
| 65 | Vehicle speed sensor (VSS) | — | W37 | — | 0.5 | MAXXECUSTREE-C1-K3 | — | — | — |
| 67 | Crank sensor return (VR-) | — | W11 | — | 0.5 | SP-0V-1 | — | — | — |
| 68 | Crank position sensor (G28, VR+) | — | W15 | — | 0.5 | MAXXECUSTREE-C1-H3 | — | — | — |
| 7 | Ground (E-2) | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| 8 | Ignition coil 2 (coil pack pin 2) | — | W17 | — | 0.5 | MAXXECUSTREE-C1-A2 | — | — | — |
| 9 | Engine electronics relay control | — | W31 | — | 0.5 | MAXXECUSTREE-C1-D4 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W9 | — | 0.5 | OEM-A-16 | — | — | — |
| 1 | — | — | W10 | — | 0.5 | OEM-A-33 | — | — | — |
| 1 | — | — | W11 | — | 0.5 | OEM-A-67 | — | — | — |
| 1 | — | — | W12 | — | 0.5 | MAXXECUSTREE-C1-H1 | — | — | — |
| 1 | — | — | W13 | — | 0.5 | MAXXECUSTREE-C1-H2 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-A-23 | — | — | — |
| 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-A-1 | — | — | — |
| 1 | — | — | W4 | — | 0.85 | OEM-A-10 | — | — | — |
| 1 | — | — | W5 | — | 0.85 | OEM-A-55 | — | — | — |
| 1 | — | — | W6 | — | 0.85 | OEM-A-56 | — | — | — |
| 1 | — | — | W7 | — | 0.85 | OEM-A-7 | — | — | — |
| 1 | — | — | W8 | — | 0.85 | MAXXECUSTREE-C1-L4 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-A-1 | Ground (E-1) | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | single_source | |
| OEM-A-10 | Ground (OBD1 EGR enable) | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | single_source | |
| OEM-A-14 | Coolant temperature (CLT) | temp_in | MAXXECUSTREE-C1-F1 | CLT | temp_in | single_source | |
| OEM-A-15 | EGR temperature sensor | temp_in | MAXXECUSTREE-C1-J1 | AIN 1 (temperature) | temp_in | single_source | |
| OEM-A-16 | MAF ground | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | single_source | |
| OEM-A-17 | MAF signal | analog_in | MAXXECUSTREE-C1-J3 | AIN 3 (0-5V) | analog_in | single_source | |
| OEM-A-2 | Injector 6 (cyl 6) | injector_out | MAXXECUSTREE-C1-L3 | INJ 6 | injector_out | single_source | |
| OEM-A-20 | O2 sensor 1 (primary) | lambda_nb_in | MAXXECUSTREE-C1-J4 | AIN 4 (0-5V) | analog_in | single_source | |
| OEM-A-21 | Diagnostic L-line | serial | — | — | — | single_source | |
| OEM-A-22 | Tachometer output | tacho_out | — | — | — | single_source | |
| OEM-A-23 | ECU main power (from engine-electronics relay) | power_in | MAXXECUSTREE-C1-M4 | +12V ECU power supply | power_in | single_source | |
| OEM-A-24 | Injector 1 (cyl 1) | injector_out | MAXXECUSTREE-C1-K1 | INJ 1 | injector_out | single_source | |
| OEM-A-25 | Injector 5 (cyl 5) | injector_out | MAXXECUSTREE-C1-M3 | INJ 5 | injector_out | single_source | |
| OEM-A-26 | Injector 3 (cyl 3) | injector_out | MAXXECUSTREE-C1-M1 | INJ 3 | injector_out | single_source | |
| OEM-A-27 | Idle air control valve | low_side_out | MAXXECUSTREE-C1-A4 | GPO 8/TACHO | low_side_out | single_source | |
| OEM-A-3 | Injector 2 (cyl 2) | injector_out | MAXXECUSTREE-C1-K2 | INJ 2 | injector_out | single_source | |
| OEM-A-31 | EVAP canister purge valve | low_side_out | MAXXECUSTREE-C1-D1 | WBO2 Heater- | low_side_out | single_source | |
| OEM-A-33 | Sensor ground bus | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | single_source | |
| OEM-A-34 | Knock sensor 1 | knock_in | — | — | — | single_source | |
| OEM-A-36 | Intake air temperature (IAT) | temp_in | MAXXECUSTREE-C1-F2 | IAT | temp_in | single_source | |
| OEM-A-37 | A/C compressor switch | digital_in | MAXXECUSTREE-C1-K4 | DIN 2 | digital_in | single_source | |
| OEM-A-38 | Ignition switch (run/start) | digital_in | — | — | — | single_source | |
| OEM-A-39 | A/C switch (cabin) | digital_in | — | — | — | single_source | |
| OEM-A-4 | Injector 4 (cyl 4) | injector_out | MAXXECUSTREE-C1-M2 | INJ 4 | injector_out | single_source | |
| OEM-A-40 | Throttle position sensor 1 | analog_in | MAXXECUSTREE-C1-G2 | TPS/AIN | analog_in | single_source | |
| OEM-A-41 | TPS power (+5V) | vref | MAXXECUSTREE-C1-G1 | +5V sensor supply | vref | single_source | |
| OEM-A-43 | Diagnostic K-line | serial | — | — | — | single_source | |
| OEM-A-44 | Camshaft position sensor (G40) | trigger_in | MAXXECUSTREE-C1-H4 | HOME | trigger_in | single_source | |
| OEM-A-49 | Secondary air injection relay control | low_side_out | MAXXECUSTREE-C1-B4 | GPO 1 | low_side_out | single_source | |
| OEM-A-5 | Check engine light (MIL) | low_side_out | — | — | — | single_source | |
| OEM-A-51 | MFA fuel-consumption signal | tacho_out | — | — | — | single_source | |
| OEM-A-52 | Ignition coil 4 (coil pack pin 4) | ignition_out | MAXXECUSTREE-C1-B2 | IGN 3 | ignition_out | single_source | |
| OEM-A-53 | Idle air control valve (2nd) | low_side_out | — | — | — | single_source | |
| OEM-A-54 | Battery constant (+12V) | power_in | — | — | — | single_source | |
| OEM-A-55 | Ground (E-3) | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | single_source | |
| OEM-A-56 | Ground (E-4) | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | single_source | |
| OEM-A-59 | Mass airflow sensor (5th terminal) | sensor_out | — | — | — | single_source | |
| OEM-A-6 | Fuel pump relay control | low_side_out | MAXXECUSTREE-C1-C4 | GPO 2 | low_side_out | single_source | |
| OEM-A-60 | Ignition coil 3 (coil pack pin 3) | ignition_out | MAXXECUSTREE-C1-A3 | IGN 2 | ignition_out | single_source | |
| OEM-A-65 | Vehicle speed sensor (VSS) | digital_in | MAXXECUSTREE-C1-K3 | DIN 1 | digital_in | single_source | |
| OEM-A-67 | Crank sensor return (VR-) | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | single_source | |
| OEM-A-68 | Crank position sensor (G28, VR+) | trigger_in | MAXXECUSTREE-C1-H3 | TRIGGER | trigger_in | single_source | |
| OEM-A-7 | Ground (E-2) | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | single_source | |
| OEM-A-8 | Ignition coil 2 (coil pack pin 2) | ignition_out | MAXXECUSTREE-C1-A2 | IGN 1 | ignition_out | single_source | |
| OEM-A-9 | Engine electronics relay control | low_side_out | MAXXECUSTREE-C1-D4 | GPO 3 | low_side_out | single_source |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-A-23 | SP-14V-1 | 0.85 | no route | ECU main power (from engine-electronics relay) | — | |
| W2 | SP-14V-1 | MAXXECUSTREE-C1-M4 | 0.85 | no route | +12V ECU power supply | — | |
| W3 | OEM-A-1 | SP-GND-1 | 0.85 | no route | Ground (E-1) | — | |
| W4 | OEM-A-10 | SP-GND-1 | 0.85 | no route | Ground (OBD1 EGR enable) | — | |
| W5 | OEM-A-55 | SP-GND-1 | 0.85 | no route | Ground (E-3) | — | |
| W6 | OEM-A-56 | SP-GND-1 | 0.85 | no route | Ground (E-4) | — | |
| W7 | OEM-A-7 | SP-GND-1 | 0.85 | no route | Ground (E-2) | — | |
| W8 | SP-GND-1 | MAXXECUSTREE-C1-L4 | 0.85 | no route | Engine GND | — | |
| W9 | OEM-A-16 | SP-0V-1 | 0.5 | no route | MAF ground | — | |
| W10 | OEM-A-33 | SP-0V-1 | 0.5 | no route | Sensor ground bus | — | |
| W11 | OEM-A-67 | SP-0V-1 | 0.5 | no route | Crank sensor return (VR-) | — | |
| W12 | SP-0V-1 | MAXXECUSTREE-C1-H1 | 0.5 | no route | Sensor GND | — | |
| W13 | SP-0V-1 | MAXXECUSTREE-C1-H2 | 0.5 | no route | Trigger GND | — | |
| W14 | OEM-A-41 | MAXXECUSTREE-C1-G1 | 0.5 | no route | TPS power (+5V) | — | |
| W15 | OEM-A-68 | MAXXECUSTREE-C1-H3 | 0.5 | no route | Crank position sensor (G28, VR+) | — | |
| W16 | OEM-A-44 | MAXXECUSTREE-C1-H4 | 0.5 | no route | Camshaft position sensor (G40) | — | |
| W17 | OEM-A-8 | MAXXECUSTREE-C1-A2 | 0.5 | no route | Ignition coil 2 (coil pack pin 2) | — | |
| W18 | OEM-A-60 | MAXXECUSTREE-C1-A3 | 0.5 | no route | Ignition coil 3 (coil pack pin 3) | — | |
| W19 | OEM-A-52 | MAXXECUSTREE-C1-B2 | 0.5 | no route | Ignition coil 4 (coil pack pin 4) | — | |
| W20 | OEM-A-24 | MAXXECUSTREE-C1-K1 | 0.5 | no route | Injector 1 (cyl 1) | — | |
| W21 | OEM-A-3 | MAXXECUSTREE-C1-K2 | 0.5 | no route | Injector 2 (cyl 2) | — | |
| W22 | OEM-A-26 | MAXXECUSTREE-C1-M1 | 0.5 | no route | Injector 3 (cyl 3) | — | |
| W23 | OEM-A-4 | MAXXECUSTREE-C1-M2 | 0.5 | no route | Injector 4 (cyl 4) | — | |
| W24 | OEM-A-25 | MAXXECUSTREE-C1-M3 | 0.5 | no route | Injector 5 (cyl 5) | — | |
| W25 | OEM-A-2 | MAXXECUSTREE-C1-L3 | 0.5 | no route | Injector 6 (cyl 6) | — | |
| W26 | OEM-A-17 | MAXXECUSTREE-C1-J3 | 0.5 | no route | MAF signal | — | |
| W27 | OEM-A-40 | MAXXECUSTREE-C1-G2 | 0.5 | no route | Throttle position sensor 1 | — | |
| W28 | OEM-A-14 | MAXXECUSTREE-C1-F1 | 0.5 | no route | Coolant temperature (CLT) | — | |
| W29 | OEM-A-49 | MAXXECUSTREE-C1-B4 | 0.5 | no route | Secondary air injection relay control | — | |
| W30 | OEM-A-6 | MAXXECUSTREE-C1-C4 | 0.5 | no route | Fuel pump relay control | — | |
| W31 | OEM-A-9 | MAXXECUSTREE-C1-D4 | 0.5 | no route | Engine electronics relay control | — | |
| W32 | OEM-A-27 | MAXXECUSTREE-C1-A4 | 0.5 | no route | Idle air control valve | — | |
| W33 | OEM-A-31 | MAXXECUSTREE-C1-D1 | 0.5 | no route | EVAP canister purge valve | — | |
| W34 | OEM-A-20 | MAXXECUSTREE-C1-J4 | 0.5 | no route | O2 sensor 1 (primary) | — | |
| W35 | OEM-A-15 | MAXXECUSTREE-C1-J1 | 0.5 | no route | EGR temperature sensor | — | |
| W36 | OEM-A-36 | MAXXECUSTREE-C1-F2 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W37 | OEM-A-65 | MAXXECUSTREE-C1-K3 | 0.5 | no route | Vehicle speed sensor (VSS) | — | |
| W38 | OEM-A-37 | MAXXECUSTREE-C1-K4 | 0.5 | no route | A/C compressor switch | — |
Bill of materials
| Category | Part number | Manufacturer | Description | Qty | Unit |
|---|
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 | REQUIRED_UNMAPPED | OEM-A-34 | Required OEM function "Knock sensor 1" (knock_in) is not connected to the new ECU. |
| error | REQUIRED_UNMAPPED | OEM-A-38 | Required OEM function "Ignition switch (run/start)" (digital_in) is not connected to the new ECU. |
| warn | LOAD_UNKNOWN | MAXXECUSTREE-C1-B4 | MAXXECUSTREE-C1-B4 "GPO 1" drives OEM-A-49 Secondary air injection relay control (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | MAXXECUSTREE-C1-C4 | MAXXECUSTREE-C1-C4 "GPO 2" drives OEM-A-6 Fuel pump relay control (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | MAXXECUSTREE-C1-D4 | MAXXECUSTREE-C1-D4 "GPO 3" drives OEM-A-9 Engine electronics relay control (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| info | UNMAPPED | OEM | 8 optional OEM pins are not mapped: OEM-A-21 Diagnostic L-line; OEM-A-22 Tachometer output; OEM-A-39 A/C switch (cabin); OEM-A-43 Diagnostic K-line; OEM-A-5 Check engine light (MIL); OEM-A-51 MFA fuel-consumption signal; OEM-A-53 Idle air control valve (2nd); OEM-A-59 Mass airflow sensor (5th terminal) |
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-A-54 | Battery-constant (memory) feed of the stock ECU: the new ECU has no such input, so it is not needed. | mapping-proposal |
Notes
Fit check: unconfirmed. Confirm these before building: - Trigger pattern for VW VR6 not found in the ECU's docs (No named VR6 pattern; 60-2 + hall cam via generic Missing-tooth + cam.) - No knock input; the stock knock sensor would be unused 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-A 34: Knock sensor 1: no free knock input on MaxxECU MaxxECU STREET - OEM-A 38: Ignition switch (run/start): 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 Not wired: - OEM-A 54: Battery constant (+12V): MaxxECU MaxxECU STREET has no battery-constant input; not needed - OEM-A 5: Check engine light (MIL): no free low_side/relay_control/heater_low_side/ls_hs/injector on MaxxECU MaxxECU STREET - OEM-A 53: Idle air control valve (2nd): no free low_side/relay_control/heater_low_side/ls_hs/injector on MaxxECU MaxxECU STREET - OEM-A 22: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on MaxxECU MaxxECU STREET - OEM-A 51: MFA fuel-consumption signal: no free tacho/frequency_out/low_side/ls_hs on MaxxECU MaxxECU STREET - OEM-A 39: A/C switch (cabin): no free switch_in/frequency_in/analog_0_5 on MaxxECU MaxxECU STREET - OEM-A 21: Diagnostic L-line: no free k_line on MaxxECU MaxxECU STREET - OEM-A 43: Diagnostic K-line: no free k_line on MaxxECU MaxxECU STREET - OEM-A 59: Mass airflow sensor (5th terminal): no rule for class sensor_signal; wire by hand
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 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 | a2resource: VR6/ABA Motronic M2.9 (OBD1) engine control unit pinout | http://www.a2resource.com/electrical/management/motronicvr6aba.html | — | — | — |