MX-5 Miata NA8 1994-95 (BP-ZE, 1.8, OBD-I) → MaxxECU MaxxECU STREET REV9+ (auto)
MX-5 Miata NA8 1994-95 (BP-ZE, 1.8, OBD-I) — MaxxECU — MaxxECU STREET
Drawn by Michael Gnankou · Rev 0 · proposal · 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 | proposal · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | none |
| Size of the job | 33 wires · 6 connectors · 2 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-1-B | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | SP-14V-1 | MAXXECUSTREE-C1-M4 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-2-A | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | OEM-2-B | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | SP-GND-1 | MAXXECUSTREE-C1-L4 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-2-C | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-2-D | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | OEM-2-F | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-0V-1 | MAXXECUSTREE-C1-H1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-0V-1 | MAXXECUSTREE-C1-H2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-2-K | MAXXECUSTREE-C1-G1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-2-E | MAXXECUSTREE-C1-H3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | OEM-2-G | MAXXECUSTREE-C1-H4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-1-G | MAXXECUSTREE-C1-A2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-1-H | MAXXECUSTREE-C1-A3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | OEM-2-U | MAXXECUSTREE-C1-K1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-2-V | MAXXECUSTREE-C1-K2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-2-Y | MAXXECUSTREE-C1-M1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-2-Z | MAXXECUSTREE-C1-M2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-2-O | MAXXECUSTREE-C1-J3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-2-M | MAXXECUSTREE-C1-G2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-2-Q | MAXXECUSTREE-C1-F1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-1-J | MAXXECUSTREE-C1-B4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-1-R | MAXXECUSTREE-C1-C4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-2-S | MAXXECUSTREE-C1-D4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-2-T | MAXXECUSTREE-C1-A4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-1-L | MAXXECUSTREE-C1-D1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-2-L | MAXXECUSTREE-C1-M3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-2-W | MAXXECUSTREE-C1-L3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-2-N | MAXXECUSTREE-C1-J4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-2-P | MAXXECUSTREE-C1-F2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-1-M | MAXXECUSTREE-C1-K3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-1-C | 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-M4 | MAXXECUSTREE-C1-H1 | open (OL) | +12 V supply must not touch sensor ground | |
| 2 | MAXXECUSTREE-C1-M4 | MAXXECUSTREE-C1-L4 | open (OL) | +12 V supply must not touch power ground | |
| 3 | MAXXECUSTREE-C1-H1 | MAXXECUSTREE-C1-G1 | open (OL) | sensor ground must not touch 5 V sensor reference | |
| 4 | MAXXECUSTREE-C1-L4 | MAXXECUSTREE-C1-G1 | open (OL) | power ground must not touch 5 V sensor reference | |
| 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 | — | W14 | — | 0.5 | OEM-1-G | — | — | — |
| A3 | IGN 2 | — | W15 | — | 0.5 | OEM-1-H | — | — | — |
| A4 | GPO 8/TACHO | — | W26 | — | 0.5 | OEM-2-T | — | — | — |
| B2 | IGN 3 | — | — | — | — | — | — | — | — |
| B3 | IGN 4 | — | — | — | — | — | — | — | — |
| B4 | GPO 1 | — | W23 | — | 0.5 | OEM-1-J | — | — | — |
| C2 | IGN 5 | — | — | — | — | — | — | — | — |
| C3 | IGN 6 | — | — | — | — | — | — | — | — |
| C4 | GPO 2 | — | W24 | — | 0.5 | OEM-1-R | — | — | — |
| D1 | WBO2 Heater- | — | W27 | — | 0.5 | OEM-1-L | — | — | — |
| D4 | GPO 3 | — | W25 | — | 0.5 | OEM-2-S | — | — | — |
| E1 | CAN H | — | — | — | — | — | — | — | — |
| E2 | CAN L | — | — | — | — | — | — | — | — |
| E3 | GND Shield | — | — | — | — | — | — | — | — |
| F1 | CLT | — | W22 | — | 0.5 | OEM-2-Q | — | — | — |
| F2 | IAT | — | W31 | — | 0.5 | OEM-2-P | — | — | — |
| F3 | WBO2 VREF | — | — | — | — | — | — | — | — |
| F4 | WBO2 VS | — | — | — | — | — | — | — | — |
| G1 | +5V sensor supply | — | W11 | — | 0.5 | OEM-2-K | — | — | — |
| G2 | TPS/AIN | — | W21 | — | 0.5 | OEM-2-M | — | — | — |
| G3 | WBO2 IP | — | — | — | — | — | — | — | — |
| G4 | WBO2 RCAL | — | — | — | — | — | — | — | — |
| H1 | Sensor GND | — | W9 | — | 0.5 | SP-0V-1 | — | — | — |
| H2 | Trigger GND | — | W10 | — | 0.5 | SP-0V-1 | — | — | — |
| H3 | TRIGGER | — | W12 | — | 0.5 | OEM-2-E | — | — | — |
| H4 | HOME | — | W13 | — | 0.5 | OEM-2-G | — | — | — |
| J1 | AIN 1 (temperature) | — | — | — | — | — | — | — | — |
| J2 | AIN 2 (Temperature) | — | — | — | — | — | — | — | — |
| J3 | AIN 3 (0-5V) | — | W20 | — | 0.5 | OEM-2-O | — | — | — |
| J4 | AIN 4 (0-5V) | — | W30 | — | 0.5 | OEM-2-N | — | — | — |
| K1 | INJ 1 | — | W16 | — | 0.5 | OEM-2-U | — | — | — |
| K2 | INJ 2 | — | W17 | — | 0.5 | OEM-2-V | — | — | — |
| K3 | DIN 1 | — | W32 | — | 0.5 | OEM-1-M | — | — | — |
| K4 | DIN 2 | — | W33 | — | 0.5 | OEM-1-C | — | — | — |
| L3 | INJ 6 | — | W29 | — | 0.5 | OEM-2-W | — | — | — |
| L4 | Engine GND | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| M1 | INJ 3 | — | W18 | — | 0.5 | OEM-2-Y | — | — | — |
| M2 | INJ 4 | — | W19 | — | 0.5 | OEM-2-Z | — | — | — |
| M3 | INJ 5 | — | W28 | — | 0.5 | OEM-2-L | — | — | — |
| M4 | +12V ECU power supply | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
OEM-1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Constant +12V | — | — | — | — | — | — | — | — |
| B | ECU power +14V (main relay) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| C | Start signal | — | W33 | — | 0.5 | MAXXECUSTREE-C1-K4 | — | — | — |
| D | Data link connector | — | — | — | — | — | — | — | — |
| E | Malfunction indicator lamp (MIL) | — | — | — | — | — | — | — | — |
| G | Ignition 1 (coils 1+4, wasted spark) | — | W14 | — | 0.5 | MAXXECUSTREE-C1-A2 | — | — | — |
| H | Ignition 2 (coils 2+3, wasted spark) | — | W15 | — | 0.5 | MAXXECUSTREE-C1-A3 | — | — | — |
| I | Powertrain control module (transmission) | — | — | — | — | — | — | — | — |
| J | A/C relay | — | W23 | — | 0.5 | MAXXECUSTREE-C1-B4 | — | — | — |
| L | Coolant fan relay | — | W27 | — | 0.5 | MAXXECUSTREE-C1-D1 | — | — | — |
| M | Vehicle speed | — | W32 | — | 0.5 | MAXXECUSTREE-C1-K3 | — | — | — |
| N | Powertrain control module (transmission) | — | — | — | — | — | — | — | — |
| O | Stop light switch | — | — | — | — | — | — | — | — |
| P | Power steering pressure switch | — | — | — | — | — | — | — | — |
| Q | A/C request | — | — | — | — | — | — | — | — |
| R | Cooling fan relay | — | W24 | — | 0.5 | MAXXECUSTREE-C1-C4 | — | — | — |
| S | Heater control unit | — | — | — | — | — | — | — | — |
| T | Unknown | — | — | — | — | — | — | — | — |
| U | Unknown | — | — | — | — | — | — | — | — |
| V | Neutral/clutch switch | — | — | — | — | — | — | — | — |
OEM-2
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Power ground | — | W3 | — | 0.85 | SP-GND-1 | — | — | — |
| B | Power ground | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| C | Sensor ground (E2) | — | W6 | — | 0.5 | SP-0V-1 | — | — | — |
| D | Sensor ground (E2) | — | W7 | — | 0.5 | SP-0V-1 | — | — | — |
| E | Crank position (CAS NE) | — | W12 | — | 0.5 | MAXXECUSTREE-C1-H3 | — | — | — |
| F | MAF ground | — | W8 | — | 0.5 | SP-0V-1 | — | — | — |
| G | Cam position (CAS G) | — | W13 | — | 0.5 | MAXXECUSTREE-C1-H4 | — | — | — |
| H | Data link connector | — | — | — | — | — | — | — | — |
| I | Tachometer output | — | — | — | — | — | — | — | — |
| J | EGR function sensor | — | — | — | — | — | — | — | — |
| K | +5V sensor supply | — | W11 | — | 0.5 | MAXXECUSTREE-C1-G1 | — | — | — |
| L | Rear defroster relay | — | W28 | — | 0.5 | MAXXECUSTREE-C1-M3 | — | — | — |
| M | Throttle position (TPS) | — | W21 | — | 0.5 | MAXXECUSTREE-C1-G2 | — | — | — |
| N | O2 sensor | — | W30 | — | 0.5 | MAXXECUSTREE-C1-J4 | — | — | — |
| O | Mass air flow (MAF) | — | W20 | — | 0.5 | MAXXECUSTREE-C1-J3 | — | — | — |
| P | Intake air temperature (IAT) | — | W31 | — | 0.5 | MAXXECUSTREE-C1-F2 | — | — | — |
| Q | Coolant temperature (ECT) | — | W22 | — | 0.5 | MAXXECUSTREE-C1-F1 | — | — | — |
| R | PRC solenoid (fuel pressure regulator) | — | — | — | — | — | — | — | — |
| S | Condenser fan relay | — | W25 | — | 0.5 | MAXXECUSTREE-C1-D4 | — | — | — |
| T | Fuel pump relay | — | W26 | — | 0.5 | MAXXECUSTREE-C1-A4 | — | — | — |
| U | Injector 1 | — | W16 | — | 0.5 | MAXXECUSTREE-C1-K1 | — | — | — |
| V | Injector 2 | — | W17 | — | 0.5 | MAXXECUSTREE-C1-K2 | — | — | — |
| W | ISC solenoid | — | W29 | — | 0.5 | MAXXECUSTREE-C1-L3 | — | — | — |
| X | Evap purge solenoid | — | — | — | — | — | — | — | — |
| Y | Injector 3 | — | W18 | — | 0.5 | MAXXECUSTREE-C1-M1 | — | — | — |
| Z | Injector 4 | — | W19 | — | 0.5 | MAXXECUSTREE-C1-M2 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W6 | — | 0.5 | OEM-2-C | — | — | — |
| 1 | — | — | W7 | — | 0.5 | OEM-2-D | — | — | — |
| 1 | — | — | W8 | — | 0.5 | OEM-2-F | — | — | — |
| 1 | — | — | W9 | — | 0.5 | MAXXECUSTREE-C1-H1 | — | — | — |
| 1 | — | — | W10 | — | 0.5 | MAXXECUSTREE-C1-H2 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-1-B | — | — | — |
| 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-2-A | — | — | — |
| 1 | — | — | W4 | — | 0.85 | OEM-2-B | — | — | — |
| 1 | — | — | W5 | — | 0.85 | MAXXECUSTREE-C1-L4 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-1-A | Constant +12V | power_in | — | — | — | LR | single_source |
| OEM-1-B | ECU power +14V (main relay) | power_in | MAXXECUSTREE-C1-M4 | +12V ECU power supply | power_in | WR | single_source |
| OEM-1-C | Start signal | digital_in | MAXXECUSTREE-C1-K4 | DIN 2 | digital_in | V | single_source |
| OEM-1-D | Data link connector | serial | — | — | — | WG | single_source |
| OEM-1-E | Malfunction indicator lamp (MIL) | low_side_out | — | — | — | YB | single_source |
| OEM-1-G | Ignition 1 (coils 1+4, wasted spark) | ignition_out | MAXXECUSTREE-C1-A2 | IGN 1 | ignition_out | BrY | single_source |
| OEM-1-H | Ignition 2 (coils 2+3, wasted spark) | ignition_out | MAXXECUSTREE-C1-A3 | IGN 2 | ignition_out | Br | single_source |
| OEM-1-I | Powertrain control module (transmission) | — | — | — | — | LW | single_source |
| OEM-1-J | A/C relay | low_side_out | MAXXECUSTREE-C1-B4 | GPO 1 | low_side_out | single_source | |
| OEM-1-L | Coolant fan relay | low_side_out | MAXXECUSTREE-C1-D1 | WBO2 Heater- | low_side_out | BG | single_source |
| OEM-1-M | Vehicle speed | digital_in | MAXXECUSTREE-C1-K3 | DIN 1 | digital_in | GR | single_source |
| OEM-1-N | Powertrain control module (transmission) | — | — | — | — | R | single_source |
| OEM-1-O | Stop light switch | digital_in | — | — | — | GB | single_source |
| OEM-1-P | Power steering pressure switch | digital_in | — | — | — | LY | single_source |
| OEM-1-Q | A/C request | digital_in | — | — | — | LgB | single_source |
| OEM-1-R | Cooling fan relay | low_side_out | MAXXECUSTREE-C1-C4 | GPO 2 | low_side_out | YB | single_source |
| OEM-1-S | Heater control unit | — | — | — | — | LOr | single_source |
| OEM-1-T | Unknown | — | — | — | — | YR | single_source |
| OEM-1-U | Unknown | — | — | — | — | RB | single_source |
| OEM-1-V | Neutral/clutch switch | digital_in | — | — | — | BrW | single_source |
| OEM-2-A | Power ground | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | B | single_source |
| OEM-2-B | Power ground | ground | MAXXECUSTREE-C1-L4 | Engine GND | ground | B | single_source |
| OEM-2-C | Sensor ground (E2) | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | BLg | corroborated |
| OEM-2-D | Sensor ground (E2) | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | BL | corroborated |
| OEM-2-E | Crank position (CAS NE) | trigger_in | MAXXECUSTREE-C1-H3 | TRIGGER | trigger_in | W | single_source |
| OEM-2-F | MAF ground | sensor_ground | MAXXECUSTREE-C1-H1 + MAXXECUSTREE-C1-H2 | Sensor GND + Trigger GND | sensor_ground | BR | single_source |
| OEM-2-G | Cam position (CAS G) | trigger_in | MAXXECUSTREE-C1-H4 | HOME | trigger_in | YL | single_source |
| OEM-2-H | Data link connector | serial | — | — | — | LgY | single_source |
| OEM-2-I | Tachometer output | tacho_out | — | — | — | BW | single_source |
| OEM-2-J | EGR function sensor | — | — | — | — | LgR | single_source |
| OEM-2-K | +5V sensor supply | vref | MAXXECUSTREE-C1-G1 | +5V sensor supply | vref | LgW | single_source |
| OEM-2-L | Rear defroster relay | low_side_out | MAXXECUSTREE-C1-M3 | INJ 5 | injector_out | LR | single_source |
| OEM-2-M | Throttle position (TPS) | analog_in | MAXXECUSTREE-C1-G2 | TPS/AIN | analog_in | RB | single_source |
| OEM-2-N | O2 sensor | lambda_nb_in | MAXXECUSTREE-C1-J4 | AIN 4 (0-5V) | analog_in | RL | single_source |
| OEM-2-O | Mass air flow (MAF) | analog_in | MAXXECUSTREE-C1-J3 | AIN 3 (0-5V) | analog_in | R | single_source |
| OEM-2-P | Intake air temperature (IAT) | temp_in | MAXXECUSTREE-C1-F2 | IAT | temp_in | RB | single_source |
| OEM-2-Q | Coolant temperature (ECT) | temp_in | MAXXECUSTREE-C1-F1 | CLT | temp_in | LW | single_source |
| OEM-2-R | PRC solenoid (fuel pressure regulator) | low_side_out | — | — | — | YG | single_source |
| OEM-2-S | Condenser fan relay | low_side_out | MAXXECUSTREE-C1-D4 | GPO 3 | low_side_out | LW | single_source |
| OEM-2-T | Fuel pump relay | low_side_out | MAXXECUSTREE-C1-A4 | GPO 8/TACHO | low_side_out | Lg | single_source |
| OEM-2-U | Injector 1 | injector_out | MAXXECUSTREE-C1-K1 | INJ 1 | injector_out | Y | single_source |
| OEM-2-V | Injector 2 | injector_out | MAXXECUSTREE-C1-K2 | INJ 2 | injector_out | YB | single_source |
| OEM-2-W | ISC solenoid | low_side_out | MAXXECUSTREE-C1-L3 | INJ 6 | injector_out | LOr | single_source |
| OEM-2-X | Evap purge solenoid | low_side_out | — | — | — | YR | single_source |
| OEM-2-Y | Injector 3 | injector_out | MAXXECUSTREE-C1-M1 | INJ 3 | injector_out | GW | single_source |
| OEM-2-Z | Injector 4 | injector_out | MAXXECUSTREE-C1-M2 | INJ 4 | injector_out | G | single_source |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-1-B | SP-14V-1 | 0.85 | no route | ECU power +14V (main relay) | — | |
| W2 | SP-14V-1 | MAXXECUSTREE-C1-M4 | 0.85 | no route | +12V ECU power supply | — | |
| W3 | OEM-2-A | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W4 | OEM-2-B | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W5 | SP-GND-1 | MAXXECUSTREE-C1-L4 | 0.85 | no route | Engine GND | — | |
| W6 | OEM-2-C | SP-0V-1 | 0.5 | no route | Sensor ground (E2) | — | |
| W7 | OEM-2-D | SP-0V-1 | 0.5 | no route | Sensor ground (E2) | — | |
| W8 | OEM-2-F | SP-0V-1 | 0.5 | no route | MAF ground | — | |
| W9 | SP-0V-1 | MAXXECUSTREE-C1-H1 | 0.5 | no route | Sensor GND | — | |
| W10 | SP-0V-1 | MAXXECUSTREE-C1-H2 | 0.5 | no route | Trigger GND | — | |
| W11 | OEM-2-K | MAXXECUSTREE-C1-G1 | 0.5 | no route | +5V sensor supply | — | |
| W12 | OEM-2-E | MAXXECUSTREE-C1-H3 | 0.5 | no route | Crank position (CAS NE) | — | |
| W13 | OEM-2-G | MAXXECUSTREE-C1-H4 | 0.5 | no route | Cam position (CAS G) | — | |
| W14 | OEM-1-G | MAXXECUSTREE-C1-A2 | 0.5 | no route | Ignition 1 (coils 1+4, wasted spark) | — | |
| W15 | OEM-1-H | MAXXECUSTREE-C1-A3 | 0.5 | no route | Ignition 2 (coils 2+3, wasted spark) | — | |
| W16 | OEM-2-U | MAXXECUSTREE-C1-K1 | 0.5 | no route | Injector 1 | — | |
| W17 | OEM-2-V | MAXXECUSTREE-C1-K2 | 0.5 | no route | Injector 2 | — | |
| W18 | OEM-2-Y | MAXXECUSTREE-C1-M1 | 0.5 | no route | Injector 3 | — | |
| W19 | OEM-2-Z | MAXXECUSTREE-C1-M2 | 0.5 | no route | Injector 4 | — | |
| W20 | OEM-2-O | MAXXECUSTREE-C1-J3 | 0.5 | no route | Mass air flow (MAF) | — | |
| W21 | OEM-2-M | MAXXECUSTREE-C1-G2 | 0.5 | no route | Throttle position (TPS) | — | |
| W22 | OEM-2-Q | MAXXECUSTREE-C1-F1 | 0.5 | no route | Coolant temperature (ECT) | — | |
| W23 | OEM-1-J | MAXXECUSTREE-C1-B4 | 0.5 | no route | A/C relay | — | |
| W24 | OEM-1-R | MAXXECUSTREE-C1-C4 | 0.5 | no route | Cooling fan relay | — | |
| W25 | OEM-2-S | MAXXECUSTREE-C1-D4 | 0.5 | no route | Condenser fan relay | — | |
| W26 | OEM-2-T | MAXXECUSTREE-C1-A4 | 0.5 | no route | Fuel pump relay | — | |
| W27 | OEM-1-L | MAXXECUSTREE-C1-D1 | 0.5 | no route | Coolant fan relay | — | |
| W28 | OEM-2-L | MAXXECUSTREE-C1-M3 | 0.5 | no route | Rear defroster relay | — | |
| W29 | OEM-2-W | MAXXECUSTREE-C1-L3 | 0.5 | no route | ISC solenoid | — | |
| W30 | OEM-2-N | MAXXECUSTREE-C1-J4 | 0.5 | no route | O2 sensor | — | |
| W31 | OEM-2-P | MAXXECUSTREE-C1-F2 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W32 | OEM-1-M | MAXXECUSTREE-C1-K3 | 0.5 | no route | Vehicle speed | — | |
| W33 | OEM-1-C | MAXXECUSTREE-C1-K4 | 0.5 | no route | Start signal | — |
Bill of materials
| Category | Part number | Manufacturer | Description | Qty | Unit |
|---|---|---|---|---|---|
| connector | 174515-6 | TE | AMP Multilock .040/.070 hybrid 22-pin female harness plug (Miata NA/NB ECU) | 1.000 | ea |
| connector | 174516-6 | TE | AMP Multilock .040/.070 hybrid 26-pin female harness plug (Miata NA/NB ECU) | 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 (7)
| Severity | Code | Subject | Message |
|---|---|---|---|
| warn | LOAD_UNKNOWN | MAXXECUSTREE-C1-A4 | MAXXECUSTREE-C1-A4 "GPO 8/TACHO" drives OEM-2-T Fuel pump relay (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | MAXXECUSTREE-C1-B4 | MAXXECUSTREE-C1-B4 "GPO 1" drives OEM-1-J A/C relay (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-1-R Cooling fan relay (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-2-S Condenser fan relay (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| info | NET_FAMILY | OEM-2-L ↔ MAXXECUSTREE-C1-M3 | OEM-2-L "Rear defroster relay" [low_side_out] is wired to MAXXECUSTREE-C1-M3 "INJ 5" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency. |
| info | NET_FAMILY | OEM-2-W ↔ MAXXECUSTREE-C1-L3 | OEM-2-W "ISC solenoid" [low_side_out] is wired to MAXXECUSTREE-C1-L3 "INJ 6" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency. |
| info | UNMAPPED | OEM | 16 optional OEM pins are not mapped: OEM-1-D Data link connector; OEM-1-E Malfunction indicator lamp (MIL); OEM-1-I Powertrain control module (transmission); OEM-1-N Powertrain control module (transmission); OEM-1-O Stop light switch; OEM-1-P Power steering pressure switch; OEM-1-Q A/C request; OEM-1-S Heater control unit; OEM-1-T Unknown; OEM-1-U Unknown; OEM-1-V Neutral/clutch switch; OEM-2-H Data link connector; OEM-2-I Tachometer output; OEM-2-J EGR function sensor; OEM-2-R PRC solenoid (fuel pressure regulator); OEM-2-X Evap purge solenoid |
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-1-A | 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. Not wired: - OEM-1 A: Constant +12V: MaxxECU MaxxECU STREET has no battery-constant input; not needed - OEM-1 E: Malfunction indicator lamp (MIL): no free low_side/relay_control/heater_low_side/ls_hs/injector on MaxxECU MaxxECU STREET - OEM-2 R: PRC solenoid (fuel pressure regulator): no free low_side/relay_control/heater_low_side/ls_hs/injector on MaxxECU MaxxECU STREET - OEM-2 X: Evap purge solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on MaxxECU MaxxECU STREET - OEM-2 I: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on MaxxECU MaxxECU STREET - OEM-1 O: Stop light switch: no free switch_in/frequency_in/analog_0_5 on MaxxECU MaxxECU STREET - OEM-1 P: Power steering pressure switch: no free switch_in/frequency_in/analog_0_5 on MaxxECU MaxxECU STREET - OEM-1 Q: A/C request: no free switch_in/frequency_in/analog_0_5 on MaxxECU MaxxECU STREET - OEM-1 V: Neutral/clutch switch: no free switch_in/frequency_in/analog_0_5 on MaxxECU MaxxECU STREET - OEM-1 D: Data link connector: no free k_line on MaxxECU MaxxECU STREET - OEM-2 H: Data link connector: no free k_line on MaxxECU MaxxECU STREET - OEM-1 I: Powertrain control module (transmission): not classified in the library; wire by hand - OEM-1 N: Powertrain control module (transmission): not classified in the library; wire by hand - OEM-1 S: Heater control unit: not classified in the library; wire by hand - OEM-1 T: Unknown: not classified in the library; wire by hand - OEM-1 U: Unknown: not classified in the library; wire by hand - OEM-2 J: EGR function sensor: not classified in the library; wire by hand
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | Link G4X MX5X install manual (NA 1.6/1.8) | https://linkecu.com/documentation/MX5X.pdf | archive | 2026-10-05 | b7f730de9f6e |
| 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 | expert_report | Justin Barrera — Miata NA/NB wiring corrections | — | — | — | — |
| 2 | community_copy | rusefi wiki: 1994 Mazda Miata 1.8 (NA8) ECU pinout | https://github.com/rusefi/rusefi/wiki/Mazda-Miata-1994 | — | 2026-10-08 | 075801b907f4 |