MX-5 Miata NB2 2001-05 (BP-Z3, VVT; excludes Mazdaspeed) → DTAFast T2 (auto)
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.
Install modifications
Steps on the car itself, outside the harness. Every harness for this car inherits them.
- Re-route the pressure-sensor vacuum hose to the intake manifoldrequired
Re-route the pressure sensor's (Mazda "EGR boost sensor", pin 4AE) vacuum hose directly to the intake manifold, bypassing the EGR boost solenoid. The stock ECU multiplexes baro + MAP through that solenoid: with it off the sensor reads atmosphere, with it energized it reads manifold. After re-routing the sensor reads MAP only, so the standalone needs its own barometric source — its onboard baro sensor if fitted, or a separate baro sensor on a spare analog input. (Alternative, not recommended: keep the hose stock and have the ECU energize the solenoid permanently via a low-side output switched with ignition; this costs an output.)
Why: With the solenoid off (its default) the sensor reads atmospheric pressure, not manifold pressure, so a standalone that uses this sensor as its MAP input would read the wrong value.
Where: EGR boost solenoid and the pressure sensor's vacuum hose (sensor signal 4AE).
Source: Justin Barrera — Miata NA/NB wiring corrections
| 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 | 37 wires · 7 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-2-P | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | OEM-4-AF | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-4-D | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | SP-14V-1 | T2-C1-31 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | OEM-4-AG | T2-C1-21 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-3-A | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-3-B | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | OEM-4-A | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-GND-1 | T2-C1-13 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-GND-1 | T2-C1-14 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-4-O | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | SP-0V-1 | T2-C1-28 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | SP-0V-1 | T2-C1-29 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-4-L | T2-C1-27 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-3-Y | T2-C1-19 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | OEM-3-V | T2-C1-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-3-F | T2-C1-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-3-I | T2-C1-6 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-2-A | T2-C1-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-2-D | T2-C1-9 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-2-G | T2-C1-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-2-J | T2-C1-9 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-4-X | T2-C1-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-4-V | T2-C1-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-4-P | T2-C1-24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-2-B | T2-C1-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-2-C | T2-C1-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-2-K | T2-C1-18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-2-M | T2-C1-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-3-H | T2-C1-15 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-4-AE | T2-C1-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-4-AA | T2-C1-25 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-4-W | T2-C1-33 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-4-N | T2-C1-32 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-4-AD | T2-C1-34 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-3-T | T2-C1-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-3-S | T2-C1-30 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ |
Bench test (before first power-up)
Pre-power install steps (make these cuts/modifications on the car first, then verify the checks below): Re-route the pressure-sensor vacuum hose to the intake manifold.
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 | T2-C1-21 | T2-C1-28 | open (OL) | +12 V supply must not touch sensor ground | |
| 2 | T2-C1-27 | T2-C1-28 | open (OL) | 5 V sensor reference must not touch sensor ground | |
| 3 | T2-C1-31 | T2-C1-13 | open (OL) | +12 V supply must not touch power ground | |
| 4 | T2-C1-31 | T2-C1-28 | open (OL) | +12 V supply must not touch sensor ground | |
| 5 | T2-C1-13 | T2-C1-21 | open (OL) | power ground must not touch +12 V supply | |
| 6 | T2-C1-13 | T2-C1-27 | open (OL) | power ground must not touch 5 V sensor reference | |
| 7 | T2-C1-21 | T2-C1-27 | open (OL) | +12 V supply must not touch 5 V sensor reference | |
| 8 | T2-C1-31 | T2-C1-27 | 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
OEM-2
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Injector 1 | — | W19 | — | 0.5 | T2-C1-8 | — | — | — |
| B | Cooling fan relay | — | W26 | — | 0.5 | T2-C1-1 | — | — | — |
| C | Condenser fan relay | — | W27 | — | 0.5 | T2-C1-10 | — | — | — |
| D | Injector 2 | — | W20 | — | 0.5 | T2-C1-9 | — | — | — |
| E | EGR valve | — | — | — | — | — | — | — | — |
| F | EGR valve | — | — | — | — | — | — | — | — |
| G | Injector 3 | — | W21 | — | 0.5 | T2-C1-8 | — | — | — |
| H | EGR valve | — | — | — | — | — | — | — | — |
| I | EGR valve | — | — | — | — | — | — | — | — |
| J | Injector 4 | — | W22 | — | 0.5 | T2-C1-9 | — | — | — |
| K | A/C clutch relay | — | W28 | — | 0.5 | T2-C1-18 | — | — | — |
| L | NC | — | — | — | — | — | — | — | — |
| M | Fuel pump relay | — | W29 | — | 0.5 | T2-C1-26 | — | — | — |
| N | VTCS solenoid (intake butterflies) | — | — | — | — | — | — | — | — |
| O | Fuel pump relay (non-immobiliser) | — | — | — | — | — | — | — | — |
| P | ISC valve +14V feed | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| Q | ISC valve low side | — | — | — | — | — | — | — | — |
| R | Malfunction indicator lamp (MIL) | — | — | — | — | — | — | — | — |
OEM-3
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Power ground | — | W6 | — | 0.85 | SP-GND-1 | — | — | — |
| B | Power ground | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| C | Purge solenoid valve | — | — | — | — | — | — | — | — |
| D | EGR boost solenoid | — | — | — | — | — | — | — | — |
| E | NC | — | — | — | — | — | — | — | — |
| F | Ignition 1 (coils 1+4, wasted spark) | — | W17 | — | 0.5 | T2-C1-3 | — | — | — |
| G | NC | — | — | — | — | — | — | — | — |
| H | Main relay | — | W30 | — | 0.5 | T2-C1-15 | — | — | — |
| I | Ignition 2 (coils 2+3, wasted spark) | — | W18 | — | 0.5 | T2-C1-6 | — | — | — |
| J | Front O2 heater | — | — | — | — | — | — | — | — |
| K | EVAP leak detection pump | — | — | — | — | — | — | — | — |
| L | NC | — | — | — | — | — | — | — | — |
| M | Alternator control | — | — | — | — | — | — | — | — |
| N | NC | — | — | — | — | — | — | — | — |
| O | Tachometer output | — | — | — | — | — | — | — | — |
| P | Rear O2 heater | — | — | — | — | — | — | — | — |
| Q | Data link connector (K-line) | — | — | — | — | — | — | — | — |
| R | NC | — | — | — | — | — | — | — | — |
| S | Immobiliser | — | W37 | — | 0.5 | T2-C1-30 | — | — | — |
| T | Vehicle speed | — | W36 | — | 0.5 | T2-C1-11 | — | — | — |
| U | Charge lamp | — | — | — | — | — | — | — | — |
| V | Cam position (CMP) | — | W16 | — | 0.5 | T2-C1-12 | — | — | — |
| W | NC | — | — | — | — | — | — | — | — |
| X | NC | — | — | — | — | — | — | — | — |
| Y | Crank position (CKP) | — | W15 | — | 0.5 | T2-C1-19 | — | — | — |
| Z | NC | — | — | — | — | — | — | — | — |
OEM-4
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Power ground | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| AA | Rear O2 signal | — | W32 | — | 0.5 | T2-C1-25 | — | — | — |
| AB | NC | — | — | — | — | — | — | — | — |
| AC | TCM (automatic only) | — | — | — | — | — | — | — | — |
| AD | Fuel level | — | W35 | — | 0.5 | T2-C1-34 | — | — | — |
| AE | Pressure sensor (Mazda: EGR boost sensor) | — | W31 | — | 0.5 | T2-C1-23 | — | — | — |
| AF | ECU power +14V (main relay) | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| AG | Constant +12V | — | W5 | — | 0.85 | T2-C1-21 | — | — | — |
| AH | EVAP leak detection pump solenoid valve | — | — | — | — | — | — | — | — |
| B | Brake switch | — | — | — | — | — | — | — | — |
| C | Power steering pressure switch | — | — | — | — | — | — | — | — |
| D | VVT oil-control solenoid +12V feed | — | W3 | — | 0.85 | SP-14V-1 | — | — | — |
| E | Diagnostic (DLC TEN) (NA) | — | — | — | — | — | — | — | — |
| F | A/C request | — | — | — | — | — | — | — | — |
| G | NC | — | — | — | — | — | — | — | — |
| H | Neutral switch | — | — | — | — | — | — | — | — |
| I | Clutch switch | — | — | — | — | — | — | — | — |
| J | VTCS vacuum switch | — | — | — | — | — | — | — | — |
| K | NC | — | — | — | — | — | — | — | — |
| L | +5V sensor supply | — | W14 | — | 0.5 | T2-C1-27 | — | — | — |
| M | Knock sensor | — | — | — | — | — | — | — | — |
| N | Intake air temperature (IAT) | — | W34 | — | 0.5 | T2-C1-32 | — | — | — |
| O | Signal ground | — | W11 | — | 0.5 | SP-0V-1 | — | — | — |
| P | Coolant temperature (ECT) | — | W25 | — | 0.5 | T2-C1-24 | — | — | — |
| Q | NC | — | — | — | — | — | — | — | — |
| R | VVT oil-control solenoid (low-side control) | — | — | — | — | — | — | — | — |
| S | Ignition switch (IG1) sense | — | — | — | — | — | — | — | — |
| T | Generator output voltage (terminal P) | — | — | — | — | — | — | — | — |
| U | NC | — | — | — | — | — | — | — | — |
| V | Throttle position (TPS) | — | W24 | — | 0.5 | T2-C1-22 | — | — | — |
| W | Front O2 signal | — | W33 | — | 0.5 | T2-C1-33 | — | — | — |
| X | Mass air flow (MAF) | — | W23 | — | 0.5 | T2-C1-20 | — | — | — |
| Y | NC | — | — | — | — | — | — | — | — |
| Z | TCM (automatic only) | — | — | — | — | — | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W11 | — | 0.5 | OEM-4-O | — | — | — |
| 1 | — | — | W12 | — | 0.5 | T2-C1-28 | — | — | — |
| 1 | — | — | W13 | — | 0.5 | T2-C1-29 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-2-P | — | — | — |
| 1 | — | — | W2 | — | 0.85 | OEM-4-AF | — | — | — |
| 1 | — | — | W3 | — | 0.85 | OEM-4-D | — | — | — |
| 1 | — | — | W4 | — | 0.85 | T2-C1-31 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W6 | — | 0.85 | OEM-3-A | — | — | — |
| 1 | — | — | W7 | — | 0.85 | OEM-3-B | — | — | — |
| 1 | — | — | W8 | — | 0.85 | OEM-4-A | — | — | — |
| 1 | — | — | W9 | — | 0.85 | T2-C1-13 | — | — | — |
| 1 | — | — | W10 | — | 0.85 | T2-C1-14 | — | — | — |
T2-C1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | PWM 1 | — | W26 | — | 0.5 | OEM-2-B | — | — | — |
| 2 | Lambda Nernst Voltage | — | — | — | — | — | — | — | — |
| 3 | Coil 1 | — | W17 | — | 0.5 | OEM-3-F | — | — | — |
| 4 | Lambda VGND | — | — | — | — | — | — | — | — |
| 5 | Lambda Pump Current | — | — | — | — | — | — | — | — |
| 6 | Coil 2 | — | W18 | — | 0.5 | OEM-3-I | — | — | — |
| 7 | Lambda Trim Resistor | — | — | — | — | — | — | — | — |
| 8 | Injector 1 | — | W21 | — | 0.5 | OEM-2-G | — | — | — |
| 8 | Injector 1 | — | W19 | — | 0.5 | OEM-2-A | — | — | — |
| 9 | Injector 2 | — | W22 | — | 0.5 | OEM-2-J | — | — | — |
| 9 | Injector 2 | — | W20 | — | 0.5 | OEM-2-D | — | — | — |
| 10 | PWM 2 | — | W27 | — | 0.5 | OEM-2-C | — | — | — |
| 11 | Digital 1 | — | W36 | — | 0.5 | OEM-3-T | — | — | — |
| 12 | Wheel 1 | — | W16 | — | 0.5 | OEM-3-V | — | — | — |
| 13 | Power Ground 1 | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
| 14 | Power Ground 2 | — | W10 | — | 0.85 | SP-GND-1 | — | — | — |
| 15 | Lambda Heater Negative | — | W30 | — | 0.5 | OEM-3-H | — | — | — |
| 16 | CAN High | — | — | — | — | — | — | — | — |
| 17 | CAN Low | — | — | — | — | — | — | — | — |
| 18 | PWM 3 | — | W28 | — | 0.5 | OEM-2-K | — | — | — |
| 19 | Crank | — | W15 | — | 0.5 | OEM-3-Y | — | — | — |
| 20 | Analogue 1 | — | W23 | — | 0.5 | OEM-4-X | — | — | — |
| 21 | Permanent 12v | — | W5 | — | 0.85 | OEM-4-AG | — | — | — |
| 22 | Analogue 2 | — | W24 | — | 0.5 | OEM-4-V | — | — | — |
| 23 | Analogue 3 | — | W31 | — | 0.5 | OEM-4-AE | — | — | — |
| 24 | Thermistor 1 | — | W25 | — | 0.5 | OEM-4-P | — | — | — |
| 25 | Analogue 4 | — | W32 | — | 0.5 | OEM-4-AA | — | — | — |
| 26 | PWM 4 | — | W29 | — | 0.5 | OEM-2-M | — | — | — |
| 27 | 5v Output | — | W14 | — | 0.5 | OEM-4-L | — | — | — |
| 28 | Sensor Ground | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| 29 | Sensor Ground | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 30 | Digital 2 | — | W37 | — | 0.5 | OEM-3-S | — | — | — |
| 31 | Ignition 12v In | — | W4 | — | 0.85 | SP-14V-1 | — | — | — |
| 32 | Thermistor 2 | — | W34 | — | 0.5 | OEM-4-N | — | — | — |
| 33 | Analogue 5 | — | W33 | — | 0.5 | OEM-4-W | — | — | — |
| 34 | Analogue 6 | — | W35 | — | 0.5 | OEM-4-AD | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-2-A | Injector 1 | injector_out | T2-C1-8 | Injector 1 | injector_out | YB | single_source |
| OEM-2-B | Cooling fan relay | low_side_out | T2-C1-1 | PWM 1 | low_side_out | RY | single_source |
| OEM-2-C | Condenser fan relay | low_side_out | T2-C1-10 | PWM 2 | low_side_out | LW | single_source |
| OEM-2-D | Injector 2 | injector_out | T2-C1-9 | Injector 2 | injector_out | VG | single_source |
| OEM-2-E | EGR valve | low_side_out | — | — | — | Lg | single_source |
| OEM-2-F | EGR valve | low_side_out | — | — | — | WG | single_source |
| OEM-2-G | Injector 3 | injector_out | T2-C1-8 | Injector 1 | injector_out | YR | single_source |
| OEM-2-H | EGR valve | low_side_out | — | — | — | PB | single_source |
| OEM-2-I | EGR valve | low_side_out | — | — | — | P | single_source |
| OEM-2-J | Injector 4 | injector_out | T2-C1-9 | Injector 2 | injector_out | YG | single_source |
| OEM-2-K | A/C clutch relay | low_side_out | T2-C1-18 | PWM 3 | low_side_out | LB | single_source |
| OEM-2-L | NC | — | — | — | — | unverified | |
| OEM-2-M | Fuel pump relay | low_side_out | T2-C1-26 | PWM 4 | low_side_out | RW | single_source |
| OEM-2-N | VTCS solenoid (intake butterflies) | low_side_out | — | — | — | BW | single_source |
| OEM-2-O | Fuel pump relay (non-immobiliser) | low_side_out | — | — | — | R | single_source |
| OEM-2-P | ISC valve +14V feed | power_in | T2-C1-31 | Ignition 12v In | power_in | Or | single_source |
| OEM-2-Q | ISC valve low side | low_side_out | — | — | — | VR | single_source |
| OEM-2-R | Malfunction indicator lamp (MIL) | low_side_out | — | — | — | WL | single_source |
| OEM-3-A | Power ground | ground | T2-C1-13 + T2-C1-14 | Power Ground 1 + Power Ground 2 | ground | B | single_source |
| OEM-3-B | Power ground | ground | T2-C1-13 + T2-C1-14 | Power Ground 1 + Power Ground 2 | ground | BR | single_source |
| OEM-3-C | Purge solenoid valve | low_side_out | — | — | — | GY | single_source |
| OEM-3-D | EGR boost solenoid | — | — | — | — | GyB | single_source |
| OEM-3-E | NC | — | — | — | — | unverified | |
| OEM-3-F | Ignition 1 (coils 1+4, wasted spark) | ignition_out | T2-C1-3 | Coil 1 | ignition_out | BrW | single_source |
| OEM-3-G | NC | — | — | — | — | unverified | |
| OEM-3-H | Main relay | low_side_out | T2-C1-15 | Lambda Heater Negative | low_side_out | LOr | single_source |
| OEM-3-I | Ignition 2 (coils 2+3, wasted spark) | ignition_out | T2-C1-6 | Coil 2 | ignition_out | BY | single_source |
| OEM-3-J | Front O2 heater | low_side_out | — | — | — | BOr | single_source |
| OEM-3-K | EVAP leak detection pump | low_side_out | — | — | — | YB | single_source |
| OEM-3-L | NC | — | — | — | — | unverified | |
| OEM-3-M | Alternator control | low_side_out | — | — | — | GyR | single_source |
| OEM-3-N | NC | — | — | — | — | unverified | |
| OEM-3-O | Tachometer output | tacho_out | — | — | — | GOr | single_source |
| OEM-3-P | Rear O2 heater | low_side_out | — | — | — | WB | single_source |
| OEM-3-Q | Data link connector (K-line) | serial | — | — | — | GW | single_source |
| OEM-3-R | NC | — | — | — | — | unverified | |
| OEM-3-S | Immobiliser | digital_in | T2-C1-30 | Digital 2 | digital_in | RB | single_source |
| OEM-3-T | Vehicle speed | digital_in | T2-C1-11 | Digital 1 | digital_in | GR | single_source |
| OEM-3-U | Charge lamp | low_side_out | — | — | — | BrR | single_source |
| OEM-3-V | Cam position (CMP) | trigger_in | T2-C1-12 | Wheel 1 | digital_in | GyL | single_source |
| OEM-3-W | NC | — | — | — | — | unverified | |
| OEM-3-X | NC | — | — | — | — | unverified | |
| OEM-3-Y | Crank position (CKP) | trigger_in | T2-C1-19 | Crank | trigger_in | VW | single_source |
| OEM-3-Z | NC | — | — | — | — | unverified | |
| OEM-4-A | Power ground | ground | T2-C1-13 + T2-C1-14 | Power Ground 1 + Power Ground 2 | ground | BL | single_source |
| OEM-4-AA | Rear O2 signal | lambda_nb_in | T2-C1-25 | Analogue 4 | analog_in | R | single_source |
| OEM-4-AB | NC | — | — | — | — | unverified | |
| OEM-4-AC | TCM (automatic only) | — | — | — | — | VG | single_source |
| OEM-4-AD | Fuel level | analog_in | T2-C1-34 | Analogue 6 | analog_in | BrB | single_source |
| OEM-4-AE | Pressure sensor (Mazda: EGR boost sensor) | analog_in | T2-C1-23 | Analogue 3 | analog_in | LY | corroborated |
| OEM-4-AF | ECU power +14V (main relay) | power_in | T2-C1-31 | Ignition 12v In | power_in | WR | single_source |
| OEM-4-AG | Constant +12V | power_in | T2-C1-21 | Permanent 12v | power_in | LR | single_source |
| OEM-4-AH | EVAP leak detection pump solenoid valve | low_side_out | — | — | — | RG | single_source |
| OEM-4-B | Brake switch | digital_in | — | — | — | G | single_source |
| OEM-4-C | Power steering pressure switch | digital_in | — | — | — | Br | single_source |
| OEM-4-D | VVT oil-control solenoid +12V feed | power_in | T2-C1-31 | Ignition 12v In | power_in | Y | single_source |
| OEM-4-E | Diagnostic (DLC TEN) (NA) | serial | — | — | — | LY | single_source |
| OEM-4-F | A/C request | digital_in | — | — | — | LgB | single_source |
| OEM-4-G | NC | — | — | — | — | unverified | |
| OEM-4-H | Neutral switch | digital_in | — | — | — | V | single_source |
| OEM-4-I | Clutch switch | digital_in | — | — | — | WG | single_source |
| OEM-4-J | VTCS vacuum switch | digital_in | — | — | — | Or | single_source |
| OEM-4-K | NC | — | — | — | — | unverified | |
| OEM-4-L | +5V sensor supply | vref | T2-C1-27 | 5v Output | vref | LgR | single_source |
| OEM-4-M | Knock sensor | knock_in | — | — | — | W | single_source |
| OEM-4-N | Intake air temperature (IAT) | temp_in | T2-C1-32 | Thermistor 2 | temp_in | PL | single_source |
| OEM-4-O | Signal ground | sensor_ground | T2-C1-28 + T2-C1-29 | Sensor Ground + Sensor Ground | sensor_ground | BR | single_source |
| OEM-4-P | Coolant temperature (ECT) | temp_in | T2-C1-24 | Thermistor 1 | temp_in | RL | single_source |
| OEM-4-Q | NC | — | — | — | — | unverified | |
| OEM-4-R | VVT oil-control solenoid (low-side control) | low_side_out | — | — | — | VY | corroborated |
| OEM-4-S | Ignition switch (IG1) sense | digital_in | — | — | — | BW | single_source |
| OEM-4-T | Generator output voltage (terminal P) | — | — | — | — | Gy | single_source |
| OEM-4-U | NC | — | — | — | — | unverified | |
| OEM-4-V | Throttle position (TPS) | analog_in | T2-C1-22 | Analogue 2 | analog_in | GB | single_source |
| OEM-4-W | Front O2 signal | lambda_nb_in | T2-C1-33 | Analogue 5 | analog_in | L | single_source |
| OEM-4-X | Mass air flow (MAF) | analog_in | T2-C1-20 | Analogue 1 | analog_in | P | single_source |
| OEM-4-Y | NC | — | — | — | — | unverified | |
| OEM-4-Z | TCM (automatic only) | — | — | — | — | PB | single_source |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-2-P | SP-14V-1 | 0.85 | no route | ISC valve +14V feed | — | |
| W2 | OEM-4-AF | SP-14V-1 | 0.85 | no route | ECU power +14V (main relay) | — | |
| W3 | OEM-4-D | SP-14V-1 | 0.85 | no route | VVT oil-control solenoid +12V feed | — | |
| W4 | SP-14V-1 | T2-C1-31 | 0.85 | no route | Ignition 12v In | — | |
| W5 | OEM-4-AG | T2-C1-21 | 0.85 | no route | Constant +12V | — | |
| W6 | OEM-3-A | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W7 | OEM-3-B | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W8 | OEM-4-A | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W9 | SP-GND-1 | T2-C1-13 | 0.85 | no route | Power Ground 1 | — | |
| W10 | SP-GND-1 | T2-C1-14 | 0.85 | no route | Power Ground 2 | — | |
| W11 | OEM-4-O | SP-0V-1 | 0.5 | no route | Signal ground | — | |
| W12 | SP-0V-1 | T2-C1-28 | 0.5 | no route | Sensor Ground | — | |
| W13 | SP-0V-1 | T2-C1-29 | 0.5 | no route | Sensor Ground | — | |
| W14 | OEM-4-L | T2-C1-27 | 0.5 | no route | +5V sensor supply | — | |
| W15 | OEM-3-Y | T2-C1-19 | 0.5 | no route | Crank position (CKP) | — | |
| W16 | OEM-3-V | T2-C1-12 | 0.5 | no route | Cam position (CMP) | — | |
| W17 | OEM-3-F | T2-C1-3 | 0.5 | no route | Ignition 1 (coils 1+4, wasted spark) | — | |
| W18 | OEM-3-I | T2-C1-6 | 0.5 | no route | Ignition 2 (coils 2+3, wasted spark) | — | |
| W19 | OEM-2-A | T2-C1-8 | 0.5 | no route | Injector 1 | — | |
| W20 | OEM-2-D | T2-C1-9 | 0.5 | no route | Injector 2 | — | |
| W21 | OEM-2-G | T2-C1-8 | 0.5 | no route | Injector 3 | — | |
| W22 | OEM-2-J | T2-C1-9 | 0.5 | no route | Injector 4 | — | |
| W23 | OEM-4-X | T2-C1-20 | 0.5 | no route | Mass air flow (MAF) | — | |
| W24 | OEM-4-V | T2-C1-22 | 0.5 | no route | Throttle position (TPS) | — | |
| W25 | OEM-4-P | T2-C1-24 | 0.5 | no route | Coolant temperature (ECT) | — | |
| W26 | OEM-2-B | T2-C1-1 | 0.5 | no route | Cooling fan relay | — | |
| W27 | OEM-2-C | T2-C1-10 | 0.5 | no route | Condenser fan relay | — | |
| W28 | OEM-2-K | T2-C1-18 | 0.5 | no route | A/C clutch relay | — | |
| W29 | OEM-2-M | T2-C1-26 | 0.5 | no route | Fuel pump relay | — | |
| W30 | OEM-3-H | T2-C1-15 | 0.5 | no route | Main relay | — | |
| W31 | OEM-4-AE | T2-C1-23 | 0.5 | no route | Pressure sensor (Mazda: EGR boost sensor) | — | |
| W32 | OEM-4-AA | T2-C1-25 | 0.5 | no route | Rear O2 signal | — | |
| W33 | OEM-4-W | T2-C1-33 | 0.5 | no route | Front O2 signal | — | |
| W34 | OEM-4-N | T2-C1-32 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W35 | OEM-4-AD | T2-C1-34 | 0.5 | no route | Fuel level | — | |
| W36 | OEM-3-T | T2-C1-11 | 0.5 | no route | Vehicle speed | — | |
| W37 | OEM-3-S | T2-C1-30 | 0.5 | no route | Immobiliser | — |
Bill of materials
| Category | Part number | Manufacturer | Description | Qty | Unit |
|---|---|---|---|---|---|
| connector | 4-1437290-0 | TE | Superseal 1.0 34-way plug, Key 1 | 1.000 | ea |
| terminal | 3-1447221-4 | TE | Superseal 1.0 socket terminal, 20 AWG (0.5 sq mm) | 28.000 | ea |
ECU setup sheet
| Role | Engine ref | Engine signal | Sensor | ECU point | ECU function | ECU class | Setup flag |
|---|---|---|---|---|---|---|---|
| No configured channels. | |||||||
Findings
Open (5)
| Severity | Code | Subject | Message |
|---|---|---|---|
| error | NET_MERGED | OEM-2-A + OEM-2-G + T2-C1-8 | 2 different OEM functions share one net: OEM-2-A Injector 1; OEM-2-G Injector 3 |
| error | NET_MERGED | OEM-2-D + OEM-2-J + T2-C1-9 | 2 different OEM functions share one net: OEM-2-D Injector 2; OEM-2-J Injector 4 |
| warn | LOAD_UNKNOWN | T2-C1-15 | T2-C1-15 "Lambda Heater Negative" drives OEM-3-H Main relay (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | NET_FAMILY | OEM-3-V ↔ T2-C1-12 | OEM-3-V "Cam position (CMP)" [trigger_in] is wired to T2-C1-12 "Wheel 1" [digital_in]. Hall-type cam/speed signals can use a digital input if it handles the frequency; VR signals cannot. |
| info | UNMAPPED | OEM | 31 optional OEM pins are not mapped: OEM-2-E EGR valve; OEM-2-F EGR valve; OEM-2-H EGR valve; OEM-2-I EGR valve; OEM-2-N VTCS solenoid (intake butterflies); OEM-2-O Fuel pump relay (non-immobiliser); OEM-2-Q ISC valve low side; OEM-2-R Malfunction indicator lamp (MIL); OEM-3-C Purge solenoid valve; OEM-3-D EGR boost solenoid; OEM-3-J Front O2 heater; OEM-3-K EVAP leak detection pump; OEM-3-M Alternator control; OEM-3-O Tachometer output; OEM-3-P Rear O2 heater; OEM-3-Q Data link connector (K-line); OEM-3-U Charge lamp; OEM-4-AC TCM (automatic only); OEM-4-AH EVAP leak detection pump solenoid valve; OEM-4-B Brake switch; OEM-4-C Power steering pressure switch; OEM-4-E Diagnostic (DLC TEN) (NA); OEM-4-F A/C request; OEM-4-H Neutral switch; OEM-4-I Clutch switch; OEM-4-J VTCS vacuum switch; OEM-4-M Knock sensor; OEM-4-R VVT oil-control solenoid (low-side control); OEM-4-S Ignition switch (IG1) sense; OEM-4-T Generator output voltage (terminal P); OEM-4-Z TCM (automatic only) |
Accepted (0)
| Code | Subject | Reason | By |
|---|
Notes
Fit check: unconfirmed. Confirm these before building: - Trigger pattern for Mazda BP-Z3 not found in the ECU's docs (NB2 VVT not named.) - No knock input; the stock knock sensor would be unused - Only 2 ignition outputs for 4 cylinders: wasted spark (pair coils per firing order) - Only 2 injector outputs for 4 injectors: batch / semi-sequential injection 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-4 M: Knock sensor: no free knock input on DTAFast T2 - OEM-4 S: Ignition switch (IG1) sense: key-on 12 V sense — optional in a swap (the main relay is energized from keyed 12 V, not from this pin); DTAFast T2 has no dedicated key-on input - OEM-2 O: Fuel pump relay (non-immobiliser): no free relay_control/low_side/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-3 J: Front O2 heater: no free heater_low_side/low_side/relay_control/ls_hs/injector on DTAFast T2 - OEM-3 P: Rear O2 heater: no free heater_low_side/low_side/relay_control/ls_hs/injector on DTAFast T2 - OEM-2 Q: ISC valve low side: no free low_side/relay_control/heater_low_side/ls_hs/injector rated ≥ 1.0 A on DTAFast T2 - OEM-2 E: EGR valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-2 F: EGR valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-2 H: EGR valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-2 I: EGR valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-2 N: VTCS solenoid (intake butterflies): no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-2 R: Malfunction indicator lamp (MIL): no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-3 C: Purge solenoid valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-3 K: EVAP leak detection pump: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-3 M: Alternator control: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-3 U: Charge lamp: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-4 AH: EVAP leak detection pump solenoid valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-4 R: VVT oil-control solenoid (low-side control): no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T2 - OEM-3 O: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on DTAFast T2 - OEM-4 B: Brake switch: no free switch_in/frequency_in/analog_0_5 on DTAFast T2 - OEM-4 C: Power steering pressure switch: no free switch_in/frequency_in/analog_0_5 on DTAFast T2 - OEM-4 F: A/C request: no free switch_in/frequency_in/analog_0_5 on DTAFast T2 - OEM-4 H: Neutral switch: no free switch_in/frequency_in/analog_0_5 on DTAFast T2 - OEM-4 I: Clutch switch: no free switch_in/frequency_in/analog_0_5 on DTAFast T2 - OEM-4 J: VTCS vacuum switch: no free switch_in/frequency_in/analog_0_5 on DTAFast T2 - OEM-3 Q: Data link connector (K-line): no free k_line on DTAFast T2 - OEM-4 E: Diagnostic (DLC TEN) (NA): no free k_line on DTAFast T2 - OEM-3 D: EGR boost solenoid: not classified in the library; wire by hand - OEM-4 AC: TCM (automatic only): not classified in the library; wire by hand - OEM-4 T: Generator output voltage (terminal P): not classified in the library; wire by hand - OEM-4 Z: TCM (automatic only): not classified in the library; wire by hand
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | oem_manual | 2005 Mazda MX-5 Miata Engine Performance Control System (PCM terminal voltage reference, BP and BP WITH TC) | https://trull.org/alex/pubmirror/www.mellens.net/mazda/Mazda-Miata-2005/engine_control_system.pdf | — | — | — |
| 4 | vendor_doc | Adaptronic eSel039 Select Plugin ECU for Mazda MX5 / Miata NB8B/C (OEM ECU pinout) | https://www.miataturbo.net/attachments/ecus-tuning-54/04-msm-ecu-pinout-104032/nb8bc_oem_ecu_pinouts-224948d1602912806 | — | — | — |
| 4 | vendor_doc | DTAFast T2 ECU wiring diagram | https://cdn.shopify.com/s/files/1/0848/7508/4108/files/T2_Wiring-Diagram.pdf?v=1728571340 | — | — | — |
| 4 | vendor_doc | Link G4X MX5NB2X install manual (NB2 2001-05) | https://linkecu.com/documentation/MX5XNB2.pdf | archive | 2026-10-05 | 741efdd9f2c8 |
| 4 | oem_manual | Mazda MX-5 NB2 (2003) wiring diagram — engine / starting / charging | https://web.archive.org/web/20191104195207/http://mellens.net/mazda/mazda_miata_extra_manual/2003_wiring.pdf | — | 2026-10-05 | 5ee0777f12c1 |
| 2 | expert_report | Justin Barrera — Miata NA/NB wiring corrections | — | — | — | — |