MX-5 Miata NB2 2001-05 (BP-Z3, VVT; excludes Mazdaspeed) → ECUMASTER EMU Black (auto)
MX-5 Miata NB2 2001-05 (BP-Z3, VVT; excludes Mazdaspeed) — ECUMASTER — EMU Black
Drawn by Michael Gnankou · Rev 0 · proposal · 2026-10-09
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 | proposal · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | none |
| Size of the job | 52 wires · 8 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-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 | EMUBLACK-Black-13 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | OEM-3-A | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-3-B | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-4-A | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | SP-GND-1 | EMUBLACK-Black-27 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-GND-1 | EMUBLACK-Black-28 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-GND-1 | EMUBLACK-Grey-17 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | SP-GND-1 | EMUBLACK-Grey-24 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-4-O | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | SP-0V-1 | EMUBLACK-Black-29 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | SP-0V-1 | EMUBLACK-Black-38 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | SP-0V-1 | EMUBLACK-Black-39 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | OEM-4-L | EMUBLACK-Black-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-3-Y | EMUBLACK-Black-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-3-V | EMUBLACK-Black-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-4-M | EMUBLACK-Black-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-3-F | EMUBLACK-Grey-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-3-I | EMUBLACK-Grey-16 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-2-A | EMUBLACK-Grey-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-2-D | EMUBLACK-Grey-15 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-2-G | EMUBLACK-Grey-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-2-J | EMUBLACK-Grey-6 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-2-B | EMUBLACK-Grey-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-2-C | EMUBLACK-Grey-13 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-2-K | EMUBLACK-Grey-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-2-M | EMUBLACK-Grey-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-3-H | EMUBLACK-Grey-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-3-J | EMUBLACK-Grey-19 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-3-P | EMUBLACK-Grey-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-2-Q | EMUBLACK-Grey-14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-2-E | EMUBLACK-Grey-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-2-F | EMUBLACK-Grey-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-2-H | EMUBLACK-Grey-2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-2-I | EMUBLACK-Grey-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-2-N | EMUBLACK-Grey-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-4-X | EMUBLACK-Black-31 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-4-AE | EMUBLACK-Black-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-4-V | EMUBLACK-Black-18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W42 | OEM-4-AA | EMUBLACK-Black-17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W43 | OEM-4-W | EMUBLACK-Black-30 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W44 | OEM-4-P | EMUBLACK-Black-32 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W45 | OEM-4-N | EMUBLACK-Black-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W46 | OEM-4-AD | EMUBLACK-Black-9 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W47 | OEM-3-T | EMUBLACK-Black-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W48 | OEM-3-S | EMUBLACK-Black-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W49 | OEM-4-B | EMUBLACK-Black-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W50 | OEM-4-C | EMUBLACK-Black-36 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W51 | OEM-4-F | EMUBLACK-Black-35 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W52 | OEM-4-H | EMUBLACK-Black-37 | 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 | EMUBLACK-Black-13 | EMUBLACK-Black-27 | open (OL) | +12 V supply must not touch power ground | |
| 2 | EMUBLACK-Black-13 | EMUBLACK-Black-29 | open (OL) | +12 V supply must not touch sensor ground | |
| 3 | EMUBLACK-Black-26 | EMUBLACK-Black-29 | open (OL) | 5 V sensor reference must not touch sensor ground | |
| 4 | EMUBLACK-Black-13 | EMUBLACK-Black-26 | open (OL) | +12 V supply must not touch 5 V sensor reference | |
| 5 | EMUBLACK-Black-27 | EMUBLACK-Black-26 | open (OL) | power ground 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
EMUBLACK-Black
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Ignition coil #5 | — | — | — | — | — | — | — | — |
| 10 | Switch #1 In | — | W48 | — | 0.5 | OEM-3-S | — | — | — |
| 11 | RS232 TXD | — | — | — | — | — | — | — | — |
| 12 | CAN H | — | — | — | — | — | — | — | — |
| 13 | Battery +12V | — | W4 | — | 0.85 | SP-14V-1 | — | — | — |
| 14 | Ignition coil #4 | — | — | — | — | — | — | — | — |
| 15 | EGT in #2 | — | — | — | — | — | — | — | — |
| 16 | Knock Sensor in #2 | — | — | — | — | — | — | — | — |
| 17 | Analog In #3 | — | W42 | — | 0.5 | OEM-4-AA | — | — | — |
| 18 | TPS In | — | W41 | — | 0.5 | OEM-4-V | — | — | — |
| 19 | WBO Ip | — | — | — | — | — | — | — | — |
| 2 | EGT in #1 | — | — | — | — | — | — | — | — |
| 20 | VSS In | — | W47 | — | 0.5 | OEM-3-T | — | — | — |
| 21 | Camsync In #1 | — | W18 | — | 0.5 | OEM-3-V | — | — | — |
| 22 | WBO Rcal | — | — | — | — | — | — | — | — |
| 23 | Switch #2 In | — | W49 | — | 0.5 | OEM-4-B | — | — | — |
| 24 | RS232 RXD | — | — | — | — | — | — | — | — |
| 25 | CAN L | — | — | — | — | — | — | — | — |
| 26 | +5V supply | — | W16 | — | 0.5 | OEM-4-L | — | — | — |
| 27 | Power Ground | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| 28 | Ecu Ground | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
| 29 | Sensor Ground | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 3 | Knock Sensor in #1 | — | W19 | — | 0.5 | OEM-4-M | — | — | — |
| 30 | Analog In #4 | — | W43 | — | 0.5 | OEM-4-W | — | — | — |
| 31 | Analog In #1 | — | W39 | — | 0.5 | OEM-4-X | — | — | — |
| 32 | IAT In | — | W44 | — | 0.5 | OEM-4-P | — | — | — |
| 33 | WBO VGND | — | — | — | — | — | — | — | — |
| 34 | +5V supply | — | — | — | — | — | — | — | — |
| 35 | Analog In #5 | — | W51 | — | 0.5 | OEM-4-F | — | — | — |
| 36 | Switch #3 In | — | W50 | — | 0.5 | OEM-4-C | — | — | — |
| 37 | Analog In #6 | — | W52 | — | 0.5 | OEM-4-H | — | — | — |
| 38 | Sensor Ground | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| 39 | Sensor Ground | — | W15 | — | 0.5 | SP-0V-1 | — | — | — |
| 4 | Analog In #2 | — | W40 | — | 0.5 | OEM-4-AE | — | — | — |
| 5 | CLT In | — | W45 | — | 0.5 | OEM-4-N | — | — | — |
| 6 | WBO Vs | — | — | — | — | — | — | — | — |
| 7 | Camsync In #2 | — | — | — | — | — | — | — | — |
| 8 | Primary trigger | — | W17 | — | 0.5 | OEM-3-Y | — | — | — |
| 9 | Flex Fuel In | — | W46 | — | 0.5 | OEM-4-AD | — | — | — |
EMUBLACK-Grey
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Ignition coil #6 | — | — | — | — | — | — | — | — |
| 10 | H-Bridge #1 Winding B | — | W35 | — | 0.5 | OEM-2-F | — | — | — |
| 11 | H-Bridge #2 Winding B | — | W37 | — | 0.5 | OEM-2-I | — | — | — |
| 12 | AUX 5 | — | W30 | — | 0.5 | OEM-3-H | — | — | — |
| 13 | AUX 2 / Injector #8 | — | W27 | — | 0.5 | OEM-2-C | — | — | — |
| 14 | Injector #5 | — | W33 | — | 0.5 | OEM-2-Q | — | — | — |
| 15 | Injector #2 | — | W23 | — | 0.5 | OEM-2-D | — | — | — |
| 16 | Ignition coil #2 | — | W21 | — | 0.5 | OEM-3-I | — | — | — |
| 17 | Power Ground | — | W10 | — | 0.85 | SP-GND-1 | — | — | — |
| 18 | Ignition +12V | — | — | — | — | — | — | — | — |
| 19 | WBO Heater | — | W31 | — | 0.5 | OEM-3-J | — | — | — |
| 2 | H-Bridge #1 Winding A | — | W36 | — | 0.5 | OEM-2-H | — | — | — |
| 20 | AUX 4 / Tacho | — | W29 | — | 0.5 | OEM-2-M | — | — | — |
| 21 | AUX 1 / Injector #7 | — | W26 | — | 0.5 | OEM-2-B | — | — | — |
| 22 | Injector #6 | — | W34 | — | 0.5 | OEM-2-E | — | — | — |
| 23 | Injector #3 | — | W24 | — | 0.5 | OEM-2-G | — | — | — |
| 24 | Power Ground | — | W11 | — | 0.85 | SP-GND-1 | — | — | — |
| 3 | H-Bridge #2 Winding A | — | W38 | — | 0.5 | OEM-2-N | — | — | — |
| 4 | AUX 6 | — | W32 | — | 0.5 | OEM-3-P | — | — | — |
| 5 | AUX 3 | — | W28 | — | 0.5 | OEM-2-K | — | — | — |
| 6 | Injector #4 | — | W25 | — | 0.5 | OEM-2-J | — | — | — |
| 7 | Injector #1 | — | W22 | — | 0.5 | OEM-2-A | — | — | — |
| 8 | Ignition coil #1 | — | W20 | — | 0.5 | OEM-3-F | — | — | — |
| 9 | Ignition coil #3 | — | — | — | — | — | — | — | — |
OEM-2
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Injector 1 | — | W22 | — | 0.5 | EMUBLACK-Grey-7 | — | — | — |
| B | Cooling fan relay | — | W26 | — | 0.5 | EMUBLACK-Grey-21 | — | — | — |
| C | Condenser fan relay | — | W27 | — | 0.5 | EMUBLACK-Grey-13 | — | — | — |
| D | Injector 2 | — | W23 | — | 0.5 | EMUBLACK-Grey-15 | — | — | — |
| E | EGR valve | — | W34 | — | 0.5 | EMUBLACK-Grey-22 | — | — | — |
| F | EGR valve | — | W35 | — | 0.5 | EMUBLACK-Grey-10 | — | — | — |
| G | Injector 3 | — | W24 | — | 0.5 | EMUBLACK-Grey-23 | — | — | — |
| H | EGR valve | — | W36 | — | 0.5 | EMUBLACK-Grey-2 | — | — | — |
| I | EGR valve | — | W37 | — | 0.5 | EMUBLACK-Grey-11 | — | — | — |
| J | Injector 4 | — | W25 | — | 0.5 | EMUBLACK-Grey-6 | — | — | — |
| K | A/C clutch relay | — | W28 | — | 0.5 | EMUBLACK-Grey-5 | — | — | — |
| M | Fuel pump relay | — | W29 | — | 0.5 | EMUBLACK-Grey-20 | — | — | — |
| N | VTCS solenoid (intake butterflies) | — | W38 | — | 0.5 | EMUBLACK-Grey-3 | — | — | — |
| P | ISC valve +14V feed | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| Q | ISC valve low side | — | W33 | — | 0.5 | EMUBLACK-Grey-14 | — | — | — |
| R | Malfunction indicator lamp (MIL) | — | — | — | — | — | — | — | — |
OEM-3
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Power ground | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| B | Power ground | — | W6 | — | 0.85 | SP-GND-1 | — | — | — |
| D | EGR boost solenoid | — | — | — | — | — | — | — | — |
| E | Charcoal canister purge | — | — | — | — | — | — | — | — |
| F | Ignition 1 (coils 1+4, wasted spark) | — | W20 | — | 0.5 | EMUBLACK-Grey-8 | — | — | — |
| H | Main relay | — | W30 | — | 0.5 | EMUBLACK-Grey-12 | — | — | — |
| I | Ignition 2 (coils 2+3, wasted spark) | — | W21 | — | 0.5 | EMUBLACK-Grey-16 | — | — | — |
| J | Front O2 heater | — | W31 | — | 0.5 | EMUBLACK-Grey-19 | — | — | — |
| M | Alternator control | — | — | — | — | — | — | — | — |
| O | Tachometer output | — | — | — | — | — | — | — | — |
| P | Rear O2 heater | — | W32 | — | 0.5 | EMUBLACK-Grey-4 | — | — | — |
| S | Immobiliser | — | W48 | — | 0.5 | EMUBLACK-Black-10 | — | — | — |
| T | Vehicle speed | — | W47 | — | 0.5 | EMUBLACK-Black-20 | — | — | — |
| U | Charge lamp | — | — | — | — | — | — | — | — |
| V | Cam position (CMP) | — | W18 | — | 0.5 | EMUBLACK-Black-21 | — | — | — |
| Y | Crank position (CKP) | — | W17 | — | 0.5 | EMUBLACK-Black-8 | — | — | — |
OEM-4
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Power ground | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| AA | Rear O2 signal | — | W42 | — | 0.5 | EMUBLACK-Black-17 | — | — | — |
| AD | Fuel level | — | W46 | — | 0.5 | EMUBLACK-Black-9 | — | — | — |
| AE | Pressure sensor (Mazda: EGR boost sensor) | — | W40 | — | 0.5 | EMUBLACK-Black-4 | — | — | — |
| AF | ECU power +14V (main relay) | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| AG | Constant +12V | — | — | — | — | — | — | — | — |
| B | Brake switch | — | W49 | — | 0.5 | EMUBLACK-Black-23 | — | — | — |
| C | Power steering pressure switch | — | W50 | — | 0.5 | EMUBLACK-Black-36 | — | — | — |
| D | VVT oil-control solenoid +12V feed | — | W3 | — | 0.85 | SP-14V-1 | — | — | — |
| F | A/C request | — | W51 | — | 0.5 | EMUBLACK-Black-35 | — | — | — |
| H | Neutral switch | — | W52 | — | 0.5 | EMUBLACK-Black-37 | — | — | — |
| I | Clutch switch | — | — | — | — | — | — | — | — |
| J | VTCS vacuum switch | — | — | — | — | — | — | — | — |
| L | +5V sensor supply | — | W16 | — | 0.5 | EMUBLACK-Black-26 | — | — | — |
| M | Knock sensor | — | W19 | — | 0.5 | EMUBLACK-Black-3 | — | — | — |
| N | Intake air temperature (IAT) | — | W45 | — | 0.5 | EMUBLACK-Black-5 | — | — | — |
| O | Signal ground | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| P | Coolant temperature (ECT) | — | W44 | — | 0.5 | EMUBLACK-Black-32 | — | — | — |
| R | VVT oil-control solenoid (low-side control) | — | — | — | — | — | — | — | — |
| V | Throttle position (TPS) | — | W41 | — | 0.5 | EMUBLACK-Black-18 | — | — | — |
| W | Front O2 signal | — | W43 | — | 0.5 | EMUBLACK-Black-30 | — | — | — |
| X | Mass air flow (MAF) | — | W39 | — | 0.5 | EMUBLACK-Black-31 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W12 | — | 0.5 | OEM-4-O | — | — | — |
| 1 | — | — | W13 | — | 0.5 | EMUBLACK-Black-29 | — | — | — |
| 1 | — | — | W14 | — | 0.5 | EMUBLACK-Black-38 | — | — | — |
| 1 | — | — | W15 | — | 0.5 | EMUBLACK-Black-39 | — | — | — |
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 | EMUBLACK-Black-13 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W5 | — | 0.85 | OEM-3-A | — | — | — |
| 1 | — | — | W6 | — | 0.85 | OEM-3-B | — | — | — |
| 1 | — | — | W7 | — | 0.85 | OEM-4-A | — | — | — |
| 1 | — | — | W8 | — | 0.85 | EMUBLACK-Black-27 | — | — | — |
| 1 | — | — | W9 | — | 0.85 | EMUBLACK-Black-28 | — | — | — |
| 1 | — | — | W10 | — | 0.85 | EMUBLACK-Grey-17 | — | — | — |
| 1 | — | — | W11 | — | 0.85 | EMUBLACK-Grey-24 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-2-A | Injector 1 | injector_out | EMUBLACK-Grey-7 | Injector #1 | injector_out | single_source | |
| OEM-2-B | Cooling fan relay | low_side_out | EMUBLACK-Grey-21 | AUX 1 / Injector #7 | low_side_out | single_source | |
| OEM-2-C | Condenser fan relay | low_side_out | EMUBLACK-Grey-13 | AUX 2 / Injector #8 | low_side_out | single_source | |
| OEM-2-D | Injector 2 | injector_out | EMUBLACK-Grey-15 | Injector #2 | injector_out | single_source | |
| OEM-2-E | EGR valve | low_side_out | EMUBLACK-Grey-22 | Injector #6 | injector_out | single_source | |
| OEM-2-F | EGR valve | low_side_out | EMUBLACK-Grey-10 | H-Bridge #1 Winding B | hbridge_out | single_source | |
| OEM-2-G | Injector 3 | injector_out | EMUBLACK-Grey-23 | Injector #3 | injector_out | single_source | |
| OEM-2-H | EGR valve | low_side_out | EMUBLACK-Grey-2 | H-Bridge #1 Winding A | hbridge_out | single_source | |
| OEM-2-I | EGR valve | low_side_out | EMUBLACK-Grey-11 | H-Bridge #2 Winding B | hbridge_out | single_source | |
| OEM-2-J | Injector 4 | injector_out | EMUBLACK-Grey-6 | Injector #4 | injector_out | single_source | |
| OEM-2-K | A/C clutch relay | low_side_out | EMUBLACK-Grey-5 | AUX 3 | low_side_out | single_source | |
| OEM-2-M | Fuel pump relay | low_side_out | EMUBLACK-Grey-20 | AUX 4 / Tacho | low_side_out | single_source | |
| OEM-2-N | VTCS solenoid (intake butterflies) | low_side_out | EMUBLACK-Grey-3 | H-Bridge #2 Winding A | hbridge_out | single_source | |
| OEM-2-P | ISC valve +14V feed | power_in | EMUBLACK-Black-13 | Battery +12V | power_in | single_source | |
| OEM-2-Q | ISC valve low side | low_side_out | EMUBLACK-Grey-14 | Injector #5 | injector_out | single_source | |
| OEM-2-R | Malfunction indicator lamp (MIL) | low_side_out | — | — | — | single_source | |
| OEM-3-A | Power ground | ground | EMUBLACK-Black-27 + EMUBLACK-Black-28 + EMUBLACK-Grey-17 + EMUBLACK-Grey-24 | Power Ground + Ecu Ground + Power Ground + Power Ground | ground | single_source | |
| OEM-3-B | Power ground | ground | EMUBLACK-Black-27 + EMUBLACK-Black-28 + EMUBLACK-Grey-17 + EMUBLACK-Grey-24 | Power Ground + Ecu Ground + Power Ground + Power Ground | ground | single_source | |
| OEM-3-D | EGR boost solenoid | — | — | — | — | single_source | |
| OEM-3-E | Charcoal canister purge | low_side_out | — | — | — | single_source | |
| OEM-3-F | Ignition 1 (coils 1+4, wasted spark) | ignition_out | EMUBLACK-Grey-8 | Ignition coil #1 | ignition_out | single_source | |
| OEM-3-H | Main relay | low_side_out | EMUBLACK-Grey-12 | AUX 5 | low_side_out | single_source | |
| OEM-3-I | Ignition 2 (coils 2+3, wasted spark) | ignition_out | EMUBLACK-Grey-16 | Ignition coil #2 | ignition_out | single_source | |
| OEM-3-J | Front O2 heater | low_side_out | EMUBLACK-Grey-19 | WBO Heater | low_side_out | single_source | |
| OEM-3-M | Alternator control | low_side_out | — | — | — | single_source | |
| OEM-3-O | Tachometer output | tacho_out | — | — | — | single_source | |
| OEM-3-P | Rear O2 heater | low_side_out | EMUBLACK-Grey-4 | AUX 6 | low_side_out | single_source | |
| OEM-3-S | Immobiliser | digital_in | EMUBLACK-Black-10 | Switch #1 In | digital_in | single_source | |
| OEM-3-T | Vehicle speed | digital_in | EMUBLACK-Black-20 | VSS In | digital_in | single_source | |
| OEM-3-U | Charge lamp | low_side_out | — | — | — | single_source | |
| OEM-3-V | Cam position (CMP) | trigger_in | EMUBLACK-Black-21 | Camsync In #1 | trigger_in | single_source | |
| OEM-3-Y | Crank position (CKP) | trigger_in | EMUBLACK-Black-8 | Primary trigger | trigger_in | single_source | |
| OEM-4-A | Power ground | ground | EMUBLACK-Black-27 + EMUBLACK-Black-28 + EMUBLACK-Grey-17 + EMUBLACK-Grey-24 | Power Ground + Ecu Ground + Power Ground + Power Ground | ground | single_source | |
| OEM-4-AA | Rear O2 signal | lambda_nb_in | EMUBLACK-Black-17 | Analog In #3 | analog_in | single_source | |
| OEM-4-AD | Fuel level | analog_in | EMUBLACK-Black-9 | Flex Fuel In | analog_in | single_source | |
| OEM-4-AE | Pressure sensor (Mazda: EGR boost sensor) | analog_in | EMUBLACK-Black-4 | Analog In #2 | analog_in | corroborated | |
| OEM-4-AF | ECU power +14V (main relay) | power_in | EMUBLACK-Black-13 | Battery +12V | power_in | single_source | |
| OEM-4-AG | Constant +12V | power_in | — | — | — | single_source | |
| OEM-4-B | Brake switch | digital_in | EMUBLACK-Black-23 | Switch #2 In | digital_in | single_source | |
| OEM-4-C | Power steering pressure switch | digital_in | EMUBLACK-Black-36 | Switch #3 In | digital_in | single_source | |
| OEM-4-D | VVT oil-control solenoid +12V feed | power_in | EMUBLACK-Black-13 | Battery +12V | power_in | Y | single_source |
| OEM-4-F | A/C request | digital_in | EMUBLACK-Black-35 | Analog In #5 | analog_in | single_source | |
| OEM-4-H | Neutral switch | digital_in | EMUBLACK-Black-37 | Analog In #6 | analog_in | single_source | |
| OEM-4-I | Clutch switch | digital_in | — | — | — | single_source | |
| OEM-4-J | VTCS vacuum switch | digital_in | — | — | — | single_source | |
| OEM-4-L | +5V sensor supply | vref | EMUBLACK-Black-26 | +5V supply | vref | single_source | |
| OEM-4-M | Knock sensor | knock_in | EMUBLACK-Black-3 | Knock Sensor in #1 | knock_in | single_source | |
| OEM-4-N | Intake air temperature (IAT) | temp_in | EMUBLACK-Black-5 | CLT In | temp_in | single_source | |
| OEM-4-O | Signal ground | sensor_ground | EMUBLACK-Black-29 + EMUBLACK-Black-38 + EMUBLACK-Black-39 | Sensor Ground + Sensor Ground + Sensor Ground | sensor_ground | single_source | |
| OEM-4-P | Coolant temperature (ECT) | temp_in | EMUBLACK-Black-32 | IAT In | temp_in | single_source | |
| OEM-4-R | VVT oil-control solenoid (low-side control) | low_side_out | — | — | — | VY | corroborated |
| OEM-4-V | Throttle position (TPS) | analog_in | EMUBLACK-Black-18 | TPS In | analog_in | single_source | |
| OEM-4-W | Front O2 signal | lambda_nb_in | EMUBLACK-Black-30 | Analog In #4 | analog_in | single_source | |
| OEM-4-X | Mass air flow (MAF) | analog_in | EMUBLACK-Black-31 | Analog In #1 | analog_in | 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 | EMUBLACK-Black-13 | 0.85 | no route | Battery +12V | — | |
| W5 | OEM-3-A | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W6 | OEM-3-B | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W7 | OEM-4-A | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W8 | SP-GND-1 | EMUBLACK-Black-27 | 0.85 | no route | Power Ground | — | |
| W9 | SP-GND-1 | EMUBLACK-Black-28 | 0.85 | no route | Ecu Ground | — | |
| W10 | SP-GND-1 | EMUBLACK-Grey-17 | 0.85 | no route | Power Ground | — | |
| W11 | SP-GND-1 | EMUBLACK-Grey-24 | 0.85 | no route | Power Ground | — | |
| W12 | OEM-4-O | SP-0V-1 | 0.5 | no route | Signal ground | — | |
| W13 | SP-0V-1 | EMUBLACK-Black-29 | 0.5 | no route | Sensor Ground | — | |
| W14 | SP-0V-1 | EMUBLACK-Black-38 | 0.5 | no route | Sensor Ground | — | |
| W15 | SP-0V-1 | EMUBLACK-Black-39 | 0.5 | no route | Sensor Ground | — | |
| W16 | OEM-4-L | EMUBLACK-Black-26 | 0.5 | no route | +5V sensor supply | — | |
| W17 | OEM-3-Y | EMUBLACK-Black-8 | 0.5 | no route | Crank position (CKP) | — | |
| W18 | OEM-3-V | EMUBLACK-Black-21 | 0.5 | no route | Cam position (CMP) | — | |
| W19 | OEM-4-M | EMUBLACK-Black-3 | 0.5 | no route | Knock sensor | — | |
| W20 | OEM-3-F | EMUBLACK-Grey-8 | 0.5 | no route | Ignition 1 (coils 1+4, wasted spark) | — | |
| W21 | OEM-3-I | EMUBLACK-Grey-16 | 0.5 | no route | Ignition 2 (coils 2+3, wasted spark) | — | |
| W22 | OEM-2-A | EMUBLACK-Grey-7 | 0.5 | no route | Injector 1 | — | |
| W23 | OEM-2-D | EMUBLACK-Grey-15 | 0.5 | no route | Injector 2 | — | |
| W24 | OEM-2-G | EMUBLACK-Grey-23 | 0.5 | no route | Injector 3 | — | |
| W25 | OEM-2-J | EMUBLACK-Grey-6 | 0.5 | no route | Injector 4 | — | |
| W26 | OEM-2-B | EMUBLACK-Grey-21 | 0.5 | no route | Cooling fan relay | — | |
| W27 | OEM-2-C | EMUBLACK-Grey-13 | 0.5 | no route | Condenser fan relay | — | |
| W28 | OEM-2-K | EMUBLACK-Grey-5 | 0.5 | no route | A/C clutch relay | — | |
| W29 | OEM-2-M | EMUBLACK-Grey-20 | 0.5 | no route | Fuel pump relay | — | |
| W30 | OEM-3-H | EMUBLACK-Grey-12 | 0.5 | no route | Main relay | — | |
| W31 | OEM-3-J | EMUBLACK-Grey-19 | 0.5 | no route | Front O2 heater | — | |
| W32 | OEM-3-P | EMUBLACK-Grey-4 | 0.5 | no route | Rear O2 heater | — | |
| W33 | OEM-2-Q | EMUBLACK-Grey-14 | 0.5 | no route | ISC valve low side | — | |
| W34 | OEM-2-E | EMUBLACK-Grey-22 | 0.5 | no route | EGR valve | — | |
| W35 | OEM-2-F | EMUBLACK-Grey-10 | 0.5 | no route | EGR valve | — | |
| W36 | OEM-2-H | EMUBLACK-Grey-2 | 0.5 | no route | EGR valve | — | |
| W37 | OEM-2-I | EMUBLACK-Grey-11 | 0.5 | no route | EGR valve | — | |
| W38 | OEM-2-N | EMUBLACK-Grey-3 | 0.5 | no route | VTCS solenoid (intake butterflies) | — | |
| W39 | OEM-4-X | EMUBLACK-Black-31 | 0.5 | no route | Mass air flow (MAF) | — | |
| W40 | OEM-4-AE | EMUBLACK-Black-4 | 0.5 | no route | Pressure sensor (Mazda: EGR boost sensor) | — | |
| W41 | OEM-4-V | EMUBLACK-Black-18 | 0.5 | no route | Throttle position (TPS) | — | |
| W42 | OEM-4-AA | EMUBLACK-Black-17 | 0.5 | no route | Rear O2 signal | — | |
| W43 | OEM-4-W | EMUBLACK-Black-30 | 0.5 | no route | Front O2 signal | — | |
| W44 | OEM-4-P | EMUBLACK-Black-32 | 0.5 | no route | Coolant temperature (ECT) | — | |
| W45 | OEM-4-N | EMUBLACK-Black-5 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W46 | OEM-4-AD | EMUBLACK-Black-9 | 0.5 | no route | Fuel level | — | |
| W47 | OEM-3-T | EMUBLACK-Black-20 | 0.5 | no route | Vehicle speed | — | |
| W48 | OEM-3-S | EMUBLACK-Black-10 | 0.5 | no route | Immobiliser | — | |
| W49 | OEM-4-B | EMUBLACK-Black-23 | 0.5 | no route | Brake switch | — | |
| W50 | OEM-4-C | EMUBLACK-Black-36 | 0.5 | no route | Power steering pressure switch | — | |
| W51 | OEM-4-F | EMUBLACK-Black-35 | 0.5 | no route | A/C request | — | |
| W52 | OEM-4-H | EMUBLACK-Black-37 | 0.5 | no route | Neutral 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 (9)
| Severity | Code | Subject | Message |
|---|---|---|---|
| warn | NET_FAMILY | OEM-2-F ↔ EMUBLACK-Grey-10 | OEM-2-F "EGR valve" [low_side_out] is wired to EMUBLACK-Grey-10 "H-Bridge #1 Winding B" [hbridge_out]. A half-bridge can act as a low-side switch only if configured that way. |
| warn | NET_FAMILY | OEM-2-H ↔ EMUBLACK-Grey-2 | OEM-2-H "EGR valve" [low_side_out] is wired to EMUBLACK-Grey-2 "H-Bridge #1 Winding A" [hbridge_out]. A half-bridge can act as a low-side switch only if configured that way. |
| warn | NET_FAMILY | OEM-2-I ↔ EMUBLACK-Grey-11 | OEM-2-I "EGR valve" [low_side_out] is wired to EMUBLACK-Grey-11 "H-Bridge #2 Winding B" [hbridge_out]. A half-bridge can act as a low-side switch only if configured that way. |
| warn | NET_FAMILY | OEM-2-N ↔ EMUBLACK-Grey-3 | OEM-2-N "VTCS solenoid (intake butterflies)" [low_side_out] is wired to EMUBLACK-Grey-3 "H-Bridge #2 Winding A" [hbridge_out]. A half-bridge can act as a low-side switch only if configured that way. |
| warn | NET_FAMILY | OEM-4-F ↔ EMUBLACK-Black-35 | OEM-4-F "A/C request" [digital_in] is wired to EMUBLACK-Black-35 "Analog In #5" [analog_in]. Analog and digital on one net. A switch on an analog input works with a pull-up and a threshold; an analog sensor on a digital input loses its value. |
| warn | NET_FAMILY | OEM-4-H ↔ EMUBLACK-Black-37 | OEM-4-H "Neutral switch" [digital_in] is wired to EMUBLACK-Black-37 "Analog In #6" [analog_in]. Analog and digital on one net. A switch on an analog input works with a pull-up and a threshold; an analog sensor on a digital input loses its value. |
| info | NET_FAMILY | OEM-2-E ↔ EMUBLACK-Grey-22 | OEM-2-E "EGR valve" [low_side_out] is wired to EMUBLACK-Grey-22 "Injector #6" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency. |
| info | NET_FAMILY | OEM-2-Q ↔ EMUBLACK-Grey-14 | OEM-2-Q "ISC valve low side" [low_side_out] is wired to EMUBLACK-Grey-14 "Injector #5" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency. |
| info | UNMAPPED | OEM | 9 optional OEM pins are not mapped: OEM-2-R Malfunction indicator lamp (MIL); OEM-3-D EGR boost solenoid; OEM-3-E Charcoal canister purge; OEM-3-M Alternator control; OEM-3-O Tachometer output; OEM-3-U Charge lamp; OEM-4-I Clutch switch; OEM-4-J VTCS vacuum switch; OEM-4-R VVT oil-control solenoid (low-side control) |
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-4-AG | 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 2026-10-09. Review every wire against both manuals before building. Not wired: - OEM-4 AG: Constant +12V: ECUMASTER EMU Black has no battery-constant input; not needed - OEM-2 R: Malfunction indicator lamp (MIL): no free low_side/ls_hs/injector/hbridge on ECUMASTER EMU Black - OEM-3 E: Charcoal canister purge: no free low_side/ls_hs/injector/hbridge on ECUMASTER EMU Black - OEM-3 M: Alternator control: no free low_side/ls_hs/injector/hbridge on ECUMASTER EMU Black - OEM-3 U: Charge lamp: no free low_side/ls_hs/injector/hbridge on ECUMASTER EMU Black - OEM-4 R: VVT oil-control solenoid (low-side control): no free low_side/ls_hs/injector/hbridge on ECUMASTER EMU Black - OEM-3 O: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on ECUMASTER EMU Black - OEM-4 I: Clutch switch: no free switch_in/frequency_in/analog_0_5 on ECUMASTER EMU Black - OEM-4 J: VTCS vacuum switch: no free switch_in/frequency_in/analog_0_5 on ECUMASTER EMU Black - OEM-3 D: EGR boost solenoid: not classified in the library; wire by hand - EMUBLACK-Grey 18: Ignition +12V: not fed (the stock ECU has no ignition-sense pin); feed it from a switched-ignition source
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 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 | ECUMASTER EMU Black — pinout (Black 39-pin / Grey 24-pin) | https://www.ecumaster.com/wp/wp-content/uploads/2020/05/EMU_Black_pinout.pdf | archive | 2026-10-05 | 096b2b4df1bd |
| 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 | — | — | — | — |