MX-5 Miata NA8 1996-97 (BP-ZE, 1.8, OBD-II) → ECUMASTER EMU Black (auto)
MX-5 Miata NA8 1996-97 (BP-ZE, 1.8, OBD-II) — ECUMASTER — EMU Black
Drawn by Michael Gnankou · Rev 0 · proposal · 2026-10-12
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 | 48 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-4-B | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | SP-14V-1 | EMUBLACK-Black-13 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-4-A | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | OEM-4-C | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | OEM-4-D | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-4-K | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | SP-GND-1 | EMUBLACK-Black-27 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | SP-GND-1 | EMUBLACK-Black-28 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-GND-1 | EMUBLACK-Grey-17 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-GND-1 | EMUBLACK-Grey-24 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-3-O | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-4-H | 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-3-I | EMUBLACK-Black-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-4-E | EMUBLACK-Black-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-4-G | EMUBLACK-Black-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-4-F | EMUBLACK-Black-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-4-N | EMUBLACK-Grey-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-4-R | EMUBLACK-Grey-16 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-4-U | EMUBLACK-Grey-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-4-V | EMUBLACK-Grey-15 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-4-W | EMUBLACK-Grey-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-4-X | EMUBLACK-Grey-6 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-3-B | EMUBLACK-Black-31 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-3-F | EMUBLACK-Black-18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-3-G | EMUBLACK-Black-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-1-A | EMUBLACK-Grey-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-1-B | EMUBLACK-Grey-13 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-1-G | EMUBLACK-Grey-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-1-U | EMUBLACK-Grey-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-3-M | EMUBLACK-Grey-19 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-1-E | EMUBLACK-Grey-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-4-J | EMUBLACK-Grey-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-4-O | EMUBLACK-Grey-14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-4-P | EMUBLACK-Grey-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-3-H | EMUBLACK-Black-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-3-N | EMUBLACK-Black-17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-3-C | EMUBLACK-Black-30 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-3-D | EMUBLACK-Black-35 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W42 | OEM-3-K | EMUBLACK-Black-32 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W43 | OEM-3-J | EMUBLACK-Black-37 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W44 | OEM-1-M | EMUBLACK-Black-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W45 | OEM-1-C | EMUBLACK-Black-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W46 | OEM-1-K | EMUBLACK-Black-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W47 | OEM-1-L | EMUBLACK-Black-36 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W48 | OEM-1-Q | EMUBLACK-Black-9 | 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 | EMUBLACK-Black-26 | EMUBLACK-Black-27 | open (OL) | 5 V sensor reference must not touch power ground | |
| 2 | EMUBLACK-Black-26 | EMUBLACK-Black-29 | open (OL) | 5 V sensor reference must not touch sensor ground | |
| 3 | EMUBLACK-Black-26 | EMUBLACK-Black-13 | open (OL) | 5 V sensor reference must not touch +12 V supply | |
| 4 | EMUBLACK-Black-27 | EMUBLACK-Black-13 | open (OL) | power ground must not touch +12 V supply | |
| 5 | EMUBLACK-Black-29 | EMUBLACK-Black-13 | open (OL) | sensor ground must not touch +12 V supply |
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 | — | W45 | — | 0.5 | OEM-1-C | — | — | — |
| 11 | RS232 TXD | — | — | — | — | — | — | — | — |
| 12 | CAN H | — | — | — | — | — | — | — | — |
| 13 | Battery +12V | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| 14 | Ignition coil #4 | — | — | — | — | — | — | — | — |
| 15 | EGT in #2 | — | — | — | — | — | — | — | — |
| 16 | Knock Sensor in #2 | — | — | — | — | — | — | — | — |
| 17 | Analog In #3 | — | W39 | — | 0.5 | OEM-3-N | — | — | — |
| 18 | TPS In | — | W27 | — | 0.5 | OEM-3-F | — | — | — |
| 19 | WBO Ip | — | — | — | — | — | — | — | — |
| 2 | EGT in #1 | — | — | — | — | — | — | — | — |
| 20 | VSS In | — | W44 | — | 0.5 | OEM-1-M | — | — | — |
| 21 | Camsync In #1 | — | W18 | — | 0.5 | OEM-4-G | — | — | — |
| 22 | WBO Rcal | — | — | — | — | — | — | — | — |
| 23 | Switch #2 In | — | W46 | — | 0.5 | OEM-1-K | — | — | — |
| 24 | RS232 RXD | — | — | — | — | — | — | — | — |
| 25 | CAN L | — | — | — | — | — | — | — | — |
| 26 | +5V supply | — | W16 | — | 0.5 | OEM-3-I | — | — | — |
| 27 | Power Ground | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| 28 | Ecu Ground | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| 29 | Sensor Ground | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 3 | Knock Sensor in #1 | — | — | — | — | — | — | — | — |
| 30 | Analog In #4 | — | W40 | — | 0.5 | OEM-3-C | — | — | — |
| 31 | Analog In #1 | — | W26 | — | 0.5 | OEM-3-B | — | — | — |
| 32 | IAT In | — | W42 | — | 0.5 | OEM-3-K | — | — | — |
| 33 | WBO VGND | — | — | — | — | — | — | — | — |
| 34 | +5V supply | — | — | — | — | — | — | — | — |
| 35 | Analog In #5 | — | W41 | — | 0.5 | OEM-3-D | — | — | — |
| 36 | Switch #3 In | — | W47 | — | 0.5 | OEM-1-L | — | — | — |
| 37 | Analog In #6 | — | W43 | — | 0.5 | OEM-3-J | — | — | — |
| 38 | Sensor Ground | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| 39 | Sensor Ground | — | W15 | — | 0.5 | SP-0V-1 | — | — | — |
| 4 | Analog In #2 | — | W38 | — | 0.5 | OEM-3-H | — | — | — |
| 5 | CLT In | — | W28 | — | 0.5 | OEM-3-G | — | — | — |
| 6 | WBO Vs | — | — | — | — | — | — | — | — |
| 7 | Camsync In #2 | — | W19 | — | 0.5 | OEM-4-F | — | — | — |
| 8 | Primary trigger | — | W17 | — | 0.5 | OEM-4-E | — | — | — |
| 9 | Flex Fuel In | — | W48 | — | 0.5 | OEM-1-Q | — | — | — |
EMUBLACK-Grey
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Ignition coil #6 | — | — | — | — | — | — | — | — |
| 10 | H-Bridge #1 Winding B | — | — | — | — | — | — | — | — |
| 11 | H-Bridge #2 Winding B | — | — | — | — | — | — | — | — |
| 12 | AUX 5 | — | W34 | — | 0.5 | OEM-1-E | — | — | — |
| 13 | AUX 2 / Injector #8 | — | W30 | — | 0.5 | OEM-1-B | — | — | — |
| 14 | Injector #5 | — | W36 | — | 0.5 | OEM-4-O | — | — | — |
| 15 | Injector #2 | — | W23 | — | 0.5 | OEM-4-V | — | — | — |
| 16 | Ignition coil #2 | — | W21 | — | 0.5 | OEM-4-R | — | — | — |
| 17 | Power Ground | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
| 18 | Ignition +12V | — | — | — | — | — | — | — | — |
| 19 | WBO Heater | — | W33 | — | 0.5 | OEM-3-M | — | — | — |
| 2 | H-Bridge #1 Winding A | — | — | — | — | — | — | — | — |
| 20 | AUX 4 / Tacho | — | W32 | — | 0.5 | OEM-1-U | — | — | — |
| 21 | AUX 1 / Injector #7 | — | W29 | — | 0.5 | OEM-1-A | — | — | — |
| 22 | Injector #6 | — | W37 | — | 0.5 | OEM-4-P | — | — | — |
| 23 | Injector #3 | — | W24 | — | 0.5 | OEM-4-W | — | — | — |
| 24 | Power Ground | — | W10 | — | 0.85 | SP-GND-1 | — | — | — |
| 3 | H-Bridge #2 Winding A | — | — | — | — | — | — | — | — |
| 4 | AUX 6 | — | W35 | — | 0.5 | OEM-4-J | — | — | — |
| 5 | AUX 3 | — | W31 | — | 0.5 | OEM-1-G | — | — | — |
| 6 | Injector #4 | — | W25 | — | 0.5 | OEM-4-X | — | — | — |
| 7 | Injector #1 | — | W22 | — | 0.5 | OEM-4-U | — | — | — |
| 8 | Ignition coil #1 | — | W20 | — | 0.5 | OEM-4-N | — | — | — |
| 9 | Ignition coil #3 | — | — | — | — | — | — | — | — |
OEM-1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Cooling fan relay (low-side) | — | W29 | — | 0.5 | EMUBLACK-Grey-21 | — | — | — |
| B | A/C condenser fan relay | — | W30 | — | 0.5 | EMUBLACK-Grey-13 | — | — | — |
| C | Starter input (12V while cranking) | — | W45 | — | 0.5 | EMUBLACK-Black-10 | — | — | — |
| E | Check engine light (MIL) | — | W34 | — | 0.5 | EMUBLACK-Grey-12 | — | — | — |
| G | A/C clutch relay | — | W31 | — | 0.5 | EMUBLACK-Grey-5 | — | — | — |
| K | A/C pressure switch (A/C request) | — | W46 | — | 0.5 | EMUBLACK-Black-23 | — | — | — |
| L | Clutch switch | — | W47 | — | 0.5 | EMUBLACK-Black-36 | — | — | — |
| M | Vehicle speed sensor (VSS) | — | W44 | — | 0.5 | EMUBLACK-Black-20 | — | — | — |
| Q | Brake switch | — | W48 | — | 0.5 | EMUBLACK-Black-9 | — | — | — |
| U | Fuel pump relay (low-side) | — | W32 | — | 0.5 | EMUBLACK-Grey-20 | — | — | — |
OEM-3
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| B | MAF sensor input | — | W26 | — | 0.5 | EMUBLACK-Black-31 | — | — | — |
| C | Front O2 sensor input | — | W40 | — | 0.5 | EMUBLACK-Black-30 | — | — | — |
| D | Rear O2 sensor input | — | W41 | — | 0.5 | EMUBLACK-Black-35 | — | — | — |
| F | Throttle position (TPS) | — | W27 | — | 0.5 | EMUBLACK-Black-18 | — | — | — |
| G | Engine coolant temp (CLT) | — | W28 | — | 0.5 | EMUBLACK-Black-5 | — | — | — |
| H | EGR boost sensor | — | W38 | — | 0.5 | EMUBLACK-Black-4 | — | — | — |
| I | +5V sensor reference | — | W16 | — | 0.5 | EMUBLACK-Black-26 | — | — | — |
| J | EGR valve position sensor | — | W43 | — | 0.5 | EMUBLACK-Black-37 | — | — | — |
| K | Intake air temp (IAT) | — | W42 | — | 0.5 | EMUBLACK-Black-32 | — | — | — |
| L | Idle switch (closed throttle) | — | — | — | — | — | — | — | — |
| M | Front O2 heater control | — | W33 | — | 0.5 | EMUBLACK-Grey-19 | — | — | — |
| N | EGR boost sensor (2nd channel) | — | W39 | — | 0.5 | EMUBLACK-Black-17 | — | — | — |
| O | Sensor ground | — | W11 | — | 0.5 | SP-0V-1 | — | — | — |
| P | Power steering pressure switch | — | — | — | — | — | — | — | — |
OEM-4
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Chassis ground | — | W3 | — | 0.85 | SP-GND-1 | — | — | — |
| B | ECU power +12V (main relay) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| C | Chassis ground | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| D | Chassis ground | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| E | Crank position (CKP) sensor | — | W17 | — | 0.5 | EMUBLACK-Black-8 | — | — | — |
| F | CAS SGT (cam trigger) | — | W19 | — | 0.5 | EMUBLACK-Black-7 | — | — | — |
| G | CAS SGC (cam sync) | — | W18 | — | 0.5 | EMUBLACK-Black-21 | — | — | — |
| H | Crank pickup timing ground (CKP gnd) | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| I | Permanent +12V (battery) | — | — | — | — | — | — | — | — |
| J | PRC solenoid (FPR control) | — | W35 | — | 0.5 | EMUBLACK-Grey-4 | — | — | — |
| K | Chassis ground | — | W6 | — | 0.85 | SP-GND-1 | — | — | — |
| L | Tachometer output | — | — | — | — | — | — | — | — |
| N | Ignition coil trigger (cyl 1&4) | — | W20 | — | 0.5 | EMUBLACK-Grey-8 | — | — | — |
| O | EGR vent solenoid | — | W36 | — | 0.5 | EMUBLACK-Grey-14 | — | — | — |
| P | EGR vacuum solenoid | — | W37 | — | 0.5 | EMUBLACK-Grey-22 | — | — | — |
| Q | Idle air control (IAC) valve | — | — | — | — | — | — | — | — |
| R | Ignition coil trigger (cyl 2&3) | — | W21 | — | 0.5 | EMUBLACK-Grey-16 | — | — | — |
| T | EVAP purge solenoid | — | — | — | — | — | — | — | — |
| U | Injector 1 (cyl 1) | — | W22 | — | 0.5 | EMUBLACK-Grey-7 | — | — | — |
| V | Injector 2 (cyl 2) | — | W23 | — | 0.5 | EMUBLACK-Grey-15 | — | — | — |
| W | Injector 3 (cyl 3) | — | W24 | — | 0.5 | EMUBLACK-Grey-23 | — | — | — |
| X | Injector 4 (cyl 4) | — | W25 | — | 0.5 | EMUBLACK-Grey-6 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W11 | — | 0.5 | OEM-3-O | — | — | — |
| 1 | — | — | W12 | — | 0.5 | OEM-4-H | — | — | — |
| 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-4-B | — | — | — |
| 1 | — | — | W2 | — | 0.85 | EMUBLACK-Black-13 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W3 | — | 0.85 | OEM-4-A | — | — | — |
| 1 | — | — | W4 | — | 0.85 | OEM-4-C | — | — | — |
| 1 | — | — | W5 | — | 0.85 | OEM-4-D | — | — | — |
| 1 | — | — | W6 | — | 0.85 | OEM-4-K | — | — | — |
| 1 | — | — | W7 | — | 0.85 | EMUBLACK-Black-27 | — | — | — |
| 1 | — | — | W8 | — | 0.85 | EMUBLACK-Black-28 | — | — | — |
| 1 | — | — | W9 | — | 0.85 | EMUBLACK-Grey-17 | — | — | — |
| 1 | — | — | W10 | — | 0.85 | EMUBLACK-Grey-24 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-1-A | Cooling fan relay (low-side) | low_side_out | EMUBLACK-Grey-21 | AUX 1 / Injector #7 | low_side_out | corroborated | |
| OEM-1-B | A/C condenser fan relay | low_side_out | EMUBLACK-Grey-13 | AUX 2 / Injector #8 | low_side_out | corroborated | |
| OEM-1-C | Starter input (12V while cranking) | digital_in | EMUBLACK-Black-10 | Switch #1 In | digital_in | corroborated | |
| OEM-1-E | Check engine light (MIL) | low_side_out | EMUBLACK-Grey-12 | AUX 5 | low_side_out | corroborated | |
| OEM-1-G | A/C clutch relay | low_side_out | EMUBLACK-Grey-5 | AUX 3 | low_side_out | corroborated | |
| OEM-1-K | A/C pressure switch (A/C request) | digital_in | EMUBLACK-Black-23 | Switch #2 In | digital_in | corroborated | |
| OEM-1-L | Clutch switch | digital_in | EMUBLACK-Black-36 | Switch #3 In | digital_in | corroborated | |
| OEM-1-M | Vehicle speed sensor (VSS) | digital_in | EMUBLACK-Black-20 | VSS In | digital_in | corroborated | |
| OEM-1-Q | Brake switch | digital_in | EMUBLACK-Black-9 | Flex Fuel In | analog_in | corroborated | |
| OEM-1-U | Fuel pump relay (low-side) | low_side_out | EMUBLACK-Grey-20 | AUX 4 / Tacho | low_side_out | corroborated | |
| OEM-3-B | MAF sensor input | analog_in | EMUBLACK-Black-31 | Analog In #1 | analog_in | corroborated | |
| OEM-3-C | Front O2 sensor input | lambda_nb_in | EMUBLACK-Black-30 | Analog In #4 | analog_in | corroborated | |
| OEM-3-D | Rear O2 sensor input | lambda_nb_in | EMUBLACK-Black-35 | Analog In #5 | analog_in | corroborated | |
| OEM-3-F | Throttle position (TPS) | analog_in | EMUBLACK-Black-18 | TPS In | analog_in | corroborated | |
| OEM-3-G | Engine coolant temp (CLT) | temp_in | EMUBLACK-Black-5 | CLT In | temp_in | corroborated | |
| OEM-3-H | EGR boost sensor | analog_in | EMUBLACK-Black-4 | Analog In #2 | analog_in | corroborated | |
| OEM-3-I | +5V sensor reference | vref | EMUBLACK-Black-26 | +5V supply | vref | corroborated | |
| OEM-3-J | EGR valve position sensor | analog_in | EMUBLACK-Black-37 | Analog In #6 | analog_in | corroborated | |
| OEM-3-K | Intake air temp (IAT) | temp_in | EMUBLACK-Black-32 | IAT In | temp_in | corroborated | |
| OEM-3-L | Idle switch (closed throttle) | digital_in | — | — | — | corroborated | |
| OEM-3-M | Front O2 heater control | low_side_out | EMUBLACK-Grey-19 | WBO Heater | low_side_out | corroborated | |
| OEM-3-N | EGR boost sensor (2nd channel) | analog_in | EMUBLACK-Black-17 | Analog In #3 | analog_in | corroborated | |
| OEM-3-O | Sensor ground | sensor_ground | EMUBLACK-Black-29 + EMUBLACK-Black-38 + EMUBLACK-Black-39 | Sensor Ground + Sensor Ground + Sensor Ground | sensor_ground | corroborated | |
| OEM-3-P | Power steering pressure switch | digital_in | — | — | — | corroborated | |
| OEM-4-A | Chassis ground | ground | EMUBLACK-Black-27 + EMUBLACK-Black-28 + EMUBLACK-Grey-17 + EMUBLACK-Grey-24 | Power Ground + Ecu Ground + Power Ground + Power Ground | ground | corroborated | |
| OEM-4-B | ECU power +12V (main relay) | power_in | EMUBLACK-Black-13 | Battery +12V | power_in | corroborated | |
| OEM-4-C | Chassis ground | ground | EMUBLACK-Black-27 + EMUBLACK-Black-28 + EMUBLACK-Grey-17 + EMUBLACK-Grey-24 | Power Ground + Ecu Ground + Power Ground + Power Ground | ground | corroborated | |
| OEM-4-D | Chassis ground | ground | EMUBLACK-Black-27 + EMUBLACK-Black-28 + EMUBLACK-Grey-17 + EMUBLACK-Grey-24 | Power Ground + Ecu Ground + Power Ground + Power Ground | ground | corroborated | |
| OEM-4-E | Crank position (CKP) sensor | trigger_in | EMUBLACK-Black-8 | Primary trigger | trigger_in | corroborated | |
| OEM-4-F | CAS SGT (cam trigger) | trigger_in | EMUBLACK-Black-7 | Camsync In #2 | trigger_in | corroborated | |
| OEM-4-G | CAS SGC (cam sync) | trigger_in | EMUBLACK-Black-21 | Camsync In #1 | trigger_in | corroborated | |
| OEM-4-H | Crank pickup timing ground (CKP gnd) | sensor_ground | EMUBLACK-Black-29 + EMUBLACK-Black-38 + EMUBLACK-Black-39 | Sensor Ground + Sensor Ground + Sensor Ground | sensor_ground | corroborated | |
| OEM-4-I | Permanent +12V (battery) | power_in | — | — | — | corroborated | |
| OEM-4-J | PRC solenoid (FPR control) | low_side_out | EMUBLACK-Grey-4 | AUX 6 | low_side_out | corroborated | |
| OEM-4-K | Chassis ground | ground | EMUBLACK-Black-27 + EMUBLACK-Black-28 + EMUBLACK-Grey-17 + EMUBLACK-Grey-24 | Power Ground + Ecu Ground + Power Ground + Power Ground | ground | corroborated | |
| OEM-4-L | Tachometer output | tacho_out | — | — | — | corroborated | |
| OEM-4-N | Ignition coil trigger (cyl 1&4) | ignition_out | EMUBLACK-Grey-8 | Ignition coil #1 | ignition_out | corroborated | |
| OEM-4-O | EGR vent solenoid | low_side_out | EMUBLACK-Grey-14 | Injector #5 | injector_out | corroborated | |
| OEM-4-P | EGR vacuum solenoid | low_side_out | EMUBLACK-Grey-22 | Injector #6 | injector_out | corroborated | |
| OEM-4-Q | Idle air control (IAC) valve | low_side_out | — | — | — | corroborated | |
| OEM-4-R | Ignition coil trigger (cyl 2&3) | ignition_out | EMUBLACK-Grey-16 | Ignition coil #2 | ignition_out | corroborated | |
| OEM-4-T | EVAP purge solenoid | low_side_out | — | — | — | corroborated | |
| OEM-4-U | Injector 1 (cyl 1) | injector_out | EMUBLACK-Grey-7 | Injector #1 | injector_out | corroborated | |
| OEM-4-V | Injector 2 (cyl 2) | injector_out | EMUBLACK-Grey-15 | Injector #2 | injector_out | corroborated | |
| OEM-4-W | Injector 3 (cyl 3) | injector_out | EMUBLACK-Grey-23 | Injector #3 | injector_out | corroborated | |
| OEM-4-X | Injector 4 (cyl 4) | injector_out | EMUBLACK-Grey-6 | Injector #4 | injector_out | corroborated |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-4-B | SP-14V-1 | 0.85 | no route | ECU power +12V (main relay) | — | |
| W2 | SP-14V-1 | EMUBLACK-Black-13 | 0.85 | no route | Battery +12V | — | |
| W3 | OEM-4-A | SP-GND-1 | 0.85 | no route | Chassis ground | — | |
| W4 | OEM-4-C | SP-GND-1 | 0.85 | no route | Chassis ground | — | |
| W5 | OEM-4-D | SP-GND-1 | 0.85 | no route | Chassis ground | — | |
| W6 | OEM-4-K | SP-GND-1 | 0.85 | no route | Chassis ground | — | |
| W7 | SP-GND-1 | EMUBLACK-Black-27 | 0.85 | no route | Power Ground | — | |
| W8 | SP-GND-1 | EMUBLACK-Black-28 | 0.85 | no route | Ecu Ground | — | |
| W9 | SP-GND-1 | EMUBLACK-Grey-17 | 0.85 | no route | Power Ground | — | |
| W10 | SP-GND-1 | EMUBLACK-Grey-24 | 0.85 | no route | Power Ground | — | |
| W11 | OEM-3-O | SP-0V-1 | 0.5 | no route | Sensor ground | — | |
| W12 | OEM-4-H | SP-0V-1 | 0.5 | no route | Crank pickup timing ground (CKP gnd) | — | |
| 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-3-I | EMUBLACK-Black-26 | 0.5 | no route | +5V sensor reference | — | |
| W17 | OEM-4-E | EMUBLACK-Black-8 | 0.5 | no route | Crank position (CKP) sensor | — | |
| W18 | OEM-4-G | EMUBLACK-Black-21 | 0.5 | no route | CAS SGC (cam sync) | — | |
| W19 | OEM-4-F | EMUBLACK-Black-7 | 0.5 | no route | CAS SGT (cam trigger) | — | |
| W20 | OEM-4-N | EMUBLACK-Grey-8 | 0.5 | no route | Ignition coil trigger (cyl 1&4) | — | |
| W21 | OEM-4-R | EMUBLACK-Grey-16 | 0.5 | no route | Ignition coil trigger (cyl 2&3) | — | |
| W22 | OEM-4-U | EMUBLACK-Grey-7 | 0.5 | no route | Injector 1 (cyl 1) | — | |
| W23 | OEM-4-V | EMUBLACK-Grey-15 | 0.5 | no route | Injector 2 (cyl 2) | — | |
| W24 | OEM-4-W | EMUBLACK-Grey-23 | 0.5 | no route | Injector 3 (cyl 3) | — | |
| W25 | OEM-4-X | EMUBLACK-Grey-6 | 0.5 | no route | Injector 4 (cyl 4) | — | |
| W26 | OEM-3-B | EMUBLACK-Black-31 | 0.5 | no route | MAF sensor input | — | |
| W27 | OEM-3-F | EMUBLACK-Black-18 | 0.5 | no route | Throttle position (TPS) | — | |
| W28 | OEM-3-G | EMUBLACK-Black-5 | 0.5 | no route | Engine coolant temp (CLT) | — | |
| W29 | OEM-1-A | EMUBLACK-Grey-21 | 0.5 | no route | Cooling fan relay (low-side) | — | |
| W30 | OEM-1-B | EMUBLACK-Grey-13 | 0.5 | no route | A/C condenser fan relay | — | |
| W31 | OEM-1-G | EMUBLACK-Grey-5 | 0.5 | no route | A/C clutch relay | — | |
| W32 | OEM-1-U | EMUBLACK-Grey-20 | 0.5 | no route | Fuel pump relay (low-side) | — | |
| W33 | OEM-3-M | EMUBLACK-Grey-19 | 0.5 | no route | Front O2 heater control | — | |
| W34 | OEM-1-E | EMUBLACK-Grey-12 | 0.5 | no route | Check engine light (MIL) | — | |
| W35 | OEM-4-J | EMUBLACK-Grey-4 | 0.5 | no route | PRC solenoid (FPR control) | — | |
| W36 | OEM-4-O | EMUBLACK-Grey-14 | 0.5 | no route | EGR vent solenoid | — | |
| W37 | OEM-4-P | EMUBLACK-Grey-22 | 0.5 | no route | EGR vacuum solenoid | — | |
| W38 | OEM-3-H | EMUBLACK-Black-4 | 0.5 | no route | EGR boost sensor | — | |
| W39 | OEM-3-N | EMUBLACK-Black-17 | 0.5 | no route | EGR boost sensor (2nd channel) | — | |
| W40 | OEM-3-C | EMUBLACK-Black-30 | 0.5 | no route | Front O2 sensor input | — | |
| W41 | OEM-3-D | EMUBLACK-Black-35 | 0.5 | no route | Rear O2 sensor input | — | |
| W42 | OEM-3-K | EMUBLACK-Black-32 | 0.5 | no route | Intake air temp (IAT) | — | |
| W43 | OEM-3-J | EMUBLACK-Black-37 | 0.5 | no route | EGR valve position sensor | — | |
| W44 | OEM-1-M | EMUBLACK-Black-20 | 0.5 | no route | Vehicle speed sensor (VSS) | — | |
| W45 | OEM-1-C | EMUBLACK-Black-10 | 0.5 | no route | Starter input (12V while cranking) | — | |
| W46 | OEM-1-K | EMUBLACK-Black-23 | 0.5 | no route | A/C pressure switch (A/C request) | — | |
| W47 | OEM-1-L | EMUBLACK-Black-36 | 0.5 | no route | Clutch switch | — | |
| W48 | OEM-1-Q | EMUBLACK-Black-9 | 0.5 | no route | Brake 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 (4)
| Severity | Code | Subject | Message |
|---|---|---|---|
| warn | NET_FAMILY | OEM-1-Q ↔ EMUBLACK-Black-9 | OEM-1-Q "Brake switch" [digital_in] is wired to EMUBLACK-Black-9 "Flex Fuel In" [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-4-O ↔ EMUBLACK-Grey-14 | OEM-4-O "EGR vent solenoid" [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 | NET_FAMILY | OEM-4-P ↔ EMUBLACK-Grey-22 | OEM-4-P "EGR vacuum solenoid" [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 | UNMAPPED | OEM | 5 optional OEM pins are not mapped: OEM-3-L Idle switch (closed throttle); OEM-3-P Power steering pressure switch; OEM-4-L Tachometer output; OEM-4-Q Idle air control (IAC) valve; OEM-4-T EVAP purge solenoid |
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-4-I | 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-4 I: Permanent +12V (battery): ECUMASTER EMU Black has no battery-constant input; not needed - OEM-4 Q: Idle air control (IAC) valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on ECUMASTER EMU Black - OEM-4 T: EVAP purge solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on ECUMASTER EMU Black - OEM-4 L: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on ECUMASTER EMU Black - OEM-3 L: Idle switch (closed throttle): no free switch_in/frequency_in/analog_0_5 on ECUMASTER EMU Black - OEM-3 P: Power steering pressure switch: no free switch_in/frequency_in/analog_0_5 on ECUMASTER EMU Black - 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 | AEM EMS 30-1720 Plug-and-Play adapter manual (1996-97 Miata) | https://static.summitracing.com/global/images/instructions/avm-30-1720.pdf | — | — | — |
| 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 |
| 3 | community_copy | Mellens.net: 1996 Mazda Miata wiring diagrams (FSM-derived) | http://www.mellens.net/mazda/mazda_miata_extra_manual/1996_wiring.pdf | — | — | — |