Mazda RX-7 FD 1992-2002 (13B-REW twin-turbo) → Speeduino Speeduino v0.4 (auto)
Mazda RX-7 FD 1992-2002 (13B-REW twin-turbo) — Speeduino — Speeduino
⚠ NOT CHECKED. Don't build from this.
Drawn by Michael Gnankou · Rev 0 · draft · 2026-10-20
Before you start
Not confident with automotive wiring? Have a professional harness builder or tuner do it, or check your work before first power-up. A wiring mistake can damage the ECU, the engine or the car, or start a fire.
| Status | draft · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | none |
| Size of the job | 41 wires · 11 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-D-4A | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | OEM-D-4E | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | NEW-KEYON-1 | MAIN-R-COIL+ | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | NEW-BATT-1 | MAIN-R-IN | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | MAIN-R-COIL- | SP-GND-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | MAIN-R-OUT | SPEEDUINO-PWR-12V | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-A-1AF | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | OEM-A-1AJ | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | OEM-A-1L | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-GND-1 | SPEEDUINO-A-10 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | SP-GND-1 | SPEEDUINO-A-9 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-A-1AB | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | OEM-A-1X | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-C-3AB | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-C-3S | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | SP-0V-1 | SPEEDUINO-A-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | SP-0V-1 | SPEEDUINO-A-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-C-3A | SPEEDUINO-A-13 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-C-3R | SPEEDUINO-A-25 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-C-3U | SPEEDUINO-A-24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-D-4AF | SPEEDUINO-A-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-D-4AJ | SPEEDUINO-A-34 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-D-4AN | SPEEDUINO-A-33 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-A-1Q | SPEEDUINO-A-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-A-1U | SPEEDUINO-A-2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-A-1Y | SPEEDUINO-A-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-A-1AC | SPEEDUINO-A-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-D-4AH | SPEEDUINO-A-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-C-3I | SPEEDUINO-A-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-C-3W | SPEEDUINO-A-19 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-A-1H | SPEEDUINO-A-16 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-D-4D | SPEEDUINO-A-15 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-D-4F | SPEEDUINO-A-36 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-D-4G | SPEEDUINO-A-35 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-D-4I | SPEEDUINO-A-37 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-D-4K | SPEEDUINO-A-38 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-D-4M | SPEEDUINO-A-17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-C-3D | SPEEDUINO-A-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-C-3T | SPEEDUINO-A-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-D-4Q | SPEEDUINO-A-14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-D-4AA | SPEEDUINO-A-18 | 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 | MAIN-R-COIL- | MAIN-R-OUT | open (OL) | power ground must not touch +12 V supply | |
| 2 | MAIN-R-COIL- | NEW-BATT-1 | open (OL) | power ground must not touch +12 V supply | |
| 3 | MAIN-R-COIL- | NEW-KEYON-1 | open (OL) | power ground must not touch +12 V supply | |
| 4 | MAIN-R-COIL- | OEM-D-4A | open (OL) | power ground must not touch +12 V supply | |
| 5 | MAIN-R-COIL- | SPEEDUINO-A-13 | open (OL) | power ground must not touch 5 V sensor reference | |
| 6 | SPEEDUINO-A-12 | MAIN-R-OUT | open (OL) | sensor ground must not touch +12 V supply | |
| 7 | SPEEDUINO-A-12 | NEW-BATT-1 | open (OL) | sensor ground must not touch +12 V supply | |
| 8 | SPEEDUINO-A-12 | NEW-KEYON-1 | open (OL) | sensor ground must not touch +12 V supply | |
| 9 | SPEEDUINO-A-12 | OEM-D-4A | open (OL) | sensor ground must not touch +12 V supply | |
| 10 | SPEEDUINO-A-12 | SPEEDUINO-A-13 | open (OL) | sensor ground must not touch 5 V sensor reference | |
| 11 | SPEEDUINO-A-13 | MAIN-R-OUT | open (OL) | 5 V sensor reference must not touch +12 V supply | |
| 12 | SPEEDUINO-A-13 | NEW-BATT-1 | open (OL) | 5 V sensor reference must not touch +12 V supply | |
| 13 | SPEEDUINO-A-13 | NEW-KEYON-1 | open (OL) | 5 V sensor reference must not touch +12 V supply | |
| 14 | SPEEDUINO-A-13 | OEM-D-4A | open (OL) | 5 V sensor reference 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
MAIN-R
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| COIL+ | Relay coil positive (ignition-switched +12V) | — | W3 | — | 0.5 | NEW-KEYON-1 | — | — | — |
| COIL- | Relay coil negative (ECU low-side driver) | — | W5 | — | 0.5 | SP-GND-1 | — | — | — |
| IN | Relay contact input (battery + via main fuse) | — | W4 | — | 0.85 | NEW-BATT-1 | — | — | — |
| OUT | Relay contact output (switched +12V bus) | — | W6 | — | 0.85 | SPEEDUINO-PWR-12V | — | — | — |
NEW-BATT
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W4 | — | 0.85 | MAIN-R-IN | — | — | — |
NEW-KEYON
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W3 | — | 0.5 | MAIN-R-COIL+ | — | — | — |
OEM-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1AA | OMP stepper phase B1 | — | — | — | — | — | — | — | — |
| 1AB | Sensor ground | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| 1AC | Injector 4 (rear secondary) | — | W27 | — | 0.5 | SPEEDUINO-A-5 | — | — | — |
| 1AE | OMP stepper phase A1 | — | — | — | — | — | — | — | — |
| 1AF | Power ground | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| 1AJ | Power ground | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| 1C | Idle speed control (ISC) solenoid | — | — | — | — | — | — | — | — |
| 1E | Turbo charge control solenoid | — | — | — | — | — | — | — | — |
| 1G | Purge solenoid | — | — | — | — | — | — | — | — |
| 1H | Cooling fan relay (low speed) | — | W31 | — | 0.5 | SPEEDUINO-A-16 | — | — | — |
| 1I | Turbo charge relief solenoid | — | — | — | — | — | — | — | — |
| 1K | Turbo pre-control solenoid | — | — | — | — | — | — | — | — |
| 1L | Power ground | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
| 1M | Turbo control solenoid | — | — | — | — | — | — | — | — |
| 1O | Boost control solenoid | — | — | — | — | — | — | — | — |
| 1Q | Injector 1 (front primary) | — | W24 | — | 0.5 | SPEEDUINO-A-1 | — | — | — |
| 1S | OMP stepper phase B2 | — | — | — | — | — | — | — | — |
| 1U | Injector 2 (rear primary) | — | W25 | — | 0.5 | SPEEDUINO-A-2 | — | — | — |
| 1W | OMP stepper phase A2 | — | — | — | — | — | — | — | — |
| 1X | Sensor ground | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 1Y | Injector 3 (front secondary) | — | W26 | — | 0.5 | SPEEDUINO-A-3 | — | — | — |
OEM-C
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 3A | +5V sensor supply | — | W18 | — | 0.5 | SPEEDUINO-A-13 | — | — | — |
| 3AB | Sensor ground | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| 3D | O2 sensor (narrowband) | — | W38 | — | 0.5 | SPEEDUINO-A-21 | — | — | — |
| 3G | Fuel pressure regulator control (PRC) solenoid | — | — | — | — | — | — | — | — |
| 3H | OMP position sensor | — | — | — | — | — | — | — | — |
| 3I | Throttle position (TPS, full range) | — | W29 | — | 0.5 | SPEEDUINO-A-22 | — | — | — |
| 3O | Knock sensor | — | — | — | — | — | — | — | — |
| 3R | Crank position (CAS NE) | — | W19 | — | 0.5 | SPEEDUINO-A-25 | — | — | — |
| 3S | Sensor ground (CAS) | — | W15 | — | 0.5 | SP-0V-1 | — | — | — |
| 3T | Intake air temperature (IAT) | — | W39 | — | 0.5 | SPEEDUINO-A-20 | — | — | — |
| 3U | Home position (CAS G) | — | W20 | — | 0.5 | SPEEDUINO-A-24 | — | — | — |
| 3V | Fuel temperature | — | — | — | — | — | — | — | — |
| 3W | Coolant temperature (ECT) | — | W30 | — | 0.5 | SPEEDUINO-A-19 | — | — | — |
OEM-D
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 4A | ECU main power (+12V via main relay/ECR) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| 4AA | Brake pedal switch | — | W41 | — | 0.5 | SPEEDUINO-A-18 | — | — | — |
| 4AF | Ignition front trailing | — | W21 | — | 0.5 | SPEEDUINO-A-7 | — | — | — |
| 4AH | MAP sensor (PIM) | — | W28 | — | 0.5 | SPEEDUINO-A-11 | — | — | — |
| 4AJ | Ignition rear trailing | — | W22 | — | 0.5 | SPEEDUINO-A-34 | — | — | — |
| 4AN | Ignition leading (wasted spark) | — | W23 | — | 0.5 | SPEEDUINO-A-33 | — | — | — |
| 4B | Battery constant (+12V) | — | — | — | — | — | — | — | — |
| 4C | Start signal (STA) | — | — | — | — | — | — | — | — |
| 4D | Air pump clutch relay | — | W32 | — | 0.5 | SPEEDUINO-A-15 | — | — | — |
| 4E | ECU main power (+12V via main relay/ECR) | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| 4F | Fuel pump speed relay | — | W33 | — | 0.5 | SPEEDUINO-A-36 | — | — | — |
| 4G | Fuel pump relay | — | W34 | — | 0.5 | SPEEDUINO-A-35 | — | — | — |
| 4I | A/C relay | — | W35 | — | 0.5 | SPEEDUINO-A-37 | — | — | — |
| 4K | Cooling fan relay (low speed) | — | W36 | — | 0.5 | SPEEDUINO-A-38 | — | — | — |
| 4L | Cooling fan relay (high speed) | — | — | — | — | — | — | — | — |
| 4M | Tachometer output | — | W37 | — | 0.5 | SPEEDUINO-A-17 | — | — | — |
| 4Q | Vehicle speed sensor | — | W40 | — | 0.5 | SPEEDUINO-A-14 | — | — | — |
| 4S | Clutch switch | — | — | — | — | — | — | — | — |
| 4V | A/C request | — | — | — | — | — | — | — | — |
| 4W | Power steering pressure switch | — | — | — | — | — | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W12 | — | 0.5 | OEM-A-1AB | — | — | — |
| 1 | — | — | W13 | — | 0.5 | OEM-A-1X | — | — | — |
| 1 | — | — | W14 | — | 0.5 | OEM-C-3AB | — | — | — |
| 1 | — | — | W15 | — | 0.5 | OEM-C-3S | — | — | — |
| 1 | — | — | W16 | — | 0.5 | SPEEDUINO-A-12 | — | — | — |
| 1 | — | — | W17 | — | 0.5 | SPEEDUINO-A-23 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-D-4A | — | — | — |
| 1 | — | — | W2 | — | 0.85 | OEM-D-4E | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W5 | — | 0.5 | MAIN-R-COIL- | — | — | — |
| 1 | — | — | W7 | — | 0.85 | OEM-A-1AF | — | — | — |
| 1 | — | — | W8 | — | 0.85 | OEM-A-1AJ | — | — | — |
| 1 | — | — | W9 | — | 0.85 | OEM-A-1L | — | — | — |
| 1 | — | — | W10 | — | 0.85 | SPEEDUINO-A-10 | — | — | — |
| 1 | — | — | W11 | — | 0.85 | SPEEDUINO-A-9 | — | — | — |
SPEEDUINO-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Injector 1 | — | W24 | — | 0.5 | OEM-A-1Q | — | — | — |
| 10 | Ground | — | W10 | — | 0.85 | SP-GND-1 | — | — | — |
| 11 | MAP sensor (0-5V) | — | W28 | — | 0.5 | OEM-D-4AH | — | — | — |
| 12 | Ground | — | W16 | — | 0.5 | SP-0V-1 | — | — | — |
| 13 | 5V | — | W18 | — | 0.5 | OEM-C-3A | — | — | — |
| 14 | Proto area 1 (flex fuel) | — | W40 | — | 0.5 | OEM-D-4Q | — | — | — |
| 15 | Proto area 2 (fan) | — | W32 | — | 0.5 | OEM-D-4D | — | — | — |
| 16 | Proto area 3 (fuel pump) | — | W31 | — | 0.5 | OEM-A-1H | — | — | — |
| 17 | Proto area 4 (tachometer) | — | W37 | — | 0.5 | OEM-D-4M | — | — | — |
| 18 | Proto area 5 (clutch) | — | W41 | — | 0.5 | OEM-D-4AA | — | — | — |
| 19 | Coolant temp (CLT) | — | W30 | — | 0.5 | OEM-C-3W | — | — | — |
| 2 | Injector 2 | — | W25 | — | 0.5 | OEM-A-1U | — | — | — |
| 20 | Inlet air temp (IAT) | — | W39 | — | 0.5 | OEM-C-3T | — | — | — |
| 21 | O2 sensor | — | W38 | — | 0.5 | OEM-C-3D | — | — | — |
| 22 | TPS input | — | W29 | — | 0.5 | OEM-C-3I | — | — | — |
| 23 | Ground | — | W17 | — | 0.5 | SP-0V-1 | — | — | — |
| 24 | Cam input / VR2+ | — | W20 | — | 0.5 | OEM-C-3U | — | — | — |
| 25 | Crank input / VR1+ | — | W19 | — | 0.5 | OEM-C-3R | — | — | — |
| 26 | VR2- | — | — | — | — | — | — | — | — |
| 27 | VR1- | — | — | — | — | — | — | — | — |
| 28 | 5V | — | — | — | — | — | — | — | — |
| 29 | Idle stepper 2B | — | — | — | — | — | — | — | — |
| 3 | Injector 3 | — | W26 | — | 0.5 | OEM-A-1Y | — | — | — |
| 30 | Idle stepper 2A | — | — | — | — | — | — | — | — |
| 31 | Idle stepper 1A | — | — | — | — | — | — | — | — |
| 32 | Idle stepper 1B | — | — | — | — | — | — | — | — |
| 33 | Ignition 3 | — | W23 | — | 0.5 | OEM-D-4AN | — | — | — |
| 34 | Ignition 2 | — | W22 | — | 0.5 | OEM-D-4AJ | — | — | — |
| 35 | Boost | — | W34 | — | 0.5 | OEM-D-4G | — | — | — |
| 36 | Idle 2 (3-wire idle) | — | W33 | — | 0.5 | OEM-D-4F | — | — | — |
| 37 | PWM idle | — | W35 | — | 0.5 | OEM-D-4I | — | — | — |
| 38 | VVT | — | W36 | — | 0.5 | OEM-D-4K | — | — | — |
| 5 | Injector 4 | — | W27 | — | 0.5 | OEM-A-1AC | — | — | — |
| 7 | Ignition 1 | — | W21 | — | 0.5 | OEM-D-4AF | — | — | — |
| 8 | Ignition 4 | — | — | — | — | — | — | — | — |
| 9 | Ground | — | W11 | — | 0.85 | SP-GND-1 | — | — | — |
SPEEDUINO-PWR
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 12V | Main power (+12 V switched) | — | W6 | — | 0.85 | MAIN-R-OUT | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-A-1AA | OMP stepper phase B1 | hbridge_out | — | — | — | single_source | |
| OEM-A-1AB | Sensor ground | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-A-1AC | Injector 4 (rear secondary) | injector_out | SPEEDUINO-A-5 | Injector 4 | injector_out | single_source | |
| OEM-A-1AE | OMP stepper phase A1 | hbridge_out | — | — | — | single_source | |
| OEM-A-1AF | Power ground | ground | MAIN-R-COIL- + SPEEDUINO-A-10 + SPEEDUINO-A-9 | Relay coil negative (ECU low-side driver) + Ground + Ground | ground + load | single_source | |
| OEM-A-1AJ | Power ground | ground | MAIN-R-COIL- + SPEEDUINO-A-10 + SPEEDUINO-A-9 | Relay coil negative (ECU low-side driver) + Ground + Ground | ground + load | single_source | |
| OEM-A-1C | Idle speed control (ISC) solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-1E | Turbo charge control solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-1G | Purge solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-1H | Cooling fan relay (low speed) | low_side_out | SPEEDUINO-A-16 | Proto area 3 (fuel pump) | low_side_out | single_source | |
| OEM-A-1I | Turbo charge relief solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-1K | Turbo pre-control solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-1L | Power ground | ground | MAIN-R-COIL- + SPEEDUINO-A-10 + SPEEDUINO-A-9 | Relay coil negative (ECU low-side driver) + Ground + Ground | ground + load | single_source | |
| OEM-A-1M | Turbo control solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-1O | Boost control solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-1Q | Injector 1 (front primary) | injector_out | SPEEDUINO-A-1 | Injector 1 | injector_out | single_source | |
| OEM-A-1S | OMP stepper phase B2 | hbridge_out | — | — | — | single_source | |
| OEM-A-1U | Injector 2 (rear primary) | injector_out | SPEEDUINO-A-2 | Injector 2 | injector_out | single_source | |
| OEM-A-1W | OMP stepper phase A2 | hbridge_out | — | — | — | single_source | |
| OEM-A-1X | Sensor ground | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-A-1Y | Injector 3 (front secondary) | injector_out | SPEEDUINO-A-3 | Injector 3 | injector_out | single_source | |
| OEM-C-3A | +5V sensor supply | vref | SPEEDUINO-A-13 | 5V | vref | single_source | |
| OEM-C-3AB | Sensor ground | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-C-3D | O2 sensor (narrowband) | lambda_nb_in | SPEEDUINO-A-21 | O2 sensor | lambda_nb_in | single_source | |
| OEM-C-3G | Fuel pressure regulator control (PRC) solenoid | low_side_out | — | — | — | single_source | |
| OEM-C-3H | OMP position sensor | analog_in | — | — | — | single_source | |
| OEM-C-3I | Throttle position (TPS, full range) | analog_in | SPEEDUINO-A-22 | TPS input | analog_in | single_source | |
| OEM-C-3O | Knock sensor | knock_in | — | — | — | single_source | |
| OEM-C-3R | Crank position (CAS NE) | trigger_in | SPEEDUINO-A-25 | Crank input / VR1+ | trigger_in | single_source | |
| OEM-C-3S | Sensor ground (CAS) | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-C-3T | Intake air temperature (IAT) | temp_in | SPEEDUINO-A-20 | Inlet air temp (IAT) | temp_in | single_source | |
| OEM-C-3U | Home position (CAS G) | trigger_in | SPEEDUINO-A-24 | Cam input / VR2+ | trigger_in | single_source | |
| OEM-C-3V | Fuel temperature | temp_in | — | — | — | single_source | |
| OEM-C-3W | Coolant temperature (ECT) | temp_in | SPEEDUINO-A-19 | Coolant temp (CLT) | temp_in | single_source | |
| OEM-D-4A | ECU main power (+12V via main relay/ECR) | power_in | — | — | — | single_source | |
| OEM-D-4AA | Brake pedal switch | digital_in | SPEEDUINO-A-18 | Proto area 5 (clutch) | digital_in | single_source | |
| OEM-D-4AF | Ignition front trailing | ignition_out | SPEEDUINO-A-7 | Ignition 1 | ignition_out | single_source | |
| OEM-D-4AH | MAP sensor (PIM) | analog_in | SPEEDUINO-A-11 | MAP sensor (0-5V) | analog_in | single_source | |
| OEM-D-4AJ | Ignition rear trailing | ignition_out | SPEEDUINO-A-34 | Ignition 2 | ignition_out | single_source | |
| OEM-D-4AN | Ignition leading (wasted spark) | ignition_out | SPEEDUINO-A-33 | Ignition 3 | ignition_out | single_source | |
| OEM-D-4B | Battery constant (+12V) | power_in | — | — | — | single_source | |
| OEM-D-4C | Start signal (STA) | digital_in | — | — | — | single_source | |
| OEM-D-4D | Air pump clutch relay | low_side_out | SPEEDUINO-A-15 | Proto area 2 (fan) | low_side_out | single_source | |
| OEM-D-4E | ECU main power (+12V via main relay/ECR) | power_in | — | — | — | single_source | |
| OEM-D-4F | Fuel pump speed relay | low_side_out | SPEEDUINO-A-36 | Idle 2 (3-wire idle) | low_side_out | single_source | |
| OEM-D-4G | Fuel pump relay | low_side_out | SPEEDUINO-A-35 | Boost | low_side_out | single_source | |
| OEM-D-4I | A/C relay | low_side_out | SPEEDUINO-A-37 | PWM idle | low_side_out | single_source | |
| OEM-D-4K | Cooling fan relay (low speed) | low_side_out | SPEEDUINO-A-38 | VVT | low_side_out | single_source | |
| OEM-D-4L | Cooling fan relay (high speed) | low_side_out | — | — | — | single_source | |
| OEM-D-4M | Tachometer output | tacho_out | SPEEDUINO-A-17 | Proto area 4 (tachometer) | tacho_out | single_source | |
| OEM-D-4Q | Vehicle speed sensor | digital_in | SPEEDUINO-A-14 | Proto area 1 (flex fuel) | digital_in | single_source | |
| OEM-D-4S | Clutch switch | digital_in | — | — | — | single_source | |
| OEM-D-4V | A/C request | digital_in | — | — | — | single_source | |
| OEM-D-4W | Power steering pressure switch | digital_in | — | — | — | single_source |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-D-4A | SP-14V-1 | 0.85 | no route | ECU main power (+12V via main relay/ECR) | — | |
| W2 | OEM-D-4E | SP-14V-1 | 0.85 | no route | ECU main power (+12V via main relay/ECR) | — | |
| W3 | NEW-KEYON-1 | MAIN-R-COIL+ | 0.5 | no route | Relay coil positive (ignition-switched +12V) | — | |
| W4 | NEW-BATT-1 | MAIN-R-IN | 0.85 | no route | Relay contact input (battery + via main fuse) | — | |
| W5 | MAIN-R-COIL- | SP-GND-1 | 0.5 | no route | Relay coil negative (ECU low-side driver) | — | |
| W6 | MAIN-R-OUT | SPEEDUINO-PWR-12V | 0.85 | no route | Relay contact output (switched +12V bus) | — | |
| W7 | OEM-A-1AF | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W8 | OEM-A-1AJ | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W9 | OEM-A-1L | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W10 | SP-GND-1 | SPEEDUINO-A-10 | 0.85 | no route | Ground | — | |
| W11 | SP-GND-1 | SPEEDUINO-A-9 | 0.85 | no route | Ground | — | |
| W12 | OEM-A-1AB | SP-0V-1 | 0.5 | no route | Sensor ground | — | |
| W13 | OEM-A-1X | SP-0V-1 | 0.5 | no route | Sensor ground | — | |
| W14 | OEM-C-3AB | SP-0V-1 | 0.5 | no route | Sensor ground | — | |
| W15 | OEM-C-3S | SP-0V-1 | 0.5 | no route | Sensor ground (CAS) | — | |
| W16 | SP-0V-1 | SPEEDUINO-A-12 | 0.5 | no route | Ground | — | |
| W17 | SP-0V-1 | SPEEDUINO-A-23 | 0.5 | no route | Ground | — | |
| W18 | OEM-C-3A | SPEEDUINO-A-13 | 0.5 | no route | +5V sensor supply | — | |
| W19 | OEM-C-3R | SPEEDUINO-A-25 | 0.5 | no route | Crank position (CAS NE) | — | |
| W20 | OEM-C-3U | SPEEDUINO-A-24 | 0.5 | no route | Home position (CAS G) | — | |
| W21 | OEM-D-4AF | SPEEDUINO-A-7 | 0.5 | no route | Ignition front trailing | — | |
| W22 | OEM-D-4AJ | SPEEDUINO-A-34 | 0.5 | no route | Ignition rear trailing | — | |
| W23 | OEM-D-4AN | SPEEDUINO-A-33 | 0.5 | no route | Ignition leading (wasted spark) | — | |
| W24 | OEM-A-1Q | SPEEDUINO-A-1 | 0.5 | no route | Injector 1 (front primary) | — | |
| W25 | OEM-A-1U | SPEEDUINO-A-2 | 0.5 | no route | Injector 2 (rear primary) | — | |
| W26 | OEM-A-1Y | SPEEDUINO-A-3 | 0.5 | no route | Injector 3 (front secondary) | — | |
| W27 | OEM-A-1AC | SPEEDUINO-A-5 | 0.5 | no route | Injector 4 (rear secondary) | — | |
| W28 | OEM-D-4AH | SPEEDUINO-A-11 | 0.5 | no route | MAP sensor (PIM) | — | |
| W29 | OEM-C-3I | SPEEDUINO-A-22 | 0.5 | no route | Throttle position (TPS, full range) | — | |
| W30 | OEM-C-3W | SPEEDUINO-A-19 | 0.5 | no route | Coolant temperature (ECT) | — | |
| W31 | OEM-A-1H | SPEEDUINO-A-16 | 0.5 | no route | Cooling fan relay (low speed) | — | |
| W32 | OEM-D-4D | SPEEDUINO-A-15 | 0.5 | no route | Air pump clutch relay | — | |
| W33 | OEM-D-4F | SPEEDUINO-A-36 | 0.5 | no route | Fuel pump speed relay | — | |
| W34 | OEM-D-4G | SPEEDUINO-A-35 | 0.5 | no route | Fuel pump relay | — | |
| W35 | OEM-D-4I | SPEEDUINO-A-37 | 0.5 | no route | A/C relay | — | |
| W36 | OEM-D-4K | SPEEDUINO-A-38 | 0.5 | no route | Cooling fan relay (low speed) | — | |
| W37 | OEM-D-4M | SPEEDUINO-A-17 | 0.5 | no route | Tachometer output | — | |
| W38 | OEM-C-3D | SPEEDUINO-A-21 | 0.5 | no route | O2 sensor (narrowband) | — | |
| W39 | OEM-C-3T | SPEEDUINO-A-20 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W40 | OEM-D-4Q | SPEEDUINO-A-14 | 0.5 | no route | Vehicle speed sensor | — | |
| W41 | OEM-D-4AA | SPEEDUINO-A-18 | 0.5 | no route | Brake pedal 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 (7)
| Severity | Code | Subject | Message |
|---|---|---|---|
| warn | LOAD_UNKNOWN | SPEEDUINO-A-15 | SPEEDUINO-A-15 "Proto area 2 (fan)" drives OEM-D-4D Air pump clutch relay (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | SPEEDUINO-A-16 | SPEEDUINO-A-16 "Proto area 3 (fuel pump)" drives OEM-A-1H Cooling fan relay (low speed) (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | SPEEDUINO-A-35 | SPEEDUINO-A-35 "Boost" drives OEM-D-4G Fuel pump relay (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | SPEEDUINO-A-36 | SPEEDUINO-A-36 "Idle 2 (3-wire idle)" drives OEM-D-4F Fuel pump speed relay (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | SPEEDUINO-A-37 | SPEEDUINO-A-37 "PWM idle" drives OEM-D-4I A/C relay (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| warn | LOAD_UNKNOWN | SPEEDUINO-A-38 | SPEEDUINO-A-38 "VVT" drives OEM-D-4K Cooling fan relay (low speed) (load 0.2 A) but its current rating is unknown. Check the ECU manual. |
| info | UNMAPPED | OEM | 20 optional OEM pins are not mapped: OEM-A-1AA OMP stepper phase B1; OEM-A-1AE OMP stepper phase A1; OEM-A-1C Idle speed control (ISC) solenoid; OEM-A-1E Turbo charge control solenoid; OEM-A-1G Purge solenoid; OEM-A-1I Turbo charge relief solenoid; OEM-A-1K Turbo pre-control solenoid; OEM-A-1M Turbo control solenoid; OEM-A-1O Boost control solenoid; OEM-A-1S OMP stepper phase B2; OEM-A-1W OMP stepper phase A2; OEM-C-3G Fuel pressure regulator control (PRC) solenoid; OEM-C-3H OMP position sensor; OEM-C-3O Knock sensor; OEM-C-3V Fuel temperature; OEM-D-4C Start signal (STA); OEM-D-4L Cooling fan relay (high speed); OEM-D-4S Clutch switch; OEM-D-4V A/C request; OEM-D-4W Power steering pressure switch |
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-D-4B | Battery-constant (memory) feed of the stock ECU: the new ECU has no such input, so it is not needed. | mapping-proposal |
Notes
Fit check: needs add-on. Resolve these before building: - Oil metering pump stepper driver needed; not documented for this ECU - Sequential twin-turbo control unconfirmed for this ECU - No knock input; the stock knock sensor would be unused Auto-mapped by auto_map() from the library pin data on 2026-10-20. Review every wire against both manuals before building. Not wired: - OEM-D 4B: Battery constant (+12V): Speeduino Speeduino has no battery-constant memory input; not needed - OEM-C 3O: Knock sensor: no free knock input on Speeduino Speeduino - OEM-D 4L: Cooling fan relay (high speed): no free relay_control/low_side/heater_low_side/ls_hs/injector rated ≥ 0.2 A on Speeduino Speeduino - OEM-A 1C: Idle speed control (ISC) solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 1E: Turbo charge control solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 1G: Purge solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 1I: Turbo charge relief solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 1K: Turbo pre-control solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 1M: Turbo control solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 1O: Boost control solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-C 3G: Fuel pressure regulator control (PRC) solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-C 3V: Fuel temperature: no free thermistor/analog_0_5 on Speeduino Speeduino - OEM-C 3H: OMP position sensor: no free analog_0_5 on Speeduino Speeduino - OEM-D 4C: Start signal (STA): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-D 4S: Clutch switch: no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-D 4V: A/C request: no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-D 4W: Power steering pressure switch: no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-A 1AA: OMP stepper phase B1: no +/− pair in the pinout (multi-phase or half-documented motor); wire by hand - OEM-A 1AE: OMP stepper phase A1: no +/− pair in the pinout (multi-phase or half-documented motor); wire by hand - OEM-A 1S: OMP stepper phase B2: no +/− pair in the pinout (multi-phase or half-documented motor); wire by hand - OEM-A 1W: OMP stepper phase A2: no +/− pair in the pinout (multi-phase or half-documented motor); wire by hand
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | Emtron SL4/SL6/SL8 pinout pages | https://docs.emtronaustralia.com.au/engine-management/wiring/index.html | archive | 2026-10-05 | e52b3da9996a |
| 4 | vendor_doc | Haltech: RX7 FD Series 7-8 Nexus PnP adapter pinout (HT-186338) | https://www.haltech.com/wp-admin/admin-ajax.php?action=ht_get_file&id=681af8c0cc78f3b6860e615e&op=1 | — | — | — |
| 4 | vendor_doc | Speeduino Manual (08/04/25) — V0.4 board IDC40 pinout & features | https://speeduino.com/Speeduino_manual.pdf | archive | 2026-10-05 | 21806bd29ef0 |
| 4 | vendor_doc | Speeduino wiki — V0.4 board & wiring (12v input, switched power) | https://wiki.speeduino.com/en/boards/V04 | — | — | — |
| 3 | forum | rusEFI Mazda Miata 2002 engine wiring | https://github.com/rusefi/rusefi/wiki/Mazda-Miata-2002 | archive | 2026-10-05 | cc3cae670408 |
| 2 | forum | defreezemotorsport: MS3 FD3S 16-bit ECU pinout | https://defreezemotorsport.ru/doku.php?id=ms3:fd3s162 | — | — | — |