Honda NSX NA1 1991-2005 (C30A) → Speeduino Speeduino v0.4 (auto)
Honda NSX NA1 1991-2005 (C30A) — Speeduino — Speeduino
⚠ NOT CHECKED. Don't build from this.
Drawn by Michael Gnankou · Rev 0 · draft · 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 | draft · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | 7: read the Findings page before cutting any wire |
| Size of the job | 46 wires · 9 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-A-23 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | OEM-A-24 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-B-2 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | SP-GND-1 | SPEEDUINO-A-10 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | SP-GND-1 | SPEEDUINO-A-9 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-A-26 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-B-10 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | OEM-B-12 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | OEM-B-14 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | OEM-B-16 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-D-21 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-D-22 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | SP-0V-1 | SPEEDUINO-A-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | SP-0V-1 | SPEEDUINO-A-23 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-D-18 | SP-5V1-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | OEM-D-19 | SP-5V1-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-D-20 | SP-5V1-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | SP-5V1-1 | SPEEDUINO-A-13 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-B-15 | SPEEDUINO-A-25 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-B-13 | SPEEDUINO-A-27 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-B-11 | SPEEDUINO-A-24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-B-9 | SPEEDUINO-A-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-A-21 | SPEEDUINO-A-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-A-22 | SPEEDUINO-A-34 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-B-8 | SPEEDUINO-A-33 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-B-6 | SPEEDUINO-A-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-A-1 | SPEEDUINO-A-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-A-3 | SPEEDUINO-A-2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-A-5 | SPEEDUINO-A-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-A-2 | SPEEDUINO-A-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-A-4 | SPEEDUINO-A-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-A-6 | SPEEDUINO-A-2 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-D-17 | SPEEDUINO-A-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-D-11 | SPEEDUINO-A-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-D-13 | SPEEDUINO-A-19 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-A-8 | SPEEDUINO-A-16 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-A-15 | SPEEDUINO-A-15 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-A-18 | SPEEDUINO-A-36 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-A-7 | SPEEDUINO-A-35 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-A-10 | SPEEDUINO-A-37 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-A-12 | SPEEDUINO-A-38 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W42 | OEM-C-4 | SPEEDUINO-A-17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W43 | OEM-D-14 | SPEEDUINO-A-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W44 | OEM-D-15 | SPEEDUINO-A-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W45 | OEM-C-2 | SPEEDUINO-A-14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W46 | OEM-D-9 | 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 | SPEEDUINO-A-10 | SPEEDUINO-A-13 | open (OL) | power ground must not touch 5 V sensor reference | |
| 2 | SPEEDUINO-A-12 | SPEEDUINO-A-13 | open (OL) | sensor 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
OEM-5
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| F2 | Front VTEC pressure switch | — | — | — | — | — | — | — | — |
| F4 | Rear VTEC pressure switch | — | — | — | — | — | — | — | — |
| F5 | Front VTEC solenoid valve | — | — | — | — | — | — | — | — |
| F7 | Rear VTEC solenoid valve | — | — | — | — | — | — | — | — |
OEM-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Injector 1 | — | W27 | — | 0.5 | SPEEDUINO-A-1 | — | — | — |
| 10 | Front O2 sensor heater (HTCNTF) | — | W40 | — | 0.5 | SPEEDUINO-A-37 | — | — | — |
| 11 | EGR control solenoid | — | — | — | — | — | — | — | — |
| 12 | Rear O2 sensor heater (HTCNTR) | — | W41 | — | 0.5 | SPEEDUINO-A-38 | — | — | — |
| 13 | Check engine light (WARN) | — | — | — | — | — | — | — | — |
| 14 | Chamber volume control solenoid (BPS) | — | — | — | — | — | — | — | — |
| 15 | A/C clutch relay (ACC) | — | W37 | — | 0.5 | SPEEDUINO-A-15 | — | — | — |
| 18 | Radiator fan control (FANCNTR) | — | W38 | — | 0.5 | SPEEDUINO-A-36 | — | — | — |
| 2 | Injector 4 | — | W30 | — | 0.5 | SPEEDUINO-A-5 | — | — | — |
| 20 | EVAP purge cut-off solenoid (PGS) | — | — | — | — | — | — | — | — |
| 21 | Ignition coil 1 | — | W23 | — | 0.5 | SPEEDUINO-A-7 | — | — | — |
| 22 | Ignition coil 2 | — | W24 | — | 0.5 | SPEEDUINO-A-34 | — | — | — |
| 23 | Power ground (PG1) | — | W1 | — | 0.85 | SP-GND-1 | — | — | — |
| 24 | Power ground (PG2) | — | W2 | — | 0.85 | SP-GND-1 | — | — | — |
| 25 | ECU power (IGP1) | — | — | — | — | — | — | — | — |
| 26 | Sensor ground (LG1) | — | W6 | — | 0.5 | SP-0V-1 | — | — | — |
| 3 | Injector 2 | — | W28 | — | 0.5 | SPEEDUINO-A-2 | — | — | — |
| 4 | Injector 5 | — | W31 | — | 0.5 | SPEEDUINO-A-1 | — | — | — |
| 5 | Injector 3 | — | W29 | — | 0.5 | SPEEDUINO-A-3 | — | — | — |
| 6 | Injector 6 | — | W32 | — | 0.5 | SPEEDUINO-A-2 | — | — | — |
| 7 | Main relay | — | W39 | — | 0.5 | SPEEDUINO-A-35 | — | — | — |
| 8 | Fuel pump relay 2 (FLR2) | — | W36 | — | 0.5 | SPEEDUINO-A-16 | — | — | — |
| 9 | Idle air control valve (IACV) | — | — | — | — | — | — | — | — |
OEM-B
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 10 | CYL 2M — CYP sensor 2 return | — | W7 | — | 0.5 | SP-0V-1 | — | — | — |
| 11 | CYL 1P — CYP sensor 1 signal | — | W21 | — | 0.5 | SPEEDUINO-A-24 | — | — | — |
| 12 | CYL 1M — CYP sensor 1 return | — | W8 | — | 0.5 | SP-0V-1 | — | — | — |
| 13 | CRNK 2P — TDC sensor signal | — | W20 | — | 0.5 | SPEEDUINO-A-27 | — | — | — |
| 14 | CRNK 2M — TDC sensor return | — | W9 | — | 0.5 | SP-0V-1 | — | — | — |
| 15 | CRNK 1P — crank sensor signal | — | W19 | — | 0.5 | SPEEDUINO-A-25 | — | — | — |
| 16 | CRNK 1M — crank sensor return | — | W10 | — | 0.5 | SP-0V-1 | — | — | — |
| 2 | Chassis ground (LG2) | — | W3 | — | 0.85 | SP-GND-1 | — | — | — |
| 3 | Ignition coil 6 | — | — | — | — | — | — | — | — |
| 4 | Ignition coil 5 | — | — | — | — | — | — | — | — |
| 6 | Ignition coil 4 | — | W26 | — | 0.5 | SPEEDUINO-A-8 | — | — | — |
| 7 | Neutral switch (M/T) / gear position (A/T) | — | — | — | — | — | — | — | — |
| 8 | Ignition coil 3 | — | W25 | — | 0.5 | SPEEDUINO-A-33 | — | — | — |
| 9 | CYL 2P — CYP sensor 2 signal | — | W22 | — | 0.5 | SPEEDUINO-A-26 | — | — | — |
OEM-C
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | ECU power (IGP2) | — | — | — | — | — | — | — | — |
| 10 | Traction control | — | — | — | — | — | — | — | — |
| 11 | Starter switch (STS) | — | — | — | — | — | — | — | — |
| 12 | Traction control | — | — | — | — | — | — | — | — |
| 2 | Vehicle speed sensor (VSS) | — | W45 | — | 0.5 | SPEEDUINO-A-14 | — | — | — |
| 3 | A/C switch (ACS) | — | — | — | — | — | — | — | — |
| 4 | Tachometer output (NEP) | — | W42 | — | 0.5 | SPEEDUINO-A-17 | — | — | — |
| 5 | A/C pressure switch (PDSW) | — | — | — | — | — | — | — | — |
| 6 | Traction control | — | — | — | — | — | — | — | — |
| 7 | Clutch switch (M/T) | — | — | — | — | — | — | — | — |
| 8 | Traction control | — | — | — | — | — | — | — | — |
| 9 | Service check connector (SCS) | — | — | — | — | — | — | — | — |
OEM-D
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Battery backup (VBU) | — | — | — | — | — | — | — | — |
| 11 | Throttle position sensor (TPS) | — | W34 | — | 0.5 | SPEEDUINO-A-22 | — | — | — |
| 12 | EGR lift sensor (EGRL) | — | — | — | — | — | — | — | — |
| 13 | Engine coolant temperature (ECT) | — | W35 | — | 0.5 | SPEEDUINO-A-19 | — | — | — |
| 14 | Primary O2 sensor | — | W43 | — | 0.5 | SPEEDUINO-A-21 | — | — | — |
| 15 | Intake air temperature (IAT) | — | W44 | — | 0.5 | SPEEDUINO-A-20 | — | — | — |
| 16 | Secondary O2 sensor | — | — | — | — | — | — | — | — |
| 17 | MAP sensor | — | W33 | — | 0.5 | SPEEDUINO-A-11 | — | — | — |
| 18 | +5V sensor supply (VCC) | — | W15 | — | 0.5 | SP-5V1-1 | — | — | — |
| 19 | +5V sensor supply (VCC) | — | W16 | — | 0.5 | SP-5V1-1 | — | — | — |
| 20 | +5V sensor supply (VCC) | — | W17 | — | 0.5 | SP-5V1-1 | — | — | — |
| 21 | Sensor ground (SG) | — | W11 | — | 0.5 | SP-0V-1 | — | — | — |
| 22 | Sensor ground (SG) | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| 3 | Knock sensor — rear | — | — | — | — | — | — | — | — |
| 4 | Knock sensor — front | — | — | — | — | — | — | — | — |
| 5 | Traction control | — | — | — | — | — | — | — | — |
| 6 | Fuel pump voltage monitor (VFP) | — | — | — | — | — | — | — | — |
| 8 | Ignition timing adjuster (IGADJ) | — | — | — | — | — | — | — | — |
| 9 | Alternator FR signal | — | W46 | — | 0.5 | SPEEDUINO-A-18 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W6 | — | 0.5 | OEM-A-26 | — | — | — |
| 1 | — | — | W7 | — | 0.5 | OEM-B-10 | — | — | — |
| 1 | — | — | W8 | — | 0.5 | OEM-B-12 | — | — | — |
| 1 | — | — | W9 | — | 0.5 | OEM-B-14 | — | — | — |
| 1 | — | — | W10 | — | 0.5 | OEM-B-16 | — | — | — |
| 1 | — | — | W11 | — | 0.5 | OEM-D-21 | — | — | — |
| 1 | — | — | W12 | — | 0.5 | OEM-D-22 | — | — | — |
| 1 | — | — | W13 | — | 0.5 | SPEEDUINO-A-12 | — | — | — |
| 1 | — | — | W14 | — | 0.5 | SPEEDUINO-A-23 | — | — | — |
SP-5V1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W15 | — | 0.5 | OEM-D-18 | — | — | — |
| 1 | — | — | W16 | — | 0.5 | OEM-D-19 | — | — | — |
| 1 | — | — | W17 | — | 0.5 | OEM-D-20 | — | — | — |
| 1 | — | — | W18 | — | 0.5 | SPEEDUINO-A-13 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-A-23 | — | — | — |
| 1 | — | — | W2 | — | 0.85 | OEM-A-24 | — | — | — |
| 1 | — | — | W3 | — | 0.85 | OEM-B-2 | — | — | — |
| 1 | — | — | W4 | — | 0.85 | SPEEDUINO-A-10 | — | — | — |
| 1 | — | — | W5 | — | 0.85 | SPEEDUINO-A-9 | — | — | — |
SPEEDUINO-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Injector 1 | — | W27 | — | 0.5 | OEM-A-1 | — | — | — |
| 1 | Injector 1 | — | W31 | — | 0.5 | OEM-A-4 | — | — | — |
| 10 | Ground | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| 11 | MAP sensor (0-5V) | — | W33 | — | 0.5 | OEM-D-17 | — | — | — |
| 12 | Ground | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 13 | 5V | — | W18 | — | 0.5 | SP-5V1-1 | — | — | — |
| 14 | Proto area 1 (flex fuel) | — | W45 | — | 0.5 | OEM-C-2 | — | — | — |
| 15 | Proto area 2 (fan) | — | W37 | — | 0.5 | OEM-A-15 | — | — | — |
| 16 | Proto area 3 (fuel pump) | — | W36 | — | 0.5 | OEM-A-8 | — | — | — |
| 17 | Proto area 4 (tachometer) | — | W42 | — | 0.5 | OEM-C-4 | — | — | — |
| 18 | Proto area 5 (clutch) | — | W46 | — | 0.5 | OEM-D-9 | — | — | — |
| 19 | Coolant temp (CLT) | — | W35 | — | 0.5 | OEM-D-13 | — | — | — |
| 2 | Injector 2 | — | W28 | — | 0.5 | OEM-A-3 | — | — | — |
| 2 | Injector 2 | — | W32 | — | 0.5 | OEM-A-6 | — | — | — |
| 20 | Inlet air temp (IAT) | — | W44 | — | 0.5 | OEM-D-15 | — | — | — |
| 21 | O2 sensor | — | W43 | — | 0.5 | OEM-D-14 | — | — | — |
| 22 | TPS input | — | W34 | — | 0.5 | OEM-D-11 | — | — | — |
| 23 | Ground | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| 24 | Cam input / VR2+ | — | W21 | — | 0.5 | OEM-B-11 | — | — | — |
| 25 | Crank input / VR1+ | — | W19 | — | 0.5 | OEM-B-15 | — | — | — |
| 26 | VR2- | — | W22 | — | 0.5 | OEM-B-9 | — | — | — |
| 27 | VR1- | — | W20 | — | 0.5 | OEM-B-13 | — | — | — |
| 28 | 5V | — | — | — | — | — | — | — | — |
| 29 | Idle stepper 2B | — | — | — | — | — | — | — | — |
| 3 | Injector 3 | — | W29 | — | 0.5 | OEM-A-5 | — | — | — |
| 30 | Idle stepper 2A | — | — | — | — | — | — | — | — |
| 31 | Idle stepper 1A | — | — | — | — | — | — | — | — |
| 32 | Idle stepper 1B | — | — | — | — | — | — | — | — |
| 33 | Ignition 3 | — | W25 | — | 0.5 | OEM-B-8 | — | — | — |
| 34 | Ignition 2 | — | W24 | — | 0.5 | OEM-A-22 | — | — | — |
| 35 | Boost | — | W39 | — | 0.5 | OEM-A-7 | — | — | — |
| 36 | Idle 2 (3-wire idle) | — | W38 | — | 0.5 | OEM-A-18 | — | — | — |
| 37 | PWM idle | — | W40 | — | 0.5 | OEM-A-10 | — | — | — |
| 38 | VVT | — | W41 | — | 0.5 | OEM-A-12 | — | — | — |
| 5 | Injector 4 | — | W30 | — | 0.5 | OEM-A-2 | — | — | — |
| 7 | Ignition 1 | — | W23 | — | 0.5 | OEM-A-21 | — | — | — |
| 8 | Ignition 4 | — | W26 | — | 0.5 | OEM-B-6 | — | — | — |
| 9 | Ground | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-5-F2 | Front VTEC pressure switch | digital_in | — | — | — | single_source | |
| OEM-5-F4 | Rear VTEC pressure switch | digital_in | — | — | — | single_source | |
| OEM-5-F5 | Front VTEC solenoid valve | high_side_out | — | — | — | single_source | |
| OEM-5-F7 | Rear VTEC solenoid valve | high_side_out | — | — | — | single_source | |
| OEM-A-1 | Injector 1 | injector_out | SPEEDUINO-A-1 | Injector 1 | injector_out | single_source | |
| OEM-A-10 | Front O2 sensor heater (HTCNTF) | low_side_out | SPEEDUINO-A-37 | PWM idle | low_side_out | single_source | |
| OEM-A-11 | EGR control solenoid | low_side_out | — | — | — | single_source | |
| OEM-A-12 | Rear O2 sensor heater (HTCNTR) | low_side_out | SPEEDUINO-A-38 | VVT | low_side_out | single_source | |
| OEM-A-13 | Check engine light (WARN) | low_side_out | — | — | — | single_source | |
| OEM-A-14 | Chamber volume control solenoid (BPS) | low_side_out | — | — | — | single_source | |
| OEM-A-15 | A/C clutch relay (ACC) | low_side_out | SPEEDUINO-A-15 | Proto area 2 (fan) | low_side_out | single_source | |
| OEM-A-18 | Radiator fan control (FANCNTR) | low_side_out | SPEEDUINO-A-36 | Idle 2 (3-wire idle) | low_side_out | single_source | |
| OEM-A-2 | Injector 4 | injector_out | SPEEDUINO-A-5 | Injector 4 | injector_out | single_source | |
| OEM-A-20 | EVAP purge cut-off solenoid (PGS) | low_side_out | — | — | — | single_source | |
| OEM-A-21 | Ignition coil 1 | ignition_out | SPEEDUINO-A-7 | Ignition 1 | ignition_out | single_source | |
| OEM-A-22 | Ignition coil 2 | ignition_out | SPEEDUINO-A-34 | Ignition 2 | ignition_out | single_source | |
| OEM-A-23 | Power ground (PG1) | ground | SPEEDUINO-A-10 + SPEEDUINO-A-9 | Ground + Ground | ground | single_source | |
| OEM-A-24 | Power ground (PG2) | ground | SPEEDUINO-A-10 + SPEEDUINO-A-9 | Ground + Ground | ground | single_source | |
| OEM-A-25 | ECU power (IGP1) | power_in | — | — | — | single_source | |
| OEM-A-26 | Sensor ground (LG1) | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-A-3 | Injector 2 | injector_out | SPEEDUINO-A-2 | Injector 2 | injector_out | single_source | |
| OEM-A-4 | Injector 5 | injector_out | SPEEDUINO-A-1 | Injector 1 | injector_out | corroborated | |
| OEM-A-5 | Injector 3 | injector_out | SPEEDUINO-A-3 | Injector 3 | injector_out | single_source | |
| OEM-A-6 | Injector 6 | injector_out | SPEEDUINO-A-2 | Injector 2 | injector_out | single_source | |
| OEM-A-7 | Main relay | low_side_out | SPEEDUINO-A-35 | Boost | low_side_out | single_source | |
| OEM-A-8 | Fuel pump relay 2 (FLR2) | low_side_out | SPEEDUINO-A-16 | Proto area 3 (fuel pump) | low_side_out | single_source | |
| OEM-A-9 | Idle air control valve (IACV) | low_side_out | — | — | — | single_source | |
| OEM-B-10 | CYL 2M — CYP sensor 2 return | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-B-11 | CYL 1P — CYP sensor 1 signal | trigger_in | SPEEDUINO-A-24 | Cam input / VR2+ | trigger_in | single_source | |
| OEM-B-12 | CYL 1M — CYP sensor 1 return | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-B-13 | CRNK 2P — TDC sensor signal | trigger_in | SPEEDUINO-A-27 | VR1- | trigger_in | single_source | |
| OEM-B-14 | CRNK 2M — TDC sensor return | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-B-15 | CRNK 1P — crank sensor signal | trigger_in | SPEEDUINO-A-25 | Crank input / VR1+ | trigger_in | single_source | |
| OEM-B-16 | CRNK 1M — crank sensor return | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-B-2 | Chassis ground (LG2) | ground | SPEEDUINO-A-10 + SPEEDUINO-A-9 | Ground + Ground | ground | single_source | |
| OEM-B-3 | Ignition coil 6 | ignition_out | — | — | — | single_source | |
| OEM-B-4 | Ignition coil 5 | ignition_out | — | — | — | single_source | |
| OEM-B-6 | Ignition coil 4 | ignition_out | SPEEDUINO-A-8 | Ignition 4 | ignition_out | single_source | |
| OEM-B-7 | Neutral switch (M/T) / gear position (A/T) | digital_in | — | — | — | single_source | |
| OEM-B-8 | Ignition coil 3 | ignition_out | SPEEDUINO-A-33 | Ignition 3 | ignition_out | single_source | |
| OEM-B-9 | CYL 2P — CYP sensor 2 signal | trigger_in | SPEEDUINO-A-26 | VR2- | trigger_in | single_source | |
| OEM-C-1 | ECU power (IGP2) | power_in | — | — | — | single_source | |
| OEM-C-10 | Traction control | — | — | — | — | single_source | |
| OEM-C-11 | Starter switch (STS) | digital_in | — | — | — | single_source | |
| OEM-C-12 | Traction control | — | — | — | — | single_source | |
| OEM-C-2 | Vehicle speed sensor (VSS) | digital_in | SPEEDUINO-A-14 | Proto area 1 (flex fuel) | digital_in | single_source | |
| OEM-C-3 | A/C switch (ACS) | digital_in | — | — | — | single_source | |
| OEM-C-4 | Tachometer output (NEP) | tacho_out | SPEEDUINO-A-17 | Proto area 4 (tachometer) | tacho_out | single_source | |
| OEM-C-5 | A/C pressure switch (PDSW) | digital_in | — | — | — | single_source | |
| OEM-C-6 | Traction control | — | — | — | — | single_source | |
| OEM-C-7 | Clutch switch (M/T) | digital_in | — | — | — | single_source | |
| OEM-C-8 | Traction control | — | — | — | — | single_source | |
| OEM-C-9 | Service check connector (SCS) | digital_in | — | — | — | single_source | |
| OEM-D-1 | Battery backup (VBU) | power_in | — | — | — | single_source | |
| OEM-D-11 | Throttle position sensor (TPS) | analog_in | SPEEDUINO-A-22 | TPS input | analog_in | single_source | |
| OEM-D-12 | EGR lift sensor (EGRL) | analog_in | — | — | — | single_source | |
| OEM-D-13 | Engine coolant temperature (ECT) | temp_in | SPEEDUINO-A-19 | Coolant temp (CLT) | temp_in | single_source | |
| OEM-D-14 | Primary O2 sensor | lambda_nb_in | SPEEDUINO-A-21 | O2 sensor | lambda_nb_in | single_source | |
| OEM-D-15 | Intake air temperature (IAT) | temp_in | SPEEDUINO-A-20 | Inlet air temp (IAT) | temp_in | single_source | |
| OEM-D-16 | Secondary O2 sensor | lambda_nb_in | — | — | — | single_source | |
| OEM-D-17 | MAP sensor | analog_in | SPEEDUINO-A-11 | MAP sensor (0-5V) | analog_in | single_source | |
| OEM-D-18 | +5V sensor supply (VCC) | vref | SPEEDUINO-A-13 | 5V | vref | single_source | |
| OEM-D-19 | +5V sensor supply (VCC) | vref | SPEEDUINO-A-13 | 5V | vref | single_source | |
| OEM-D-20 | +5V sensor supply (VCC) | vref | SPEEDUINO-A-13 | 5V | vref | single_source | |
| OEM-D-21 | Sensor ground (SG) | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-D-22 | Sensor ground (SG) | sensor_ground | SPEEDUINO-A-12 + SPEEDUINO-A-23 | Ground + Ground | sensor_ground | single_source | |
| OEM-D-3 | Knock sensor — rear | knock_in | — | — | — | single_source | |
| OEM-D-4 | Knock sensor — front | knock_in | — | — | — | single_source | |
| OEM-D-5 | Traction control | — | — | — | — | single_source | |
| OEM-D-6 | Fuel pump voltage monitor (VFP) | — | — | — | — | corroborated | |
| OEM-D-8 | Ignition timing adjuster (IGADJ) | digital_in | — | — | — | single_source | |
| OEM-D-9 | Alternator FR signal | digital_in | SPEEDUINO-A-18 | Proto area 5 (clutch) | digital_in | single_source |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-A-23 | SP-GND-1 | 0.85 | no route | Power ground (PG1) | — | |
| W2 | OEM-A-24 | SP-GND-1 | 0.85 | no route | Power ground (PG2) | — | |
| W3 | OEM-B-2 | SP-GND-1 | 0.85 | no route | Chassis ground (LG2) | — | |
| W4 | SP-GND-1 | SPEEDUINO-A-10 | 0.85 | no route | Ground | — | |
| W5 | SP-GND-1 | SPEEDUINO-A-9 | 0.85 | no route | Ground | — | |
| W6 | OEM-A-26 | SP-0V-1 | 0.5 | no route | Sensor ground (LG1) | — | |
| W7 | OEM-B-10 | SP-0V-1 | 0.5 | no route | CYL 2M — CYP sensor 2 return | — | |
| W8 | OEM-B-12 | SP-0V-1 | 0.5 | no route | CYL 1M — CYP sensor 1 return | — | |
| W9 | OEM-B-14 | SP-0V-1 | 0.5 | no route | CRNK 2M — TDC sensor return | — | |
| W10 | OEM-B-16 | SP-0V-1 | 0.5 | no route | CRNK 1M — crank sensor return | — | |
| W11 | OEM-D-21 | SP-0V-1 | 0.5 | no route | Sensor ground (SG) | — | |
| W12 | OEM-D-22 | SP-0V-1 | 0.5 | no route | Sensor ground (SG) | — | |
| W13 | SP-0V-1 | SPEEDUINO-A-12 | 0.5 | no route | Ground | — | |
| W14 | SP-0V-1 | SPEEDUINO-A-23 | 0.5 | no route | Ground | — | |
| W15 | OEM-D-18 | SP-5V1-1 | 0.5 | no route | +5V sensor supply (VCC) | — | |
| W16 | OEM-D-19 | SP-5V1-1 | 0.5 | no route | +5V sensor supply (VCC) | — | |
| W17 | OEM-D-20 | SP-5V1-1 | 0.5 | no route | +5V sensor supply (VCC) | — | |
| W18 | SP-5V1-1 | SPEEDUINO-A-13 | 0.5 | no route | 5V | — | |
| W19 | OEM-B-15 | SPEEDUINO-A-25 | 0.5 | no route | CRNK 1P — crank sensor signal | — | |
| W20 | OEM-B-13 | SPEEDUINO-A-27 | 0.5 | no route | CRNK 2P — TDC sensor signal | — | |
| W21 | OEM-B-11 | SPEEDUINO-A-24 | 0.5 | no route | CYL 1P — CYP sensor 1 signal | — | |
| W22 | OEM-B-9 | SPEEDUINO-A-26 | 0.5 | no route | CYL 2P — CYP sensor 2 signal | — | |
| W23 | OEM-A-21 | SPEEDUINO-A-7 | 0.5 | no route | Ignition coil 1 | — | |
| W24 | OEM-A-22 | SPEEDUINO-A-34 | 0.5 | no route | Ignition coil 2 | — | |
| W25 | OEM-B-8 | SPEEDUINO-A-33 | 0.5 | no route | Ignition coil 3 | — | |
| W26 | OEM-B-6 | SPEEDUINO-A-8 | 0.5 | no route | Ignition coil 4 | — | |
| W27 | OEM-A-1 | SPEEDUINO-A-1 | 0.5 | no route | Injector 1 | — | |
| W28 | OEM-A-3 | SPEEDUINO-A-2 | 0.5 | no route | Injector 2 | — | |
| W29 | OEM-A-5 | SPEEDUINO-A-3 | 0.5 | no route | Injector 3 | — | |
| W30 | OEM-A-2 | SPEEDUINO-A-5 | 0.5 | no route | Injector 4 | — | |
| W31 | OEM-A-4 | SPEEDUINO-A-1 | 0.5 | no route | Injector 5 | — | |
| W32 | OEM-A-6 | SPEEDUINO-A-2 | 0.5 | no route | Injector 6 | — | |
| W33 | OEM-D-17 | SPEEDUINO-A-11 | 0.5 | no route | MAP sensor | — | |
| W34 | OEM-D-11 | SPEEDUINO-A-22 | 0.5 | no route | Throttle position sensor (TPS) | — | |
| W35 | OEM-D-13 | SPEEDUINO-A-19 | 0.5 | no route | Engine coolant temperature (ECT) | — | |
| W36 | OEM-A-8 | SPEEDUINO-A-16 | 0.5 | no route | Fuel pump relay 2 (FLR2) | — | |
| W37 | OEM-A-15 | SPEEDUINO-A-15 | 0.5 | no route | A/C clutch relay (ACC) | — | |
| W38 | OEM-A-18 | SPEEDUINO-A-36 | 0.5 | no route | Radiator fan control (FANCNTR) | — | |
| W39 | OEM-A-7 | SPEEDUINO-A-35 | 0.5 | no route | Main relay | — | |
| W40 | OEM-A-10 | SPEEDUINO-A-37 | 0.5 | no route | Front O2 sensor heater (HTCNTF) | — | |
| W41 | OEM-A-12 | SPEEDUINO-A-38 | 0.5 | no route | Rear O2 sensor heater (HTCNTR) | — | |
| W42 | OEM-C-4 | SPEEDUINO-A-17 | 0.5 | no route | Tachometer output (NEP) | — | |
| W43 | OEM-D-14 | SPEEDUINO-A-21 | 0.5 | no route | Primary O2 sensor | — | |
| W44 | OEM-D-15 | SPEEDUINO-A-20 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W45 | OEM-C-2 | SPEEDUINO-A-14 | 0.5 | no route | Vehicle speed sensor (VSS) | — | |
| W46 | OEM-D-9 | SPEEDUINO-A-18 | 0.5 | no route | Alternator FR signal | — |
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 (8)
| Severity | Code | Subject | Message |
|---|---|---|---|
| error | INJECTOR_BALLAST | Speeduino | The C30A injectors (NSX fuel injector) are low-impedance, but Speeduino drives saturated (high-Z) injectors only. Add a ballast resistor pack in series with each injector, or use an ECU with low-Z / peak-and-hold injector drivers. |
| error | NET_MERGED | OEM-A-1 + OEM-A-4 + SPEEDUINO-A-1 | 2 different OEM functions share one net: OEM-A-1 Injector 1; OEM-A-4 Injector 5 |
| error | NET_MERGED | OEM-A-3 + OEM-A-6 + SPEEDUINO-A-2 | 2 different OEM functions share one net: OEM-A-3 Injector 2; OEM-A-6 Injector 6 |
| error | REQUIRED_UNMAPPED | OEM-A-25 | Required OEM function "ECU power (IGP1)" (power_in) is not connected to the new ECU. |
| error | REQUIRED_UNMAPPED | OEM-B-3 | Required OEM function "Ignition coil 6" (ignition_out) is not connected to the new ECU. |
| error | REQUIRED_UNMAPPED | OEM-B-4 | Required OEM function "Ignition coil 5" (ignition_out) is not connected to the new ECU. |
| error | REQUIRED_UNMAPPED | OEM-C-1 | Required OEM function "ECU power (IGP2)" (power_in) is not connected to the new ECU. |
| info | UNMAPPED | OEM | 26 optional OEM pins are not mapped: OEM-5-F2 Front VTEC pressure switch; OEM-5-F4 Rear VTEC pressure switch; OEM-5-F5 Front VTEC solenoid valve; OEM-5-F7 Rear VTEC solenoid valve; OEM-A-11 EGR control solenoid; OEM-A-13 Check engine light (WARN); OEM-A-14 Chamber volume control solenoid (BPS); OEM-A-20 EVAP purge cut-off solenoid (PGS); OEM-A-9 Idle air control valve (IACV); OEM-B-7 Neutral switch (M/T) / gear position (A/T); OEM-C-10 Traction control; OEM-C-11 Starter switch (STS); OEM-C-12 Traction control; OEM-C-3 A/C switch (ACS); OEM-C-5 A/C pressure switch (PDSW); OEM-C-6 Traction control; OEM-C-7 Clutch switch (M/T); OEM-C-8 Traction control; OEM-C-9 Service check connector (SCS); OEM-D-12 EGR lift sensor (EGRL); OEM-D-16 Secondary O2 sensor; OEM-D-3 Knock sensor — rear; OEM-D-4 Knock sensor — front; OEM-D-5 Traction control; OEM-D-6 Fuel pump voltage monitor (VFP); OEM-D-8 Ignition timing adjuster (IGADJ) |
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-D-1 | 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: unconfirmed. Confirm these before building: - Trigger pattern for Honda C30A not found in the ECU's docs (Decoder list Honda = D17 (complete) / K20/K24 (in dev) / J30/J32 (in dev) — no C30A/C32B/NSX) - No knock input; the stock knock sensor would be unused - Only 4 ignition outputs for 6 cylinders: wasted spark (pair coils per firing order) - Only 4 injector outputs for 6 injectors: batch / semi-sequential injection Auto-mapped by auto_map() from the library pin data on 2026-10-11. Review every wire against both manuals before building. Open items: - Main-relay feed: no ecu_main_power pin on the stock or the new ECU - OEM-B 4: Ignition coil 5: no free ignition output on Speeduino Speeduino - OEM-B 3: Ignition coil 6: no free ignition output on Speeduino Speeduino - OEM-A 25: ECU power (IGP1): no rule for class ecu_main_power; wire by hand - OEM-C 1: ECU power (IGP2): no rule for class ecu_main_power; wire by hand Not wired: - OEM-D 1: Battery backup (VBU): Speeduino Speeduino has no battery-constant input; not needed - OEM-D 4: Knock sensor — front: no free knock input on Speeduino Speeduino - OEM-D 3: Knock sensor — rear: no free knock input on Speeduino Speeduino - OEM-5 F5: Front VTEC solenoid valve: no free high_side/ls_hs on Speeduino Speeduino - OEM-5 F7: Rear VTEC solenoid valve: no free high_side/ls_hs on Speeduino Speeduino - OEM-A 11: EGR control solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 13: Check engine light (WARN): no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 14: Chamber volume control solenoid (BPS): no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 20: EVAP purge cut-off solenoid (PGS): no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-A 9: Idle air control valve (IACV): no free low_side/relay_control/heater_low_side/ls_hs/injector on Speeduino Speeduino - OEM-D 16: Secondary O2 sensor: no free o2_narrowband/analog_0_5 on Speeduino Speeduino - OEM-D 12: EGR lift sensor (EGRL): no free analog_0_5 on Speeduino Speeduino - OEM-5 F2: Front VTEC pressure switch: no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-5 F4: Rear VTEC pressure switch: no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-B 7: Neutral switch (M/T) / gear position (A/T): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-C 11: Starter switch (STS): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-C 3: A/C switch (ACS): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-C 5: A/C pressure switch (PDSW): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-C 7: Clutch switch (M/T): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-C 9: Service check connector (SCS): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-D 8: Ignition timing adjuster (IGADJ): no free switch_in/frequency_in/analog_0_5 on Speeduino Speeduino - OEM-C 10: Traction control: not classified in the library; wire by hand - OEM-C 12: Traction control: not classified in the library; wire by hand - OEM-C 6: Traction control: not classified in the library; wire by hand - OEM-C 8: Traction control: not classified in the library; wire by hand - OEM-D 5: Traction control: not classified in the library; wire by hand - OEM-D 6: Fuel pump voltage monitor (VFP): not classified in the library; wire by hand
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | AEM EMS 30-1042 (Series 1) plug-and-play install manual — 1991-94 NSX | https://fancy-craft.firebaseapp.com/NSX/report/ecu/EMS_-_30-1042.pdf | archive | 2026-10-05 | 0cad10bc64b5 |
| 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 |
| 3 | vendor_doc | dodo-upgrades: Honda OBD1 V6 ECU pinout | https://dodo-upgrades.nl/index.php/obd1-v6-pinouts/ | archive | 2026-10-05 | f9539af28904 |