MX-5 Miata NA6 1990-93 (B6-ZE, 1.6) → AMP EFI MS3Pro Ultimate (auto)
MX-5 Miata NA6 1990-93 (B6-ZE, 1.6) — AMP EFI — MS3Pro Ultimate
Drawn by Michael Gnankou · Rev 0 · proposal · 2026-10-08
Before you start
| Status | proposal · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | none |
| Size of the job | 44 wires · 8 connectors · 2 part lines |
| Tools | Crimp and extraction tools for each terminal family (see Connectors) · wire strippers · multimeter · heat gun + heat-shrink |
| Order of work | 1. Check every part against the parts list. 2. Cut and label every wire (labels: Export → Wire labels). 3. Crimp and pin connector by connector, ticking the build checklist. 4. Run the bench test with nothing plugged in and the battery disconnected. 5. Only then connect the ECU and power up. |
Build checklist
Tick each box as you go. Continuity: meter from end to end, expect under 1 Ω.
| Wire | From | To | Gauge | Colour | Cut | Label | Crimp A | Crimp B | Pin A | Pin B | Continuity |
|---|---|---|---|---|---|---|---|---|---|---|---|
| W1 | OEM-1-B | SP-14V-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | SP-14V-1 | MS3PROULTIMA-A-35 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | OEM-1-A | MS3PROULTIMA-C-23 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | OEM-2-A | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | OEM-2-B | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-2-C | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-2-D | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | SP-GND-1 | MS3PROULTIMA-A-13 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-GND-1 | MS3PROULTIMA-B-18 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-GND-1 | MS3PROULTIMA-B-3 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | SP-GND-1 | MS3PROULTIMA-B-5 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | SP-GND-1 | MS3PROULTIMA-B-7 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | SP-GND-1 | MS3PROULTIMA-B-9 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-2-F | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | SP-0V-1 | MS3PROULTIMA-A-16 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | SP-0V-1 | MS3PROULTIMA-A-18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | SP-0V-1 | MS3PROULTIMA-C-17 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | SP-0V-1 | MS3PROULTIMA-C-18 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | SP-0V-1 | MS3PROULTIMA-C-19 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | SP-0V-1 | MS3PROULTIMA-C-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | SP-0V-1 | MS3PROULTIMA-C-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-2-K | MS3PROULTIMA-A-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-2-E | MS3PROULTIMA-A-6 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | SP-0V-1 | MS3PROULTIMA-A-15 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-2-G | MS3PROULTIMA-A-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | SP-0V-1 | MS3PROULTIMA-A-27 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-1-G | MS3PROULTIMA-B-13 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-1-H | MS3PROULTIMA-B-14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-2-U | MS3PROULTIMA-A-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-2-V | MS3PROULTIMA-A-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-2-Y | MS3PROULTIMA-B-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-2-Z | MS3PROULTIMA-B-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-1-E | MS3PROULTIMA-A-14 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-2-I | MS3PROULTIMA-A-24 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-2-O | MS3PROULTIMA-A-19 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W36 | OEM-2-N | MS3PROULTIMA-A-25 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W37 | OEM-2-Q | MS3PROULTIMA-A-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W38 | OEM-2-P | MS3PROULTIMA-A-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W39 | OEM-1-C | MS3PROULTIMA-A-32 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W40 | OEM-1-N | MS3PROULTIMA-B-20 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W41 | OEM-1-P | MS3PROULTIMA-B-29 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W42 | OEM-1-Q | MS3PROULTIMA-C-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W43 | OEM-1-V | MS3PROULTIMA-C-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W44 | OEM-2-L | MS3PROULTIMA-B-28 | 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 | MS3PROULTIMA-A-35 | MS3PROULTIMA-A-13 | open (OL) | +12 V supply must not touch power ground | |
| 2 | MS3PROULTIMA-A-35 | MS3PROULTIMA-A-15 | open (OL) | +12 V supply must not touch sensor ground | |
| 3 | MS3PROULTIMA-C-23 | MS3PROULTIMA-A-13 | open (OL) | +12 V supply must not touch power ground | |
| 4 | MS3PROULTIMA-C-23 | MS3PROULTIMA-A-15 | open (OL) | +12 V supply must not touch sensor ground | |
| 5 | MS3PROULTIMA-A-13 | MS3PROULTIMA-A-8 | open (OL) | power ground must not touch 5 V sensor reference | |
| 6 | MS3PROULTIMA-A-15 | MS3PROULTIMA-A-8 | open (OL) | sensor ground must not touch 5 V sensor reference | |
| 7 | MS3PROULTIMA-A-35 | MS3PROULTIMA-A-8 | open (OL) | +12 V supply must not touch 5 V sensor reference | |
| 8 | MS3PROULTIMA-C-23 | MS3PROULTIMA-A-8 | open (OL) | +12 V supply must not touch 5 V sensor reference |
Revisions
| Rev | Label | By | Date |
|---|---|---|---|
| No revisions yet. | |||
Schematic
Connectors
MS3PROULTIMA-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | High current out 1 | — | — | — | — | — | — | — | — |
| 10 | MAT in | — | W37 | — | 0.5 | OEM-2-Q | — | — | — |
| 11 | CLT in | — | W38 | — | 0.5 | OEM-2-P | — | — | — |
| 12 | Analog In 6 | — | — | — | — | — | — | — | — |
| 13 | Power ground | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| 14 | PWM / Idle Out 1 | — | W33 | — | 0.5 | OEM-1-E | — | — | — |
| 15 | CKP− | — | W24 | — | 0.5 | SP-0V-1 | — | — | — |
| 16 | Logic ground | — | W15 | — | 0.5 | SP-0V-1 | — | — | — |
| 17 | Analog In 7 | — | — | — | — | — | — | — | — |
| 18 | Sensor return | — | W16 | — | 0.5 | SP-0V-1 | — | — | — |
| 19 | Analog in 1 | — | W35 | — | 0.5 | OEM-2-O | — | — | — |
| 2 | High current out 2 | — | — | — | — | — | — | — | — |
| 20 | Analog in 2 | — | — | — | — | — | — | — | — |
| 21 | Analog in 3 | — | — | — | — | — | — | — | — |
| 22 | Analog In 4 | — | — | — | — | — | — | — | — |
| 23 | Analog In 5 | — | — | — | — | — | — | — | — |
| 24 | Tach out | — | W34 | — | 0.5 | OEM-2-I | — | — | — |
| 25 | O2 in | — | W36 | — | 0.5 | OEM-2-N | — | — | — |
| 26 | CMP+ | — | W25 | — | 0.5 | OEM-2-G | — | — | — |
| 27 | CMP− | — | W26 | — | 0.5 | SP-0V-1 | — | — | — |
| 28 | Fuel pump relay out | — | — | — | — | — | — | — | — |
| 29 | PWM out 2 | — | — | — | — | — | — | — | — |
| 3 | Injector out J | — | W29 | — | 0.5 | OEM-2-U | — | — | — |
| 30 | PWM out 3 | — | — | — | — | — | — | — | — |
| 31 | Knock in 1 | — | — | — | — | — | — | — | — |
| 32 | Digital switched in 1 | — | W39 | — | 0.5 | OEM-1-C | — | — | — |
| 33 | CAN L | — | — | — | — | — | — | — | — |
| 34 | CAN H | — | — | — | — | — | — | — | — |
| 35 | 12V+ switched power in | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| 4 | Injector out I | — | W30 | — | 0.5 | OEM-2-V | — | — | — |
| 5 | High current out 3 | — | — | — | — | — | — | — | — |
| 6 | CKP+ | — | W23 | — | 0.5 | OEM-2-E | — | — | — |
| 7 | Knock In 2 | — | — | — | — | — | — | — | — |
| 8 | 5V+ VREF out 1 | — | W22 | — | 0.5 | OEM-2-K | — | — | — |
| 9 | TPS in | — | — | — | — | — | — | — | — |
MS3PROULTIMA-B
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | Injector out A | — | W31 | — | 0.5 | OEM-2-Y | — | — | — |
| 10 | Injector out F | — | W32 | — | 0.5 | OEM-2-Z | — | — | — |
| 11 | Injector out G | — | — | — | — | — | — | — | — |
| 12 | Injector out H | — | — | — | — | — | — | — | — |
| 13 | Spark out G | — | W27 | — | 0.5 | OEM-1-G | — | — | — |
| 14 | Spark out E | — | W28 | — | 0.5 | OEM-1-H | — | — | — |
| 15 | Spark out C | — | — | — | — | — | — | — | — |
| 16 | Spark out H | — | — | — | — | — | — | — | — |
| 17 | Digital frequency in 2 | — | — | — | — | — | — | — | — |
| 18 | Ground | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
| 19 | Digital switched 12V in | — | — | — | — | — | — | — | — |
| 2 | Injector out B | — | — | — | — | — | — | — | — |
| 20 | Digital switched in 2 | — | W40 | — | 0.5 | OEM-1-N | — | — | — |
| 21 | Digital frequency in 3 | — | — | — | — | — | — | — | — |
| 22 | Digital Frequency in 3 VR+ | — | — | — | — | — | — | — | — |
| 23 | Digital Frequency In 3 VR− | — | — | — | — | — | — | — | — |
| 24 | Spark out F | — | — | — | — | — | — | — | — |
| 25 | Spark out B | — | — | — | — | — | — | — | — |
| 26 | Spark out D | — | — | — | — | — | — | — | — |
| 27 | Spark out A | — | — | — | — | — | — | — | — |
| 28 | Digital frequency in 1 | — | W44 | — | 0.5 | OEM-2-L | — | — | — |
| 29 | Digital switched in 3 | — | W41 | — | 0.5 | OEM-1-P | — | — | — |
| 3 | Ground | — | W10 | — | 0.85 | SP-GND-1 | — | — | — |
| 30 | Stepper IAC out 1B | — | — | — | — | — | — | — | — |
| 31 | Stepper IAC out 1A | — | — | — | — | — | — | — | — |
| 32 | Stepper IAC out 2A | — | — | — | — | — | — | — | — |
| 33 | Stepper IAC out 2B | — | — | — | — | — | — | — | — |
| 34 | Digital Frequency in 1 VR+ | — | — | — | — | — | — | — | — |
| 35 | Digital Frequency in 1 VR− | — | — | — | — | — | — | — | — |
| 4 | Injector out C | — | — | — | — | — | — | — | — |
| 5 | Ground | — | W11 | — | 0.85 | SP-GND-1 | — | — | — |
| 6 | Injector out D | — | — | — | — | — | — | — | — |
| 7 | Ground | — | W12 | — | 0.85 | SP-GND-1 | — | — | — |
| 8 | Injector out E | — | — | — | — | — | — | — | — |
| 9 | Ground | — | W13 | — | 0.85 | SP-GND-1 | — | — | — |
MS3PROULTIMA-C
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | PWM out 5 | — | — | — | — | — | — | — | — |
| 10 | Digital switched in 5 | — | W43 | — | 0.5 | OEM-1-V | — | — | — |
| 11 | Digital switched in 4 | — | W42 | — | 0.5 | OEM-1-Q | — | — | — |
| 12 | Digital I/O 5 | — | — | — | — | — | — | — | — |
| 13 | Digital I/O 3 | — | — | — | — | — | — | — | — |
| 14 | Digital I/O 1 | — | — | — | — | — | — | — | — |
| 15 | 5V+ VREF out 2 | — | — | — | — | — | — | — | — |
| 16 | Fuel only battery 12V+ | — | — | — | — | — | — | — | — |
| 17 | Sensor return | — | W17 | — | 0.5 | SP-0V-1 | — | — | — |
| 18 | Sensor return | — | W18 | — | 0.5 | SP-0V-1 | — | — | — |
| 19 | Sensor return | — | W19 | — | 0.5 | SP-0V-1 | — | — | — |
| 2 | PWM out 4 | — | — | — | — | — | — | — | — |
| 20 | Sensor return | — | W20 | — | 0.5 | SP-0V-1 | — | — | — |
| 21 | Sensor return | — | W21 | — | 0.5 | SP-0V-1 | — | — | — |
| 22 | 5V+ VREF out 1 | — | — | — | — | — | — | — | — |
| 23 | Keep alive power | — | W3 | — | 0.85 | OEM-1-A | — | — | — |
| 3 | Digital out 2 | — | — | — | — | — | — | — | — |
| 4 | Digital out 1 | — | — | — | — | — | — | — | — |
| 5 | Digital I/O 4 | — | — | — | — | — | — | — | — |
| 6 | Digital I/O 2 | — | — | — | — | — | — | — | — |
| 7 | Analog in 8 | — | — | — | — | — | — | — | — |
| 8 | 5V+ VREF out 2 | — | — | — | — | — | — | — | — |
| 9 | Fuel only coil negative | — | — | — | — | — | — | — | — |
OEM-1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Constant +12V | — | W3 | — | 0.85 | MS3PROULTIMA-C-23 | — | — | — |
| B | ECU power +14V (main relay) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| C | Start signal | — | W39 | — | 0.5 | MS3PROULTIMA-A-32 | — | — | — |
| E | Malfunction indicator lamp (MIL) | — | W33 | — | 0.5 | MS3PROULTIMA-A-14 | — | — | — |
| G | Ignition 1 (coils 1+4, wasted spark) | — | W27 | — | 0.5 | MS3PROULTIMA-B-13 | — | — | — |
| H | Ignition 2 (coils 2+3, wasted spark) | — | W28 | — | 0.5 | MS3PROULTIMA-B-14 | — | — | — |
| N | Wide-open throttle switch | — | W40 | — | 0.5 | MS3PROULTIMA-B-20 | — | — | — |
| P | Power steering pressure switch | — | W41 | — | 0.5 | MS3PROULTIMA-B-29 | — | — | — |
| Q | A/C request | — | W42 | — | 0.5 | MS3PROULTIMA-C-11 | — | — | — |
| V | Neutral/clutch switch | — | W43 | — | 0.5 | MS3PROULTIMA-C-10 | — | — | — |
OEM-2
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Power ground | — | W4 | — | 0.85 | SP-GND-1 | — | — | — |
| B | Power ground | — | W5 | — | 0.85 | SP-GND-1 | — | — | — |
| C | Power ground | — | W6 | — | 0.85 | SP-GND-1 | — | — | — |
| D | Power ground | — | W7 | — | 0.85 | SP-GND-1 | — | — | — |
| E | Crank position (CAS NE) | — | W23 | — | 0.5 | MS3PROULTIMA-A-6 | — | — | — |
| F | AFM ground | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| G | Cam position (CAS G) | — | W25 | — | 0.5 | MS3PROULTIMA-A-26 | — | — | — |
| I | Tachometer output | — | W34 | — | 0.5 | MS3PROULTIMA-A-24 | — | — | — |
| K | +5V sensor supply | — | W22 | — | 0.5 | MS3PROULTIMA-A-8 | — | — | — |
| L | Idle switch (TPS) | — | W44 | — | 0.5 | MS3PROULTIMA-B-28 | — | — | — |
| N | O2 sensor | — | W36 | — | 0.5 | MS3PROULTIMA-A-25 | — | — | — |
| O | Air flow meter (AFM) | — | W35 | — | 0.5 | MS3PROULTIMA-A-19 | — | — | — |
| P | Intake air temperature (IAT) | — | W38 | — | 0.5 | MS3PROULTIMA-A-11 | — | — | — |
| Q | Coolant temperature (ECT) | — | W37 | — | 0.5 | MS3PROULTIMA-A-10 | — | — | — |
| U | Injector 1 | — | W29 | — | 0.5 | MS3PROULTIMA-A-3 | — | — | — |
| V | Injector 2 | — | W30 | — | 0.5 | MS3PROULTIMA-A-4 | — | — | — |
| Y | Injector 3 | — | W31 | — | 0.5 | MS3PROULTIMA-B-1 | — | — | — |
| Z | Injector 4 | — | W32 | — | 0.5 | MS3PROULTIMA-B-10 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W14 | — | 0.5 | OEM-2-F | — | — | — |
| 1 | — | — | W15 | — | 0.5 | MS3PROULTIMA-A-16 | — | — | — |
| 1 | — | — | W16 | — | 0.5 | MS3PROULTIMA-A-18 | — | — | — |
| 1 | — | — | W17 | — | 0.5 | MS3PROULTIMA-C-17 | — | — | — |
| 1 | — | — | W18 | — | 0.5 | MS3PROULTIMA-C-18 | — | — | — |
| 1 | — | — | W19 | — | 0.5 | MS3PROULTIMA-C-19 | — | — | — |
| 1 | — | — | W20 | — | 0.5 | MS3PROULTIMA-C-20 | — | — | — |
| 1 | — | — | W21 | — | 0.5 | MS3PROULTIMA-C-21 | — | — | — |
| 1 | — | — | W24 | — | 0.5 | MS3PROULTIMA-A-15 | — | — | — |
| 1 | — | — | W26 | — | 0.5 | MS3PROULTIMA-A-27 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-1-B | — | — | — |
| 1 | — | — | W2 | — | 0.85 | MS3PROULTIMA-A-35 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W4 | — | 0.85 | OEM-2-A | — | — | — |
| 1 | — | — | W5 | — | 0.85 | OEM-2-B | — | — | — |
| 1 | — | — | W6 | — | 0.85 | OEM-2-C | — | — | — |
| 1 | — | — | W7 | — | 0.85 | OEM-2-D | — | — | — |
| 1 | — | — | W8 | — | 0.85 | MS3PROULTIMA-A-13 | — | — | — |
| 1 | — | — | W9 | — | 0.85 | MS3PROULTIMA-B-18 | — | — | — |
| 1 | — | — | W10 | — | 0.85 | MS3PROULTIMA-B-3 | — | — | — |
| 1 | — | — | W11 | — | 0.85 | MS3PROULTIMA-B-5 | — | — | — |
| 1 | — | — | W12 | — | 0.85 | MS3PROULTIMA-B-7 | — | — | — |
| 1 | — | — | W13 | — | 0.85 | MS3PROULTIMA-B-9 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-1-A | Constant +12V | power_in | MS3PROULTIMA-C-23 | Keep alive power | power_in | single_source | |
| OEM-1-B | ECU power +14V (main relay) | power_in | MS3PROULTIMA-A-35 | 12V+ switched power in | power_in | single_source | |
| OEM-1-C | Start signal | digital_in | MS3PROULTIMA-A-32 | Digital switched in 1 | digital_in | single_source | |
| OEM-1-E | Malfunction indicator lamp (MIL) | low_side_out | MS3PROULTIMA-A-14 | PWM / Idle Out 1 | low_side_out | single_source | |
| OEM-1-G | Ignition 1 (coils 1+4, wasted spark) | ignition_out | MS3PROULTIMA-B-13 | Spark out G | ignition_out | single_source | |
| OEM-1-H | Ignition 2 (coils 2+3, wasted spark) | ignition_out | MS3PROULTIMA-B-14 | Spark out E | ignition_out | single_source | |
| OEM-1-N | Wide-open throttle switch | digital_in | MS3PROULTIMA-B-20 | Digital switched in 2 | digital_in | single_source | |
| OEM-1-P | Power steering pressure switch | digital_in | MS3PROULTIMA-B-29 | Digital switched in 3 | digital_in | single_source | |
| OEM-1-Q | A/C request | digital_in | MS3PROULTIMA-C-11 | Digital switched in 4 | digital_in | single_source | |
| OEM-1-V | Neutral/clutch switch | digital_in | MS3PROULTIMA-C-10 | Digital switched in 5 | digital_in | single_source | |
| OEM-2-A | Power ground | ground | MS3PROULTIMA-A-13 + MS3PROULTIMA-B-18 + MS3PROULTIMA-B-3 + MS3PROULTIMA-B-5 + MS3PROULTIMA-B-7 + MS3PROULTIMA-B-9 | Power ground + Ground + Ground + Ground + Ground + Ground | ground | single_source | |
| OEM-2-B | Power ground | ground | MS3PROULTIMA-A-13 + MS3PROULTIMA-B-18 + MS3PROULTIMA-B-3 + MS3PROULTIMA-B-5 + MS3PROULTIMA-B-7 + MS3PROULTIMA-B-9 | Power ground + Ground + Ground + Ground + Ground + Ground | ground | single_source | |
| OEM-2-C | Power ground | ground | MS3PROULTIMA-A-13 + MS3PROULTIMA-B-18 + MS3PROULTIMA-B-3 + MS3PROULTIMA-B-5 + MS3PROULTIMA-B-7 + MS3PROULTIMA-B-9 | Power ground + Ground + Ground + Ground + Ground + Ground | ground | single_source | |
| OEM-2-D | Power ground | ground | MS3PROULTIMA-A-13 + MS3PROULTIMA-B-18 + MS3PROULTIMA-B-3 + MS3PROULTIMA-B-5 + MS3PROULTIMA-B-7 + MS3PROULTIMA-B-9 | Power ground + Ground + Ground + Ground + Ground + Ground | ground | single_source | |
| OEM-2-E | Crank position (CAS NE) | trigger_in | MS3PROULTIMA-A-6 | CKP+ | trigger_in | single_source | |
| OEM-2-F | AFM ground | sensor_ground | MS3PROULTIMA-A-15 + MS3PROULTIMA-A-16 + MS3PROULTIMA-A-18 + MS3PROULTIMA-A-27 + MS3PROULTIMA-C-17 + MS3PROULTIMA-C-18 + MS3PROULTIMA-C-19 + MS3PROULTIMA-C-20 + MS3PROULTIMA-C-21 | CKP− + Logic ground + Sensor return + CMP− + Sensor return + Sensor return + Sensor return + Sensor return + Sensor return | sensor_ground + trigger_in | single_source | |
| OEM-2-G | Cam position (CAS G) | trigger_in | MS3PROULTIMA-A-26 | CMP+ | trigger_in | single_source | |
| OEM-2-I | Tachometer output | tacho_out | MS3PROULTIMA-A-24 | Tach out | tacho_out | single_source | |
| OEM-2-K | +5V sensor supply | vref | MS3PROULTIMA-A-8 | 5V+ VREF out 1 | vref | single_source | |
| OEM-2-L | Idle switch (TPS) | digital_in | MS3PROULTIMA-B-28 | Digital frequency in 1 | digital_in | single_source | |
| OEM-2-N | O2 sensor | lambda_nb_in | MS3PROULTIMA-A-25 | O2 in | lambda_nb_in | single_source | |
| OEM-2-O | Air flow meter (AFM) | analog_in | MS3PROULTIMA-A-19 | Analog in 1 | analog_in | single_source | |
| OEM-2-P | Intake air temperature (IAT) | temp_in | MS3PROULTIMA-A-11 | CLT in | temp_in | single_source | |
| OEM-2-Q | Coolant temperature (ECT) | temp_in | MS3PROULTIMA-A-10 | MAT in | temp_in | single_source | |
| OEM-2-U | Injector 1 | injector_out | MS3PROULTIMA-A-3 | Injector out J | injector_out | single_source | |
| OEM-2-V | Injector 2 | injector_out | MS3PROULTIMA-A-4 | Injector out I | injector_out | single_source | |
| OEM-2-Y | Injector 3 | injector_out | MS3PROULTIMA-B-1 | Injector out A | injector_out | single_source | |
| OEM-2-Z | Injector 4 | injector_out | MS3PROULTIMA-B-10 | Injector out F | injector_out | single_source |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-1-B | SP-14V-1 | 0.85 | no route | ECU power +14V (main relay) | — | |
| W2 | SP-14V-1 | MS3PROULTIMA-A-35 | 0.85 | no route | 12V+ switched power in | — | |
| W3 | OEM-1-A | MS3PROULTIMA-C-23 | 0.85 | no route | Constant +12V | — | |
| W4 | OEM-2-A | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W5 | OEM-2-B | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W6 | OEM-2-C | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W7 | OEM-2-D | SP-GND-1 | 0.85 | no route | Power ground | — | |
| W8 | SP-GND-1 | MS3PROULTIMA-A-13 | 0.85 | no route | Power ground | — | |
| W9 | SP-GND-1 | MS3PROULTIMA-B-18 | 0.85 | no route | Ground | — | |
| W10 | SP-GND-1 | MS3PROULTIMA-B-3 | 0.85 | no route | Ground | — | |
| W11 | SP-GND-1 | MS3PROULTIMA-B-5 | 0.85 | no route | Ground | — | |
| W12 | SP-GND-1 | MS3PROULTIMA-B-7 | 0.85 | no route | Ground | — | |
| W13 | SP-GND-1 | MS3PROULTIMA-B-9 | 0.85 | no route | Ground | — | |
| W14 | OEM-2-F | SP-0V-1 | 0.5 | no route | AFM ground | — | |
| W15 | SP-0V-1 | MS3PROULTIMA-A-16 | 0.5 | no route | Logic ground | — | |
| W16 | SP-0V-1 | MS3PROULTIMA-A-18 | 0.5 | no route | Sensor return | — | |
| W17 | SP-0V-1 | MS3PROULTIMA-C-17 | 0.5 | no route | Sensor return | — | |
| W18 | SP-0V-1 | MS3PROULTIMA-C-18 | 0.5 | no route | Sensor return | — | |
| W19 | SP-0V-1 | MS3PROULTIMA-C-19 | 0.5 | no route | Sensor return | — | |
| W20 | SP-0V-1 | MS3PROULTIMA-C-20 | 0.5 | no route | Sensor return | — | |
| W21 | SP-0V-1 | MS3PROULTIMA-C-21 | 0.5 | no route | Sensor return | — | |
| W22 | OEM-2-K | MS3PROULTIMA-A-8 | 0.5 | no route | +5V sensor supply | — | |
| W23 | OEM-2-E | MS3PROULTIMA-A-6 | 0.5 | no route | Crank position (CAS NE) | — | |
| W24 | SP-0V-1 | MS3PROULTIMA-A-15 | 0.5 | no route | CKP− | — | |
| W25 | OEM-2-G | MS3PROULTIMA-A-26 | 0.5 | no route | Cam position (CAS G) | — | |
| W26 | SP-0V-1 | MS3PROULTIMA-A-27 | 0.5 | no route | CMP− | — | |
| W27 | OEM-1-G | MS3PROULTIMA-B-13 | 0.5 | no route | Ignition 1 (coils 1+4, wasted spark) | — | |
| W28 | OEM-1-H | MS3PROULTIMA-B-14 | 0.5 | no route | Ignition 2 (coils 2+3, wasted spark) | — | |
| W29 | OEM-2-U | MS3PROULTIMA-A-3 | 0.5 | no route | Injector 1 | — | |
| W30 | OEM-2-V | MS3PROULTIMA-A-4 | 0.5 | no route | Injector 2 | — | |
| W31 | OEM-2-Y | MS3PROULTIMA-B-1 | 0.5 | no route | Injector 3 | — | |
| W32 | OEM-2-Z | MS3PROULTIMA-B-10 | 0.5 | no route | Injector 4 | — | |
| W33 | OEM-1-E | MS3PROULTIMA-A-14 | 0.5 | no route | Malfunction indicator lamp (MIL) | — | |
| W34 | OEM-2-I | MS3PROULTIMA-A-24 | 0.5 | no route | Tachometer output | — | |
| W35 | OEM-2-O | MS3PROULTIMA-A-19 | 0.5 | no route | Air flow meter (AFM) | — | |
| W36 | OEM-2-N | MS3PROULTIMA-A-25 | 0.5 | no route | O2 sensor | — | |
| W37 | OEM-2-Q | MS3PROULTIMA-A-10 | 0.5 | no route | Coolant temperature (ECT) | — | |
| W38 | OEM-2-P | MS3PROULTIMA-A-11 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W39 | OEM-1-C | MS3PROULTIMA-A-32 | 0.5 | no route | Start signal | — | |
| W40 | OEM-1-N | MS3PROULTIMA-B-20 | 0.5 | no route | Wide-open throttle switch | — | |
| W41 | OEM-1-P | MS3PROULTIMA-B-29 | 0.5 | no route | Power steering pressure switch | — | |
| W42 | OEM-1-Q | MS3PROULTIMA-C-11 | 0.5 | no route | A/C request | — | |
| W43 | OEM-1-V | MS3PROULTIMA-C-10 | 0.5 | no route | Neutral/clutch switch | — | |
| W44 | OEM-2-L | MS3PROULTIMA-B-28 | 0.5 | no route | Idle switch (TPS) | — |
Bill of materials
| Category | Part number | Manufacturer | Description | Qty | Unit |
|---|---|---|---|---|---|
| connector | 174515-6 | TE | AMP Multilock .040/.070 hybrid 22-pin female harness plug (Miata NA/NB ECU) | 1.000 | ea |
| connector | 174516-6 | TE | AMP Multilock .040/.070 hybrid 26-pin female harness plug (Miata NA/NB ECU) | 1.000 | ea |
ECU setup sheet
| Role | Engine ref | Engine signal | Sensor | ECU point | ECU function | ECU class | Setup flag |
|---|---|---|---|---|---|---|---|
| No configured channels. | |||||||
Findings
Open (1)
| Severity | Code | Subject | Message |
|---|---|---|---|
| info | NET_FAMILY | MS3PROULTIMA-A-27 ↔ MS3PROULTIMA-C-19 | MS3PROULTIMA-A-27 "CMP−" [trigger_in] is wired to MS3PROULTIMA-C-19 "Sensor return" [sensor_ground]. Trigger return tied to sensor/trigger ground: correct for single-ended trigger inputs. |
Accepted (0)
| Code | Subject | Reason | By |
|---|
Notes
Auto-mapped by auto_map() from the library pin data on 2026-10-06. Review every wire against both manuals before building. Not wired: - MS3PROULTIMA-B 19: Digital switched 12V in: 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 | AMP EFI: MS3Pro Ultimate manual (v1.210, fw 1.5.2) pinout tables | https://cdn.shopify.com/s/files/1/0960/0014/7754/files/MS3Pro_User_Manual_Firmware_1.5.2_ULTIMATE.pdf?v=1760706068 | archive | 2026-10-05 | 71ed7ed81581 |
| 4 | vendor_doc | Link G4X MX5X install manual (NA 1.6/1.8) | https://linkecu.com/documentation/MX5X.pdf | archive | 2026-10-05 | b7f730de9f6e |