MX-5 Miata NA6 1990-93 (B6-ZE, 1.6) → Motorsport Electronics ME442 (auto)
MX-5 Miata NA6 1990-93 (B6-ZE, 1.6) — Motorsport Electronics — ME442
Drawn by Michael Gnankou · Rev 0 · proposal · 2026-10-09
Before you start
| Status | proposal · not yet verified: nobody has reported building and running this harness |
|---|---|
| Open errors | none |
| Size of the job | 35 wires · 6 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 | ME442-C1-14 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | SP-14V-1 | ME442-C1-64 | 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 | ME442-C1-10 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | SP-GND-1 | ME442-C1-61 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | SP-GND-1 | ME442-C1-89 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | SP-GND-1 | ME442-C1-90 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-2-F | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | SP-0V-1 | ME442-C1-52 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | SP-0V-1 | ME442-C1-84 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W15 | OEM-2-K | ME442-C1-45 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W16 | OEM-2-E | ME442-C1-80 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W17 | OEM-2-G | ME442-C1-22 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W18 | OEM-1-G | ME442-C1-32 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W19 | OEM-1-H | ME442-C1-31 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W20 | OEM-2-U | ME442-C1-63 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W21 | OEM-2-V | ME442-C1-4 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W22 | OEM-2-Y | ME442-C1-33 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W23 | OEM-2-Z | ME442-C1-3 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W24 | OEM-1-E | ME442-C1-73 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W25 | OEM-2-I | ME442-C1-79 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W26 | OEM-2-O | ME442-C1-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W27 | OEM-2-N | ME442-C1-56 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W28 | OEM-2-Q | ME442-C1-86 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W29 | OEM-2-P | ME442-C1-57 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W30 | OEM-1-C | ME442-C1-6 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W31 | OEM-1-N | ME442-C1-7 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W32 | OEM-1-P | ME442-C1-8 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W33 | OEM-1-Q | ME442-C1-5 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W34 | OEM-1-V | ME442-C1-62 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W35 | OEM-2-L | ME442-C1-34 | 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 | ME442-C1-14 | ME442-C1-10 | open (OL) | +12 V supply must not touch power ground | |
| 2 | ME442-C1-14 | ME442-C1-52 | open (OL) | +12 V supply must not touch sensor ground | |
| 3 | ME442-C1-10 | ME442-C1-45 | open (OL) | power ground must not touch 5 V sensor reference | |
| 4 | ME442-C1-14 | ME442-C1-45 | open (OL) | +12 V supply must not touch 5 V sensor reference | |
| 5 | ME442-C1-52 | ME442-C1-45 | open (OL) | sensor ground must not touch 5 V sensor reference |
Revisions
| Rev | Label | By | Date |
|---|---|---|---|
| No revisions yet. | |||
Schematic
Connectors
ME442-C1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | COIL 4 | — | — | — | — | — | — | — | — |
| 10 | GROUND CHASSIS | — | W8 | — | 0.85 | SP-GND-1 | — | — | — |
| 11 | EGT 1 | — | — | — | — | — | — | — | — |
| 12 | LOW SIDE 2 | — | — | — | — | — | — | — | — |
| 13 | LOW SIDE RELAY 15 | — | — | — | — | — | — | — | — |
| 14 | VBAT IGNITION | — | W2 | — | 0.85 | SP-14V-1 | — | — | — |
| 15 | LSU HEATER +VE | — | — | — | — | — | — | — | — |
| 16 | LSU HEATER -VE | — | — | — | — | — | — | — | — |
| 17 | ANA VOLT 3 | — | — | — | — | — | — | — | — |
| 18 | ANA VOLT 4 | — | — | — | — | — | — | — | — |
| 19 | LSU UN | — | — | — | — | — | — | — | — |
| 2 | COIL 3 | — | — | — | — | — | — | — | — |
| 20 | LSU VM | — | — | — | — | — | — | — | — |
| 21 | CAN 1 HIGH | — | — | — | — | — | — | — | — |
| 22 | CAM A VR+ | — | W17 | — | 0.5 | OEM-2-G | — | — | — |
| 23 | CAM A VR- | — | — | — | — | — | — | — | — |
| 24 | SERIAL 1 GROUND | — | — | — | — | — | — | — | — |
| 25 | SERIAL 1 TX | — | — | — | — | — | — | — | — |
| 26 | ANA VOLT 1 | — | W26 | — | 0.5 | OEM-2-O | — | — | — |
| 27 | INJECTOR 8 | — | — | — | — | — | — | — | — |
| 28 | INJECTOR 5 | — | — | — | — | — | — | — | — |
| 29 | COIL 7 | — | — | — | — | — | — | — | — |
| 3 | INJECTOR 4 | — | W23 | — | 0.5 | OEM-2-Z | — | — | — |
| 30 | COIL 8 | — | — | — | — | — | — | — | — |
| 31 | COIL 2 | — | W19 | — | 0.5 | OEM-1-H | — | — | — |
| 32 | COIL 1 | — | W18 | — | 0.5 | OEM-1-G | — | — | — |
| 33 | INJECTOR 3 | — | W22 | — | 0.5 | OEM-2-Y | — | — | — |
| 34 | DIG_IN 6 | — | W35 | — | 0.5 | OEM-2-L | — | — | — |
| 35 | USB D+ | — | — | — | — | — | — | — | — |
| 36 | USB D- | — | — | — | — | — | — | — | — |
| 37 | LOW SIDE RELAY 11 | — | — | — | — | — | — | — | — |
| 38 | USB VBUS | — | — | — | — | — | — | — | — |
| 39 | LOW SIDE 6 | — | — | — | — | — | — | — | — |
| 4 | INJECTOR 2 | — | W21 | — | 0.5 | OEM-2-V | — | — | — |
| 40 | LOW SIDE RELAY 17 | — | — | — | — | — | — | — | — |
| 41 | USB GROUND | — | — | — | — | — | — | — | — |
| 42 | LOW SIDE RELAY 12 | — | — | — | — | — | — | — | — |
| 43 | LOW SIDE RELAY 14 | — | — | — | — | — | — | — | — |
| 44 | LOW SIDE 4 | — | — | — | — | — | — | — | — |
| 45 | 5V REF | — | W15 | — | 0.5 | OEM-2-K | — | — | — |
| 46 | 5V REF | — | — | — | — | — | — | — | — |
| 47 | ANA TEMP 4 | — | — | — | — | — | — | — | — |
| 48 | ANA VOLT 7 | — | — | — | — | — | — | — | — |
| 49 | LSU IA | — | — | — | — | — | — | — | — |
| 5 | DIG_IN 4 | — | W33 | — | 0.5 | OEM-1-Q | — | — | — |
| 50 | LSU IP | — | — | — | — | — | — | — | — |
| 51 | CAN 1 LOW | — | — | — | — | — | — | — | — |
| 52 | SENSORS GROUND | — | W13 | — | 0.5 | SP-0V-1 | — | — | — |
| 53 | KNOCK 1 SIGNAL | — | — | — | — | — | — | — | — |
| 54 | KNOCK 2 SIGNAL | — | — | — | — | — | — | — | — |
| 55 | SERIAL 1 RX | — | — | — | — | — | — | — | — |
| 56 | ANA VOLT 2 | — | W27 | — | 0.5 | OEM-2-N | — | — | — |
| 57 | ANA TEMP 2 | — | W29 | — | 0.5 | OEM-2-P | — | — | — |
| 58 | INJECTOR 6 | — | — | — | — | — | — | — | — |
| 59 | COIL 5 | — | — | — | — | — | — | — | — |
| 6 | DIG_IN 1 | — | W30 | — | 0.5 | OEM-1-C | — | — | — |
| 60 | COIL 6 | — | — | — | — | — | — | — | — |
| 61 | GROUND | — | W9 | — | 0.85 | SP-GND-1 | — | — | — |
| 62 | DIG_IN 5 | — | W34 | — | 0.5 | OEM-1-V | — | — | — |
| 63 | INJECTOR 1 | — | W20 | — | 0.5 | OEM-2-U | — | — | — |
| 64 | VBAT | — | W3 | — | 0.85 | SP-14V-1 | — | — | — |
| 65 | H-BRIDGE A OUT 1 | — | — | — | — | — | — | — | — |
| 66 | H-BRIDGE A OUT 2 | — | — | — | — | — | — | — | — |
| 67 | Stepper 1 / A1 | — | — | — | — | — | — | — | — |
| 68 | Stepper 2 / A2 | — | — | — | — | — | — | — | — |
| 69 | LOW SIDE 5 | — | — | — | — | — | — | — | — |
| 7 | DIG_IN 2 | — | W31 | — | 0.5 | OEM-1-N | — | — | — |
| 70 | Stepper 3 / B1 | — | — | — | — | — | — | — | — |
| 71 | Stepper 4 / B2 | — | — | — | — | — | — | — | — |
| 72 | LOW SIDE RELAY 13 | — | — | — | — | — | — | — | — |
| 73 | LOW SIDE 1 | — | W24 | — | 0.5 | OEM-1-E | — | — | — |
| 74 | LOW SIDE 3 | — | — | — | — | — | — | — | — |
| 75 | LOW SIDE RELAY 16 | — | — | — | — | — | — | — | — |
| 76 | 5V REF | — | — | — | — | — | — | — | — |
| 77 | ANA TEMP 3 | — | — | — | — | — | — | — | — |
| 78 | ANA VOLT 6 | — | — | — | — | — | — | — | — |
| 79 | TACHOMETER | — | W25 | — | 0.5 | OEM-2-I | — | — | — |
| 8 | DIG_IN 3 | — | W32 | — | 0.5 | OEM-1-P | — | — | — |
| 80 | CRANK VR+ | — | W16 | — | 0.5 | OEM-2-E | — | — | — |
| 81 | CRANK VR- | — | — | — | — | — | — | — | — |
| 82 | CAM B VR+ | — | — | — | — | — | — | — | — |
| 83 | CAM B VR- | — | — | — | — | — | — | — | — |
| 84 | Sensor Ground | — | W14 | — | 0.5 | SP-0V-1 | — | — | — |
| 86 | ANA TEMP 1 | — | W28 | — | 0.5 | OEM-2-Q | — | — | — |
| 87 | ANA VOLT 5 | — | — | — | — | — | — | — | — |
| 88 | INJECTOR 7 | — | — | — | — | — | — | — | — |
| 89 | GROUND | — | W10 | — | 0.85 | SP-GND-1 | — | — | — |
| 9 | LOW SIDE RELAY 18 | — | — | — | — | — | — | — | — |
| 90 | GROUND | — | W11 | — | 0.85 | SP-GND-1 | — | — | — |
OEM-1
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| A | Constant +12V | — | — | — | — | — | — | — | — |
| B | ECU power +14V (main relay) | — | W1 | — | 0.85 | SP-14V-1 | — | — | — |
| C | Start signal | — | W30 | — | 0.5 | ME442-C1-6 | — | — | — |
| E | Malfunction indicator lamp (MIL) | — | W24 | — | 0.5 | ME442-C1-73 | — | — | — |
| G | Ignition 1 (coils 1+4, wasted spark) | — | W18 | — | 0.5 | ME442-C1-32 | — | — | — |
| H | Ignition 2 (coils 2+3, wasted spark) | — | W19 | — | 0.5 | ME442-C1-31 | — | — | — |
| N | Wide-open throttle switch | — | W31 | — | 0.5 | ME442-C1-7 | — | — | — |
| P | Power steering pressure switch | — | W32 | — | 0.5 | ME442-C1-8 | — | — | — |
| Q | A/C request | — | W33 | — | 0.5 | ME442-C1-5 | — | — | — |
| V | Neutral/clutch switch | — | W34 | — | 0.5 | ME442-C1-62 | — | — | — |
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) | — | W16 | — | 0.5 | ME442-C1-80 | — | — | — |
| F | AFM ground | — | W12 | — | 0.5 | SP-0V-1 | — | — | — |
| G | Cam position (CAS G) | — | W17 | — | 0.5 | ME442-C1-22 | — | — | — |
| I | Tachometer output | — | W25 | — | 0.5 | ME442-C1-79 | — | — | — |
| K | +5V sensor supply | — | W15 | — | 0.5 | ME442-C1-45 | — | — | — |
| L | Idle switch (TPS) | — | W35 | — | 0.5 | ME442-C1-34 | — | — | — |
| N | O2 sensor | — | W27 | — | 0.5 | ME442-C1-56 | — | — | — |
| O | Air flow meter (AFM) | — | W26 | — | 0.5 | ME442-C1-26 | — | — | — |
| P | Intake air temperature (IAT) | — | W29 | — | 0.5 | ME442-C1-57 | — | — | — |
| Q | Coolant temperature (ECT) | — | W28 | — | 0.5 | ME442-C1-86 | — | — | — |
| U | Injector 1 | — | W20 | — | 0.5 | ME442-C1-63 | — | — | — |
| V | Injector 2 | — | W21 | — | 0.5 | ME442-C1-4 | — | — | — |
| Y | Injector 3 | — | W22 | — | 0.5 | ME442-C1-33 | — | — | — |
| Z | Injector 4 | — | W23 | — | 0.5 | ME442-C1-3 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W12 | — | 0.5 | OEM-2-F | — | — | — |
| 1 | — | — | W13 | — | 0.5 | ME442-C1-52 | — | — | — |
| 1 | — | — | W14 | — | 0.5 | ME442-C1-84 | — | — | — |
SP-14V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-1-B | — | — | — |
| 1 | — | — | W2 | — | 0.85 | ME442-C1-14 | — | — | — |
| 1 | — | — | W3 | — | 0.85 | ME442-C1-64 | — | — | — |
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 | ME442-C1-10 | — | — | — |
| 1 | — | — | W9 | — | 0.85 | ME442-C1-61 | — | — | — |
| 1 | — | — | W10 | — | 0.85 | ME442-C1-89 | — | — | — |
| 1 | — | — | W11 | — | 0.85 | ME442-C1-90 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-1-A | Constant +12V | power_in | — | — | — | single_source | |
| OEM-1-B | ECU power +14V (main relay) | power_in | ME442-C1-14 + ME442-C1-64 | VBAT IGNITION + VBAT | power_in | single_source | |
| OEM-1-C | Start signal | digital_in | ME442-C1-6 | DIG_IN 1 | digital_in | single_source | |
| OEM-1-E | Malfunction indicator lamp (MIL) | low_side_out | ME442-C1-73 | LOW SIDE 1 | low_side_out | single_source | |
| OEM-1-G | Ignition 1 (coils 1+4, wasted spark) | ignition_out | ME442-C1-32 | COIL 1 | ignition_out | single_source | |
| OEM-1-H | Ignition 2 (coils 2+3, wasted spark) | ignition_out | ME442-C1-31 | COIL 2 | ignition_out | single_source | |
| OEM-1-N | Wide-open throttle switch | digital_in | ME442-C1-7 | DIG_IN 2 | digital_in | single_source | |
| OEM-1-P | Power steering pressure switch | digital_in | ME442-C1-8 | DIG_IN 3 | digital_in | single_source | |
| OEM-1-Q | A/C request | digital_in | ME442-C1-5 | DIG_IN 4 | digital_in | single_source | |
| OEM-1-V | Neutral/clutch switch | digital_in | ME442-C1-62 | DIG_IN 5 | digital_in | single_source | |
| OEM-2-A | Power ground | ground | ME442-C1-10 + ME442-C1-61 + ME442-C1-89 + ME442-C1-90 | GROUND CHASSIS + GROUND + GROUND + GROUND | ground | single_source | |
| OEM-2-B | Power ground | ground | ME442-C1-10 + ME442-C1-61 + ME442-C1-89 + ME442-C1-90 | GROUND CHASSIS + GROUND + GROUND + GROUND | ground | single_source | |
| OEM-2-C | Power ground | ground | ME442-C1-10 + ME442-C1-61 + ME442-C1-89 + ME442-C1-90 | GROUND CHASSIS + GROUND + GROUND + GROUND | ground | single_source | |
| OEM-2-D | Power ground | ground | ME442-C1-10 + ME442-C1-61 + ME442-C1-89 + ME442-C1-90 | GROUND CHASSIS + GROUND + GROUND + GROUND | ground | single_source | |
| OEM-2-E | Crank position (CAS NE) | trigger_in | ME442-C1-80 | CRANK VR+ | trigger_in | single_source | |
| OEM-2-F | AFM ground | sensor_ground | ME442-C1-52 + ME442-C1-84 | SENSORS GROUND + Sensor Ground | sensor_ground | single_source | |
| OEM-2-G | Cam position (CAS G) | trigger_in | ME442-C1-22 | CAM A VR+ | trigger_in | single_source | |
| OEM-2-I | Tachometer output | tacho_out | ME442-C1-79 | TACHOMETER | tacho_out | single_source | |
| OEM-2-K | +5V sensor supply | vref | ME442-C1-45 | 5V REF | vref | single_source | |
| OEM-2-L | Idle switch (TPS) | digital_in | ME442-C1-34 | DIG_IN 6 | digital_in | single_source | |
| OEM-2-N | O2 sensor | lambda_nb_in | ME442-C1-56 | ANA VOLT 2 | analog_in | single_source | |
| OEM-2-O | Air flow meter (AFM) | analog_in | ME442-C1-26 | ANA VOLT 1 | analog_in | single_source | |
| OEM-2-P | Intake air temperature (IAT) | temp_in | ME442-C1-57 | ANA TEMP 2 | temp_in | single_source | |
| OEM-2-Q | Coolant temperature (ECT) | temp_in | ME442-C1-86 | ANA TEMP 1 | temp_in | single_source | |
| OEM-2-U | Injector 1 | injector_out | ME442-C1-63 | INJECTOR 1 | injector_out | single_source | |
| OEM-2-V | Injector 2 | injector_out | ME442-C1-4 | INJECTOR 2 | injector_out | single_source | |
| OEM-2-Y | Injector 3 | injector_out | ME442-C1-33 | INJECTOR 3 | injector_out | single_source | |
| OEM-2-Z | Injector 4 | injector_out | ME442-C1-3 | INJECTOR 4 | 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 | ME442-C1-14 | 0.85 | no route | VBAT IGNITION | — | |
| W3 | SP-14V-1 | ME442-C1-64 | 0.85 | no route | VBAT | — | |
| 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 | ME442-C1-10 | 0.85 | no route | GROUND CHASSIS | — | |
| W9 | SP-GND-1 | ME442-C1-61 | 0.85 | no route | GROUND | — | |
| W10 | SP-GND-1 | ME442-C1-89 | 0.85 | no route | GROUND | — | |
| W11 | SP-GND-1 | ME442-C1-90 | 0.85 | no route | GROUND | — | |
| W12 | OEM-2-F | SP-0V-1 | 0.5 | no route | AFM ground | — | |
| W13 | SP-0V-1 | ME442-C1-52 | 0.5 | no route | SENSORS GROUND | — | |
| W14 | SP-0V-1 | ME442-C1-84 | 0.5 | no route | Sensor Ground | — | |
| W15 | OEM-2-K | ME442-C1-45 | 0.5 | no route | +5V sensor supply | — | |
| W16 | OEM-2-E | ME442-C1-80 | 0.5 | no route | Crank position (CAS NE) | — | |
| W17 | OEM-2-G | ME442-C1-22 | 0.5 | no route | Cam position (CAS G) | — | |
| W18 | OEM-1-G | ME442-C1-32 | 0.5 | no route | Ignition 1 (coils 1+4, wasted spark) | — | |
| W19 | OEM-1-H | ME442-C1-31 | 0.5 | no route | Ignition 2 (coils 2+3, wasted spark) | — | |
| W20 | OEM-2-U | ME442-C1-63 | 0.5 | no route | Injector 1 | — | |
| W21 | OEM-2-V | ME442-C1-4 | 0.5 | no route | Injector 2 | — | |
| W22 | OEM-2-Y | ME442-C1-33 | 0.5 | no route | Injector 3 | — | |
| W23 | OEM-2-Z | ME442-C1-3 | 0.5 | no route | Injector 4 | — | |
| W24 | OEM-1-E | ME442-C1-73 | 0.5 | no route | Malfunction indicator lamp (MIL) | — | |
| W25 | OEM-2-I | ME442-C1-79 | 0.5 | no route | Tachometer output | — | |
| W26 | OEM-2-O | ME442-C1-26 | 0.5 | no route | Air flow meter (AFM) | — | |
| W27 | OEM-2-N | ME442-C1-56 | 0.5 | no route | O2 sensor | — | |
| W28 | OEM-2-Q | ME442-C1-86 | 0.5 | no route | Coolant temperature (ECT) | — | |
| W29 | OEM-2-P | ME442-C1-57 | 0.5 | no route | Intake air temperature (IAT) | — | |
| W30 | OEM-1-C | ME442-C1-6 | 0.5 | no route | Start signal | — | |
| W31 | OEM-1-N | ME442-C1-7 | 0.5 | no route | Wide-open throttle switch | — | |
| W32 | OEM-1-P | ME442-C1-8 | 0.5 | no route | Power steering pressure switch | — | |
| W33 | OEM-1-Q | ME442-C1-5 | 0.5 | no route | A/C request | — | |
| W34 | OEM-1-V | ME442-C1-62 | 0.5 | no route | Neutral/clutch switch | — | |
| W35 | OEM-2-L | ME442-C1-34 | 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 (0)
| Severity | Code | Subject | Message |
|---|
Accepted (1)
| Code | Subject | Reason | By |
|---|---|---|---|
| REQUIRED_UNMAPPED | OEM-1-A | 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 2026-10-08. Review every wire against both manuals before building. Not wired: - OEM-1 A: Constant +12V: Motorsport Electronics ME442 has no battery-constant input; not needed
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | Link G4X MX5X install manual (NA 1.6/1.8) | https://linkecu.com/documentation/MX5X.pdf | archive | 2026-10-05 | b7f730de9f6e |
| 4 | vendor_doc | Motorsport Electronics GEN2 ME221/ME360/ME442 wire-in pinout | https://motorsport-electronics.co.uk/onlinehelp/html/ME442ME360ME221GEN2Wire-InPinout.html | — | — | — |