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Toyota Supra A70 1986-92 (7M-GTE) → Speeduino Speeduino v0.4 (auto)

Toyota Supra A70 1986-92 (7M-GTE) — 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.

Statusdraft · not yet verified: nobody has reported building and running this harness
Open errors1: read the Findings page before cutting any wire
Size of the job20 wires · 11 connectors · 0 part lines
ToolsCrimp and extraction tools for each terminal family (see Connectors) · wire strippers · multimeter · heat gun + heat-shrink
Order of work1. 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.

WireFromToGaugeColourCutLabelCrimp ACrimp BPin APin BContinuity
W1NEW-KEYON-1MAIN-R-COIL+0.5☐☐☐☐☐☐☐
W2NEW-BATT-1MAIN-R-IN0.85☐☐☐☐☐☐☐
W3MAIN-R-COIL-SP-GND-10.5☐☐☐☐☐☐☐
W4MAIN-R-OUTSPEEDUINO-PWR-12V0.85☐☐☐☐☐☐☐
W5OEM-A-26SP-GND-10.85☐☐☐☐☐☐☐
W6SP-GND-1SPEEDUINO-A-100.85☐☐☐☐☐☐☐
W7SP-GND-1SPEEDUINO-A-90.85☐☐☐☐☐☐☐
W8OEM-B-9SP-0V-10.5☐☐☐☐☐☐☐
W9SP-0V-1SPEEDUINO-A-120.5☐☐☐☐☐☐☐
W10SP-0V-1SPEEDUINO-A-230.5☐☐☐☐☐☐☐
W11OEM-A-12SPEEDUINO-A-10.5☐☐☐☐☐☐☐
W12OEM-A-11SPEEDUINO-A-20.5☐☐☐☐☐☐☐
W13OEM-A-25SPEEDUINO-A-30.5☐☐☐☐☐☐☐
W14SPEEDUINO-A-16NEW-FUELPUMP-10.5☐☐☐☐☐☐☐
W15OEM-B-11SPEEDUINO-A-220.5☐☐☐☐☐☐☐
W16OEM-B-4SPEEDUINO-A-190.5☐☐☐☐☐☐☐
W17OEM-B-2SPEEDUINO-A-140.5☐☐☐☐☐☐☐
W18OEM-B-6SPEEDUINO-A-210.5☐☐☐☐☐☐☐
W19OEM-B-3SPEEDUINO-A-200.5☐☐☐☐☐☐☐
W20OEM-D-9SPEEDUINO-A-180.5☐☐☐☐☐☐☐

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 AProbe BExpectWhyReading
1MAIN-R-COIL-MAIN-R-OUTopen (OL)power ground must not touch +12 V supply
2MAIN-R-COIL-NEW-BATT-1open (OL)power ground must not touch +12 V supply
3MAIN-R-COIL-NEW-KEYON-1open (OL)power ground must not touch +12 V supply
4SPEEDUINO-A-12MAIN-R-OUTopen (OL)sensor ground must not touch +12 V supply
5SPEEDUINO-A-12NEW-BATT-1open (OL)sensor ground must not touch +12 V supply
6SPEEDUINO-A-12NEW-KEYON-1open (OL)sensor ground must not touch +12 V supply

If any reading doesn't match, stop and get help before powering up.

Revisions

RevLabelByDate
No revisions yet.

Schematic

MAIN-RNEW-BATTNEW-FUELPUMPNEW-KEYONOEM-AOEM-BOEM-DSP-0VSP-GNDSPEEDUINO-ASPEEDUINO-PWR

Connectors

MAIN-R

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
COIL+Relay coil positive (ignition-switched +12V)—W1—0.5NEW-KEYON-1———
COIL-Relay coil negative (ECU low-side driver)—W3—0.5SP-GND-1———
INRelay contact input (battery + via main fuse)—W2—0.85NEW-BATT-1———
OUTRelay contact output (switched +12V bus)—W4—0.85SPEEDUINO-PWR-12V———

NEW-BATT

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W2—0.85MAIN-R-IN———

NEW-FUELPUMP

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W14—0.5SPEEDUINO-A-16———

NEW-KEYON

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W1—0.5MAIN-R-COIL+———

OEM-A

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
11Injectors 2 & 6 (No.20)—W12—0.5SPEEDUINO-A-2———
12Injectors 1 & 4 (No.10)—W11—0.5SPEEDUINO-A-1———
25Injectors 3 & 5 (No.30)—W13—0.5SPEEDUINO-A-3———
26Power ground (E01/E02)—W5—0.85SP-GND-1———

OEM-B

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
11Throttle position sensor (VTA)—W15—0.5SPEEDUINO-A-22———
2Karman-vortex AFM signal (KS)—W17—0.5SPEEDUINO-A-14———
3Intake air temp (THA)—W19—0.5SPEEDUINO-A-20———
4Coolant temp (THW)—W16—0.5SPEEDUINO-A-19———
6Primary O2 sensor (OX1)—W18—0.5SPEEDUINO-A-21———
9Sensor ground (E2)—W8—0.5SP-0V-1———

OEM-D

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
9Vehicle speed sensor (SPD)—W20—0.5SPEEDUINO-A-18———

SP-0V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W8—0.5OEM-B-9———
1——W9—0.5SPEEDUINO-A-12———
1——W10—0.5SPEEDUINO-A-23———

SP-GND

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W3—0.5MAIN-R-COIL-———
1——W5—0.85OEM-A-26———
1——W6—0.85SPEEDUINO-A-10———
1——W7—0.85SPEEDUINO-A-9———

SPEEDUINO-A

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Injector 1—W11—0.5OEM-A-12———
10Ground—W6—0.85SP-GND-1———
11MAP sensor (0-5V)————————
12Ground—W9—0.5SP-0V-1———
135V————————
14Proto area 1 (flex fuel)—W17—0.5OEM-B-2———
15Proto area 2 (fan)————————
16Proto area 3 (fuel pump)—W14—0.5NEW-FUELPUMP-1———
17Proto area 4 (tachometer)————————
18Proto area 5 (clutch)—W20—0.5OEM-D-9———
19Coolant temp (CLT)—W16—0.5OEM-B-4———
2Injector 2—W12—0.5OEM-A-11———
20Inlet air temp (IAT)—W19—0.5OEM-B-3———
21O2 sensor—W18—0.5OEM-B-6———
22TPS input—W15—0.5OEM-B-11———
23Ground—W10—0.5SP-0V-1———
24Cam input / VR2+————————
25Crank input / VR1+————————
26VR2-————————
27VR1-————————
285V————————
29Idle stepper 2B————————
3Injector 3—W13—0.5OEM-A-25———
30Idle stepper 2A————————
31Idle stepper 1A————————
32Idle stepper 1B————————
33Ignition 3————————
34Ignition 2————————
35Boost————————
36Idle 2 (3-wire idle)————————
37PWM idle————————
38VVT————————
5Injector 4————————
7Ignition 1————————
8Ignition 4————————
9Ground—W7—0.85SP-GND-1———

SPEEDUINO-PWR

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
12VMain power (+12 V switched)—W4—0.85MAIN-R-OUT———

Pin map

OEM pointOEM functionOEM familyTarget pointTarget functionTarget familyWire colourEvidence
OEM-A-11Injectors 2 & 6 (No.20)injector_outSPEEDUINO-A-2Injector 2injector_outcorroborated
OEM-A-12Injectors 1 & 4 (No.10)injector_outSPEEDUINO-A-1Injector 1injector_outcorroborated
OEM-A-25Injectors 3 & 5 (No.30)injector_outSPEEDUINO-A-3Injector 3injector_outcorroborated
OEM-A-26Power ground (E01/E02)groundMAIN-R-COIL- + SPEEDUINO-A-10 + SPEEDUINO-A-9Relay coil negative (ECU low-side driver) + Ground + Groundground + loadcorroborated
OEM-B-11Throttle position sensor (VTA)analog_inSPEEDUINO-A-22TPS inputanalog_incorroborated
OEM-B-2Karman-vortex AFM signal (KS)digital_inSPEEDUINO-A-14Proto area 1 (flex fuel)digital_incorroborated
OEM-B-3Intake air temp (THA)temp_inSPEEDUINO-A-20Inlet air temp (IAT)temp_incorroborated
OEM-B-4Coolant temp (THW)temp_inSPEEDUINO-A-19Coolant temp (CLT)temp_incorroborated
OEM-B-6Primary O2 sensor (OX1)lambda_nb_inSPEEDUINO-A-21O2 sensorlambda_nb_incorroborated
OEM-B-9Sensor ground (E2)sensor_groundSPEEDUINO-A-12 + SPEEDUINO-A-23Ground + Groundsensor_groundcorroborated
OEM-D-9Vehicle speed sensor (SPD)digital_inSPEEDUINO-A-18Proto area 5 (clutch)digital_incorroborated

Cut list

WireFromToGauge (mm²)ColourLengthSignalIdent
W1NEW-KEYON-1MAIN-R-COIL+0.5no routeRelay coil positive (ignition-switched +12V)—
W2NEW-BATT-1MAIN-R-IN0.85no routeRelay contact input (battery + via main fuse)—
W3MAIN-R-COIL-SP-GND-10.5no routeRelay coil negative (ECU low-side driver)—
W4MAIN-R-OUTSPEEDUINO-PWR-12V0.85no routeRelay contact output (switched +12V bus)—
W5OEM-A-26SP-GND-10.85no routePower ground (E01/E02)—
W6SP-GND-1SPEEDUINO-A-100.85no routeGround—
W7SP-GND-1SPEEDUINO-A-90.85no routeGround—
W8OEM-B-9SP-0V-10.5no routeSensor ground (E2)—
W9SP-0V-1SPEEDUINO-A-120.5no routeGround—
W10SP-0V-1SPEEDUINO-A-230.5no routeGround—
W11OEM-A-12SPEEDUINO-A-10.5no routeInjectors 1 & 4 (No.10)—
W12OEM-A-11SPEEDUINO-A-20.5no routeInjectors 2 & 6 (No.20)—
W13OEM-A-25SPEEDUINO-A-30.5no routeInjectors 3 & 5 (No.30)—
W14SPEEDUINO-A-16NEW-FUELPUMP-10.5no routeProto area 3 (fuel pump)—
W15OEM-B-11SPEEDUINO-A-220.5no routeThrottle position sensor (VTA)—
W16OEM-B-4SPEEDUINO-A-190.5no routeCoolant temp (THW)—
W17OEM-B-2SPEEDUINO-A-140.5no routeKarman-vortex AFM signal (KS)—
W18OEM-B-6SPEEDUINO-A-210.5no routePrimary O2 sensor (OX1)—
W19OEM-B-3SPEEDUINO-A-200.5no routeIntake air temp (THA)—
W20OEM-D-9SPEEDUINO-A-180.5no routeVehicle speed sensor (SPD)—

Bill of materials

CategoryPart numberManufacturerDescriptionQtyUnit

ECU setup sheet

RoleEngine refEngine signalSensorECU pointECU functionECU classSetup flag
No configured channels.

Findings

Open (1)

SeverityCodeSubjectMessage
errorINJECTOR_BALLASTSpeeduinoThe 7M-GTE injectors (7M-GTE 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.

Accepted (0)

CodeSubjectReasonBy

Notes

Fit check: needs add-on. Resolve these before building: - Low-impedance injectors need a ballast resistor pack in series with each injector, or an ECU with low-Z / peak-and-hold injector drivers - Trigger pattern for Toyota 7M-GTE not found in the ECU's docs (Confirmed absent from documented trigger/decoder list. No 7M-GTE (24+2 Nippondenso CAS) decoder exists. The 'Toyota 3 tooth cam' decoder covers 1UZ/1JZ/2JZ-VVT-i/1FZ-FE, not the 7M.) - 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 2026-10-20. Review every wire against both manuals before building. Open items: - Main-relay feed: no switched power (ecu_main_power / switched_feed) on the stock ECU

Sources

ReliabilityKindTitleURLArchiveCapturedSHA-256
4vendor_docEmtron SL4/SL6/SL8 pinout pageshttps://docs.emtronaustralia.com.au/engine-management/wiring/index.htmlarchive2026-10-05e52b3da9996a
4vendor_docSpeeduino Manual (08/04/25) — V0.4 board IDC40 pinout & featureshttps://speeduino.com/Speeduino_manual.pdfarchive2026-10-0521806bd29ef0
4vendor_docSpeeduino wiki — V0.4 board & wiring (12v input, switched power)https://wiki.speeduino.com/en/boards/V04———
4vendor_docToyota 7M-GTE EFI manual — "Terminals of ECU" (complete terminal list, no pin numbers)http://shoarmateam.nl/upload/Toyota-Other/Cressida/MX83/efi%20system%20+%20WIRING/toyota-7m-manual-efi-fi%5b1%5d.pdf———
3forumrusEFI Mazda Miata 2002 engine wiringhttps://github.com/rusefi/rusefi/wiki/Mazda-Miata-2002archive2026-10-05cc3cae670408
2forumAllPinouts: 1989–1992 Toyota Supra ECUhttps://allpinouts.org/pinouts/connectors/car/1989-1992-toyota-supra-ecu/———