Toyota Supra A70 1986-92 (7M-GTE) → AMP EFI MS3Pro Mini (auto)
Toyota Supra A70 1986-92 (7M-GTE) — AMP EFI — MS3Pro Mini
⚠ 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 | 2: read the Findings page before cutting any wire |
| Size of the job | 14 wires · 6 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-26 | SP-GND-1 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W2 | SP-GND-1 | MS3PROMINI-A-22 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W3 | SP-GND-1 | MS3PROMINI-A-23 | 0.85 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W4 | OEM-B-9 | SP-0V-1 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W5 | SP-0V-1 | MS3PROMINI-A-21 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W6 | OEM-A-12 | MS3PROMINI-A-10 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W7 | OEM-A-11 | MS3PROMINI-A-11 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W8 | OEM-A-25 | MS3PROMINI-A-12 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W9 | OEM-B-11 | MS3PROMINI-A-28 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W10 | OEM-B-4 | MS3PROMINI-A-26 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W11 | OEM-B-2 | MS3PROMINI-A-34 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W12 | OEM-B-6 | MS3PROMINI-A-13 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W13 | OEM-B-3 | MS3PROMINI-A-27 | 0.5 | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | ☐ | |
| W14 | OEM-D-9 | MS3PROMINI-A-35 | 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 |
|---|---|---|---|---|---|
| No supply/ground nets found to cross-check. | |||||
If any reading doesn't match, stop and get help before powering up.
Revisions
| Rev | Label | By | Date |
|---|---|---|---|
| No revisions yet. | |||
Schematic
Connectors
MS3PROMINI-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | 12V+ switched power in | — | — | — | — | — | — | — | — |
| 10 | Injector out F | — | W6 | — | 0.5 | OEM-A-12 | — | — | — |
| 11 | Injector out G | — | W7 | — | 0.5 | OEM-A-11 | — | — | — |
| 12 | Injector out H | — | W8 | — | 0.5 | OEM-A-25 | — | — | — |
| 13 | Analog in 1 | — | W12 | — | 0.5 | OEM-B-6 | — | — | — |
| 14 | Analog in 2 | — | — | — | — | — | — | — | — |
| 15 | Analog in 3 | — | — | — | — | — | — | — | — |
| 16 | Analog in 4 | — | — | — | — | — | — | — | — |
| 17 | Spark out A | — | — | — | — | — | — | — | — |
| 18 | Spark out B | — | — | — | — | — | — | — | — |
| 19 | Spark out C | — | — | — | — | — | — | — | — |
| 2 | +5V VREF out | — | — | — | — | — | — | — | — |
| 20 | Spark out D | — | — | — | — | — | — | — | — |
| 21 | Sensor ground | — | W5 | — | 0.5 | SP-0V-1 | — | — | — |
| 22 | Power ground | — | W2 | — | 0.85 | SP-GND-1 | — | — | — |
| 23 | Power ground | — | W3 | — | 0.85 | SP-GND-1 | — | — | — |
| 24 | CAN Low | — | — | — | — | — | — | — | — |
| 25 | CAN High | — | — | — | — | — | — | — | — |
| 26 | CLT in | — | W10 | — | 0.5 | OEM-B-4 | — | — | — |
| 27 | IAT in | — | W13 | — | 0.5 | OEM-B-3 | — | — | — |
| 28 | TPS in | — | W9 | — | 0.5 | OEM-B-11 | — | — | — |
| 29 | Digital switched in 1 / Flex fuel | — | — | — | — | — | — | — | — |
| 3 | PWM out 1 / Idle | — | — | — | — | — | — | — | — |
| 30 | CKP+ | — | — | — | — | — | — | — | — |
| 31 | CKP- | — | — | — | — | — | — | — | — |
| 32 | CMP+ | — | — | — | — | — | — | — | — |
| 33 | CMP- | — | — | — | — | — | — | — | — |
| 34 | Digital frequency in 1 (Hall) | — | W11 | — | 0.5 | OEM-B-2 | — | — | — |
| 35 | Digital frequency in 2 (Hall) | — | W14 | — | 0.5 | OEM-D-9 | — | — | — |
| 4 | Fuel pump out | — | — | — | — | — | — | — | — |
| 5 | Injector out A | — | — | — | — | — | — | — | — |
| 6 | Injector out B | — | — | — | — | — | — | — | — |
| 7 | Injector out C | — | — | — | — | — | — | — | — |
| 8 | Injector out D | — | — | — | — | — | — | — | — |
| 9 | Injector out E | — | — | — | — | — | — | — | — |
OEM-A
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 11 | Injectors 2 & 6 (No.20) | — | W7 | — | 0.5 | MS3PROMINI-A-11 | — | — | — |
| 12 | Injectors 1 & 4 (No.10) | — | W6 | — | 0.5 | MS3PROMINI-A-10 | — | — | — |
| 25 | Injectors 3 & 5 (No.30) | — | W8 | — | 0.5 | MS3PROMINI-A-12 | — | — | — |
| 26 | Power ground (E01/E02) | — | W1 | — | 0.85 | SP-GND-1 | — | — | — |
OEM-B
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 11 | Throttle position sensor (VTA) | — | W9 | — | 0.5 | MS3PROMINI-A-28 | — | — | — |
| 2 | Karman-vortex AFM signal (KS) | — | W11 | — | 0.5 | MS3PROMINI-A-34 | — | — | — |
| 3 | Intake air temp (THA) | — | W13 | — | 0.5 | MS3PROMINI-A-27 | — | — | — |
| 4 | Coolant temp (THW) | — | W10 | — | 0.5 | MS3PROMINI-A-26 | — | — | — |
| 6 | Primary O2 sensor (OX1) | — | W12 | — | 0.5 | MS3PROMINI-A-13 | — | — | — |
| 9 | Sensor ground (E2) | — | W4 | — | 0.5 | SP-0V-1 | — | — | — |
OEM-D
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 9 | Vehicle speed sensor (SPD) | — | W14 | — | 0.5 | MS3PROMINI-A-35 | — | — | — |
SP-0V
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W4 | — | 0.5 | OEM-B-9 | — | — | — |
| 1 | — | — | W5 | — | 0.5 | MS3PROMINI-A-21 | — | — | — |
SP-GND
| Cavity | Function | Signal | Wire | Colour | Gauge (mm²) | Destination | Terminal | Seal | Plug |
|---|---|---|---|---|---|---|---|---|---|
| 1 | — | — | W1 | — | 0.85 | OEM-A-26 | — | — | — |
| 1 | — | — | W2 | — | 0.85 | MS3PROMINI-A-22 | — | — | — |
| 1 | — | — | W3 | — | 0.85 | MS3PROMINI-A-23 | — | — | — |
Pin map
| OEM point | OEM function | OEM family | Target point | Target function | Target family | Wire colour | Evidence |
|---|---|---|---|---|---|---|---|
| OEM-A-11 | Injectors 2 & 6 (No.20) | injector_out | MS3PROMINI-A-11 | Injector out G | injector_out | corroborated | |
| OEM-A-12 | Injectors 1 & 4 (No.10) | injector_out | MS3PROMINI-A-10 | Injector out F | injector_out | corroborated | |
| OEM-A-25 | Injectors 3 & 5 (No.30) | injector_out | MS3PROMINI-A-12 | Injector out H | injector_out | corroborated | |
| OEM-A-26 | Power ground (E01/E02) | ground | MS3PROMINI-A-22 + MS3PROMINI-A-23 | Power ground + Power ground | ground | corroborated | |
| OEM-B-11 | Throttle position sensor (VTA) | analog_in | MS3PROMINI-A-28 | TPS in | analog_in | corroborated | |
| OEM-B-2 | Karman-vortex AFM signal (KS) | digital_in | MS3PROMINI-A-34 | Digital frequency in 1 (Hall) | digital_in | corroborated | |
| OEM-B-3 | Intake air temp (THA) | temp_in | MS3PROMINI-A-27 | IAT in | temp_in | corroborated | |
| OEM-B-4 | Coolant temp (THW) | temp_in | MS3PROMINI-A-26 | CLT in | temp_in | corroborated | |
| OEM-B-6 | Primary O2 sensor (OX1) | lambda_nb_in | MS3PROMINI-A-13 | Analog in 1 | analog_in | corroborated | |
| OEM-B-9 | Sensor ground (E2) | sensor_ground | MS3PROMINI-A-21 | Sensor ground | sensor_ground | corroborated | |
| OEM-D-9 | Vehicle speed sensor (SPD) | digital_in | MS3PROMINI-A-35 | Digital frequency in 2 (Hall) | digital_in | corroborated |
Cut list
| Wire | From | To | Gauge (mm²) | Colour | Length | Signal | Ident |
|---|---|---|---|---|---|---|---|
| W1 | OEM-A-26 | SP-GND-1 | 0.85 | no route | Power ground (E01/E02) | — | |
| W2 | SP-GND-1 | MS3PROMINI-A-22 | 0.85 | no route | Power ground | — | |
| W3 | SP-GND-1 | MS3PROMINI-A-23 | 0.85 | no route | Power ground | — | |
| W4 | OEM-B-9 | SP-0V-1 | 0.5 | no route | Sensor ground (E2) | — | |
| W5 | SP-0V-1 | MS3PROMINI-A-21 | 0.5 | no route | Sensor ground | — | |
| W6 | OEM-A-12 | MS3PROMINI-A-10 | 0.5 | no route | Injectors 1 & 4 (No.10) | — | |
| W7 | OEM-A-11 | MS3PROMINI-A-11 | 0.5 | no route | Injectors 2 & 6 (No.20) | — | |
| W8 | OEM-A-25 | MS3PROMINI-A-12 | 0.5 | no route | Injectors 3 & 5 (No.30) | — | |
| W9 | OEM-B-11 | MS3PROMINI-A-28 | 0.5 | no route | Throttle position sensor (VTA) | — | |
| W10 | OEM-B-4 | MS3PROMINI-A-26 | 0.5 | no route | Coolant temp (THW) | — | |
| W11 | OEM-B-2 | MS3PROMINI-A-34 | 0.5 | no route | Karman-vortex AFM signal (KS) | — | |
| W12 | OEM-B-6 | MS3PROMINI-A-13 | 0.5 | no route | Primary O2 sensor (OX1) | — | |
| W13 | OEM-B-3 | MS3PROMINI-A-27 | 0.5 | no route | Intake air temp (THA) | — | |
| W14 | OEM-D-9 | MS3PROMINI-A-35 | 0.5 | no route | Vehicle speed sensor (SPD) | — |
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 (2)
| Severity | Code | Subject | Message |
|---|---|---|---|
| error | INJECTOR_BALLAST | MS3Pro Mini | The 7M-GTE injectors (7M-GTE fuel injector) are low-impedance, but MS3Pro Mini 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 | PHYS_REQUIRED_OPEN | MS3PROMINI-A-1 | MS3PROMINI-A-1 "12V+ switched power in" is required but not wired. |
Accepted (0)
| Code | Subject | Reason | By |
|---|
Notes
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 - MS3PROMINI-A 1: 12V+ switched power in: required by AMP EFI MS3Pro Mini but no stock pin feeds it; wire by hand - Fuel-pump control: AMP EFI MS3Pro Mini needs to drive the fuel pump, but the stock ECU has no fuel-pump output (an airflow-meter contact or a separate module runs it). Add a fuel-pump relay on a spare low-side output — see the install notes for this car.
Sources
| Reliability | Kind | Title | URL | Archive | Captured | SHA-256 |
|---|---|---|---|---|---|---|
| 4 | vendor_doc | AMP EFI: MS3Pro Mini manual (fw 1.6.1) pinout & output ratings | https://cdn.shopify.com/s/files/1/0960/0014/7754/files/MS3Pro_User_Manual_Firmware_1.6.1_Mini.pdf?v=1760643335 | archive | 2026-10-05 | bed7d8ae8408 |
| 4 | vendor_doc | Toyota 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 | — | — | — |
| 2 | forum | AllPinouts: 1989–1992 Toyota Supra ECU | https://allpinouts.org/pinouts/connectors/car/1989-1992-toyota-supra-ecu/ | — | — | — |