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Lexus SC400 1992-97 (1UZ-FE non-VVTi) → AMP EFI MS3Pro Mini (auto)

Lexus SC400 1992-97 (1UZ-FE non-VVTi) — 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.

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 job38 wires · 8 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
W1OEM-A-12SP-14V-10.85☐☐☐☐☐☐☐
W2OEM-A-13SP-14V-10.85☐☐☐☐☐☐☐
W3SP-14V-1MS3PROMINI-A-10.85☐☐☐☐☐☐☐
W4OEM-A-22SP-GND-10.85☐☐☐☐☐☐☐
W5OEM-D-13SP-GND-10.85☐☐☐☐☐☐☐
W6OEM-D-26SP-GND-10.85☐☐☐☐☐☐☐
W7SP-GND-1MS3PROMINI-A-220.85☐☐☐☐☐☐☐
W8SP-GND-1MS3PROMINI-A-230.85☐☐☐☐☐☐☐
W9OEM-A-18SP-0V-10.5☐☐☐☐☐☐☐
W10OEM-C-15SP-0V-10.5☐☐☐☐☐☐☐
W11OEM-C-16SP-0V-10.5☐☐☐☐☐☐☐
W12SP-0V-1MS3PROMINI-A-210.5☐☐☐☐☐☐☐
W13OEM-A-11MS3PROMINI-A-20.5☐☐☐☐☐☐☐
W14OEM-C-8MS3PROMINI-A-300.5☐☐☐☐☐☐☐
W15OEM-C-7MS3PROMINI-A-320.5☐☐☐☐☐☐☐
W16OEM-C-6MS3PROMINI-A-330.5☐☐☐☐☐☐☐
W17OEM-C-5MS3PROMINI-A-170.5☐☐☐☐☐☐☐
W18OEM-C-13MS3PROMINI-A-180.5☐☐☐☐☐☐☐
W19OEM-D-12MS3PROMINI-A-100.5☐☐☐☐☐☐☐
W20OEM-D-11MS3PROMINI-A-110.5☐☐☐☐☐☐☐
W21OEM-D-24MS3PROMINI-A-120.5☐☐☐☐☐☐☐
W22OEM-D-25MS3PROMINI-A-50.5☐☐☐☐☐☐☐
W23OEM-A-4MS3PROMINI-A-280.5☐☐☐☐☐☐☐
W24OEM-A-5MS3PROMINI-A-260.5☐☐☐☐☐☐☐
W25OEM-B-4MS3PROMINI-A-40.5☐☐☐☐☐☐☐
W26OEM-B-6MS3PROMINI-A-30.5☐☐☐☐☐☐☐
W27OEM-B-7MS3PROMINI-A-60.5☐☐☐☐☐☐☐
W28OEM-D-19MS3PROMINI-A-70.5☐☐☐☐☐☐☐
W29OEM-D-20MS3PROMINI-A-80.5☐☐☐☐☐☐☐
W30OEM-D-17MS3PROMINI-A-90.5☐☐☐☐☐☐☐
W31OEM-A-17MS3PROMINI-A-130.5☐☐☐☐☐☐☐
W32OEM-A-6MS3PROMINI-A-140.5☐☐☐☐☐☐☐
W33OEM-B-11MS3PROMINI-A-150.5☐☐☐☐☐☐☐
W34OEM-B-24MS3PROMINI-A-160.5☐☐☐☐☐☐☐
W35OEM-A-16MS3PROMINI-A-270.5☐☐☐☐☐☐☐
W36OEM-C-2MS3PROMINI-A-340.5☐☐☐☐☐☐☐
W37OEM-C-10MS3PROMINI-A-350.5☐☐☐☐☐☐☐
W38OEM-A-19MS3PROMINI-A-290.5☐☐☐☐☐☐☐

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
1MS3PROMINI-A-1MS3PROMINI-A-21open (OL)+12 V supply must not touch sensor ground
2MS3PROMINI-A-1MS3PROMINI-A-22open (OL)+12 V supply must not touch power ground
3MS3PROMINI-A-2MS3PROMINI-A-21open (OL)5 V sensor reference must not touch sensor ground
4MS3PROMINI-A-2MS3PROMINI-A-22open (OL)5 V sensor reference must not touch power ground
5MS3PROMINI-A-2MS3PROMINI-A-1open (OL)5 V sensor reference 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

MS3PROMINI-AOEM-AOEM-BOEM-COEM-DSP-0VSP-14VSP-GND

Connectors

MS3PROMINI-A

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
112V+ switched power in—W3—0.85SP-14V-1———
10Injector out F—W19—0.5OEM-D-12———
11Injector out G—W20—0.5OEM-D-11———
12Injector out H—W21—0.5OEM-D-24———
13Analog in 1—W31—0.5OEM-A-17———
14Analog in 2—W32—0.5OEM-A-6———
15Analog in 3—W33—0.5OEM-B-11———
16Analog in 4—W34—0.5OEM-B-24———
17Spark out A—W17—0.5OEM-C-5———
18Spark out B—W18—0.5OEM-C-13———
19Spark out C————————
2+5V VREF out—W13—0.5OEM-A-11———
20Spark out D————————
21Sensor ground—W12—0.5SP-0V-1———
22Power ground—W7—0.85SP-GND-1———
23Power ground—W8—0.85SP-GND-1———
24CAN Low————————
25CAN High————————
26CLT in—W24—0.5OEM-A-5———
27IAT in—W35—0.5OEM-A-16———
28TPS in—W23—0.5OEM-A-4———
29Digital switched in 1 / Flex fuel—W38—0.5OEM-A-19———
3PWM out 1 / Idle—W26—0.5OEM-B-6———
30CKP+—W14—0.5OEM-C-8———
31CKP-————————
32CMP+—W15—0.5OEM-C-7———
33CMP-—W16—0.5OEM-C-6———
34Digital frequency in 1 (Hall)—W36—0.5OEM-C-2———
35Digital frequency in 2 (Hall)—W37—0.5OEM-C-10———
4Fuel pump out—W25—0.5OEM-B-4———
5Injector out A—W22—0.5OEM-D-25———
6Injector out B—W27—0.5OEM-B-7———
7Injector out C—W28—0.5OEM-D-19———
8Injector out D—W29—0.5OEM-D-20———
9Injector out E—W30—0.5OEM-D-17———

OEM-A

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Ignition switch (IGSW)————————
11Sensor supply +5V (VC)—W13—0.5MS3PROMINI-A-2———
12EFI main relay (B+)—W1—0.85SP-14V-1———
13EFI main relay (B1+)—W2—0.85SP-14V-1———
14Neutral start switch (NSW)————————
16Intake air temperature (THA)—W35—0.5MS3PROMINI-A-27———
17O2 right front (OXR1)—W31—0.5MS3PROMINI-A-13———
18Sensor ground (E2)—W9—0.5SP-0V-1———
19Vehicle speed (SPD)—W38—0.5MS3PROMINI-A-29———
2Starter signal (STA)————————
20Diagnostic test 2 (TE2)————————
22Power ground (E1)—W4—0.85SP-GND-1———
4Throttle position (VTA1)—W23—0.5MS3PROMINI-A-28———
5Coolant temperature (THW)—W24—0.5MS3PROMINI-A-26———
6O2 left front (OXL1)—W32—0.5MS3PROMINI-A-14———
7EGR temperature sensor————————
8Knock/shield (KS)————————
9Diagnostic test 1 (TE1)————————

OEM-B

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
11O2 right rear (OXR2)—W33—0.5MS3PROMINI-A-15———
19Stop light switch (BK)————————
20A/T kickdown switch (KD)————————
23A/C request (AC)————————
24O2 left rear (OXL2)—W34—0.5MS3PROMINI-A-16———
26Battery constant (BATT)————————
4EFI main relay control (MREL)—W25—0.5MS3PROMINI-A-4———
5Check-engine lamp (W)————————
6Fuel pump relay (FPR)—W26—0.5MS3PROMINI-A-3———
7A/C clutch relay (ACMG)—W27—0.5MS3PROMINI-A-6———
8Fuel pump control (FC)————————

OEM-C

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1TPS idle switch (IDL)————————
10Igniter 2 feedback (IGF2)—W37—0.5MS3PROMINI-A-35———
11Knock sensor 2 (KNK2)————————
12Check connector VF2————————
13Ignition 2 (IGT2)—W18—0.5MS3PROMINI-A-18———
15Cam sensor ground (G-)—W10—0.5SP-0V-1———
16Crank sensor - (NE-)—W11—0.5SP-0V-1———
2Igniter 1 feedback (IGF1)—W36—0.5MS3PROMINI-A-34———
3Knock sensor 1 (KNK1)————————
4Check connector VF1————————
5Ignition 1 (IGT1)—W17—0.5MS3PROMINI-A-17———
6Cam sensor 2 + (G2+)—W16—0.5MS3PROMINI-A-33———
7Cam sensor 1 + (G1+)—W15—0.5MS3PROMINI-A-32———
8Crank sensor + (NE+)—W14—0.5MS3PROMINI-A-30———

OEM-D

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
11Injector 2&8 (#20)—W20—0.5MS3PROMINI-A-11———
12Injector 1&7 (#10)—W19—0.5MS3PROMINI-A-10———
13Power ground (E01)—W5—0.85SP-GND-1———
17Cold start injector 1 (STJ1)—W30—0.5MS3PROMINI-A-9———
19O2 heater 2 (HT2)—W28—0.5MS3PROMINI-A-7———
20O2 heater 1 (HT1)—W29—0.5MS3PROMINI-A-8———
21EGR solenoid————————
22Fuel pressure-up VSV (PR)————————
24Injector 3&5 (#40)—W21—0.5MS3PROMINI-A-12———
25Injector 4&6 (#30)—W22—0.5MS3PROMINI-A-5———
26Power ground (E02)—W6—0.85SP-GND-1———
4Cold start injector (STJ)————————
5ISC stepper coil 4 (ISC4)————————
6ISC stepper coil 3 (ISC3)————————
7ISC stepper coil 2 (ISC2)————————
8ISC stepper coil 1 (ISC1)————————

SP-0V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W9—0.5OEM-A-18———
1——W10—0.5OEM-C-15———
1——W11—0.5OEM-C-16———
1——W12—0.5MS3PROMINI-A-21———

SP-14V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W1—0.85OEM-A-12———
1——W2—0.85OEM-A-13———
1——W3—0.85MS3PROMINI-A-1———

SP-GND

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W4—0.85OEM-A-22———
1——W5—0.85OEM-D-13———
1——W6—0.85OEM-D-26———
1——W7—0.85MS3PROMINI-A-22———
1——W8—0.85MS3PROMINI-A-23———

Pin map

OEM pointOEM functionOEM familyTarget pointTarget functionTarget familyWire colourEvidence
OEM-A-1Ignition switch (IGSW)digital_in———single_source
OEM-A-11Sensor supply +5V (VC)vrefMS3PROMINI-A-2+5V VREF outvrefsingle_source
OEM-A-12EFI main relay (B+)power_inMS3PROMINI-A-112V+ switched power inpower_insingle_source
OEM-A-13EFI main relay (B1+)power_inMS3PROMINI-A-112V+ switched power inpower_insingle_source
OEM-A-14Neutral start switch (NSW)digital_in———single_source
OEM-A-16Intake air temperature (THA)temp_inMS3PROMINI-A-27IAT intemp_insingle_source
OEM-A-17O2 right front (OXR1)lambda_nb_inMS3PROMINI-A-13Analog in 1analog_insingle_source
OEM-A-18Sensor ground (E2)sensor_groundMS3PROMINI-A-21Sensor groundsensor_groundsingle_source
OEM-A-19Vehicle speed (SPD)digital_inMS3PROMINI-A-29Digital switched in 1 / Flex fueldigital_insingle_source
OEM-A-2Starter signal (STA)digital_in———single_source
OEM-A-20Diagnostic test 2 (TE2)digital_in———single_source
OEM-A-22Power ground (E1)groundMS3PROMINI-A-22 + MS3PROMINI-A-23Power ground + Power groundgroundsingle_source
OEM-A-4Throttle position (VTA1)analog_inMS3PROMINI-A-28TPS inanalog_insingle_source
OEM-A-5Coolant temperature (THW)temp_inMS3PROMINI-A-26CLT intemp_insingle_source
OEM-A-6O2 left front (OXL1)lambda_nb_inMS3PROMINI-A-14Analog in 2analog_insingle_source
OEM-A-7EGR temperature sensortemp_in———single_source
OEM-A-8Knock/shield (KS)knock_in———single_source
OEM-A-9Diagnostic test 1 (TE1)digital_in———single_source
OEM-B-11O2 right rear (OXR2)lambda_nb_inMS3PROMINI-A-15Analog in 3analog_insingle_source
OEM-B-19Stop light switch (BK)digital_in———single_source
OEM-B-20A/T kickdown switch (KD)digital_in———single_source
OEM-B-23A/C request (AC)digital_in———single_source
OEM-B-24O2 left rear (OXL2)lambda_nb_inMS3PROMINI-A-16Analog in 4analog_insingle_source
OEM-B-26Battery constant (BATT)power_in———single_source
OEM-B-4EFI main relay control (MREL)low_side_outMS3PROMINI-A-4Fuel pump outlow_side_outsingle_source
OEM-B-5Check-engine lamp (W)low_side_out———single_source
OEM-B-6Fuel pump relay (FPR)low_side_outMS3PROMINI-A-3PWM out 1 / Idlelow_side_outsingle_source
OEM-B-7A/C clutch relay (ACMG)low_side_outMS3PROMINI-A-6Injector out Binjector_outsingle_source
OEM-B-8Fuel pump control (FC)low_side_out———single_source
OEM-C-1TPS idle switch (IDL)digital_in———single_source
OEM-C-10Igniter 2 feedback (IGF2)digital_inMS3PROMINI-A-35Digital frequency in 2 (Hall)digital_insingle_source
OEM-C-11Knock sensor 2 (KNK2)knock_in———single_source
OEM-C-12Check connector VF2analog_out———single_source
OEM-C-13Ignition 2 (IGT2)ignition_outMS3PROMINI-A-18Spark out Bignition_outsingle_source
OEM-C-15Cam sensor ground (G-)sensor_groundMS3PROMINI-A-21Sensor groundsensor_groundsingle_source
OEM-C-16Crank sensor - (NE-)sensor_groundMS3PROMINI-A-21Sensor groundsensor_groundsingle_source
OEM-C-2Igniter 1 feedback (IGF1)digital_inMS3PROMINI-A-34Digital frequency in 1 (Hall)digital_insingle_source
OEM-C-3Knock sensor 1 (KNK1)knock_in———single_source
OEM-C-4Check connector VF1analog_out———single_source
OEM-C-5Ignition 1 (IGT1)ignition_outMS3PROMINI-A-17Spark out Aignition_outsingle_source
OEM-C-6Cam sensor 2 + (G2+)trigger_inMS3PROMINI-A-33CMP-trigger_insingle_source
OEM-C-7Cam sensor 1 + (G1+)trigger_inMS3PROMINI-A-32CMP+trigger_insingle_source
OEM-C-8Crank sensor + (NE+)trigger_inMS3PROMINI-A-30CKP+trigger_insingle_source
OEM-D-11Injector 2&8 (#20)injector_outMS3PROMINI-A-11Injector out Ginjector_outsingle_source
OEM-D-12Injector 1&7 (#10)injector_outMS3PROMINI-A-10Injector out Finjector_outsingle_source
OEM-D-13Power ground (E01)groundMS3PROMINI-A-22 + MS3PROMINI-A-23Power ground + Power groundgroundsingle_source
OEM-D-17Cold start injector 1 (STJ1)low_side_outMS3PROMINI-A-9Injector out Einjector_outsingle_source
OEM-D-19O2 heater 2 (HT2)low_side_outMS3PROMINI-A-7Injector out Cinjector_outsingle_source
OEM-D-20O2 heater 1 (HT1)low_side_outMS3PROMINI-A-8Injector out Dinjector_outsingle_source
OEM-D-21EGR solenoidlow_side_out———single_source
OEM-D-22Fuel pressure-up VSV (PR)low_side_out———single_source
OEM-D-24Injector 3&5 (#40)injector_outMS3PROMINI-A-12Injector out Hinjector_outsingle_source
OEM-D-25Injector 4&6 (#30)injector_outMS3PROMINI-A-5Injector out Ainjector_outsingle_source
OEM-D-26Power ground (E02)groundMS3PROMINI-A-22 + MS3PROMINI-A-23Power ground + Power groundgroundsingle_source
OEM-D-4Cold start injector (STJ)low_side_out———single_source
OEM-D-5ISC stepper coil 4 (ISC4)low_side_out———single_source
OEM-D-6ISC stepper coil 3 (ISC3)low_side_out———single_source
OEM-D-7ISC stepper coil 2 (ISC2)low_side_out———single_source
OEM-D-8ISC stepper coil 1 (ISC1)low_side_out———single_source

Cut list

WireFromToGauge (mm²)ColourLengthSignalIdent
W1OEM-A-12SP-14V-10.85no routeEFI main relay (B+)—
W2OEM-A-13SP-14V-10.85no routeEFI main relay (B1+)—
W3SP-14V-1MS3PROMINI-A-10.85no route12V+ switched power in—
W4OEM-A-22SP-GND-10.85no routePower ground (E1)—
W5OEM-D-13SP-GND-10.85no routePower ground (E01)—
W6OEM-D-26SP-GND-10.85no routePower ground (E02)—
W7SP-GND-1MS3PROMINI-A-220.85no routePower ground—
W8SP-GND-1MS3PROMINI-A-230.85no routePower ground—
W9OEM-A-18SP-0V-10.5no routeSensor ground (E2)—
W10OEM-C-15SP-0V-10.5no routeCam sensor ground (G-)—
W11OEM-C-16SP-0V-10.5no routeCrank sensor - (NE-)—
W12SP-0V-1MS3PROMINI-A-210.5no routeSensor ground—
W13OEM-A-11MS3PROMINI-A-20.5no routeSensor supply +5V (VC)—
W14OEM-C-8MS3PROMINI-A-300.5no routeCrank sensor + (NE+)—
W15OEM-C-7MS3PROMINI-A-320.5no routeCam sensor 1 + (G1+)—
W16OEM-C-6MS3PROMINI-A-330.5no routeCam sensor 2 + (G2+)—
W17OEM-C-5MS3PROMINI-A-170.5no routeIgnition 1 (IGT1)—
W18OEM-C-13MS3PROMINI-A-180.5no routeIgnition 2 (IGT2)—
W19OEM-D-12MS3PROMINI-A-100.5no routeInjector 1&7 (#10)—
W20OEM-D-11MS3PROMINI-A-110.5no routeInjector 2&8 (#20)—
W21OEM-D-24MS3PROMINI-A-120.5no routeInjector 3&5 (#40)—
W22OEM-D-25MS3PROMINI-A-50.5no routeInjector 4&6 (#30)—
W23OEM-A-4MS3PROMINI-A-280.5no routeThrottle position (VTA1)—
W24OEM-A-5MS3PROMINI-A-260.5no routeCoolant temperature (THW)—
W25OEM-B-4MS3PROMINI-A-40.5no routeEFI main relay control (MREL)—
W26OEM-B-6MS3PROMINI-A-30.5no routeFuel pump relay (FPR)—
W27OEM-B-7MS3PROMINI-A-60.5no routeA/C clutch relay (ACMG)—
W28OEM-D-19MS3PROMINI-A-70.5no routeO2 heater 2 (HT2)—
W29OEM-D-20MS3PROMINI-A-80.5no routeO2 heater 1 (HT1)—
W30OEM-D-17MS3PROMINI-A-90.5no routeCold start injector 1 (STJ1)—
W31OEM-A-17MS3PROMINI-A-130.5no routeO2 right front (OXR1)—
W32OEM-A-6MS3PROMINI-A-140.5no routeO2 left front (OXL1)—
W33OEM-B-11MS3PROMINI-A-150.5no routeO2 right rear (OXR2)—
W34OEM-B-24MS3PROMINI-A-160.5no routeO2 left rear (OXL2)—
W35OEM-A-16MS3PROMINI-A-270.5no routeIntake air temperature (THA)—
W36OEM-C-2MS3PROMINI-A-340.5no routeIgniter 1 feedback (IGF1)—
W37OEM-C-10MS3PROMINI-A-350.5no routeIgniter 2 feedback (IGF2)—
W38OEM-A-19MS3PROMINI-A-290.5no routeVehicle speed (SPD)—

Bill of materials

CategoryPart numberManufacturerDescriptionQtyUnit

ECU setup sheet

RoleEngine refEngine signalSensorECU pointECU functionECU classSetup flag
No configured channels.

Findings

Open (6)

SeverityCodeSubjectMessage
errorREQUIRED_UNMAPPEDOEM-A-1Required OEM function "Ignition switch (IGSW)" (digital_in) is not connected to the new ECU.
infoNET_FAMILYOEM-B-7 ↔ MS3PROMINI-A-6OEM-B-7 "A/C clutch relay (ACMG)" [low_side_out] is wired to MS3PROMINI-A-6 "Injector out B" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-D-17 ↔ MS3PROMINI-A-9OEM-D-17 "Cold start injector 1 (STJ1)" [low_side_out] is wired to MS3PROMINI-A-9 "Injector out E" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-D-19 ↔ MS3PROMINI-A-7OEM-D-19 "O2 heater 2 (HT2)" [low_side_out] is wired to MS3PROMINI-A-7 "Injector out C" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-D-20 ↔ MS3PROMINI-A-8OEM-D-20 "O2 heater 1 (HT1)" [low_side_out] is wired to MS3PROMINI-A-8 "Injector out D" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoUNMAPPEDOEM23 optional OEM pins are not mapped: OEM-A-14 Neutral start switch (NSW); OEM-A-2 Starter signal (STA); OEM-A-20 Diagnostic test 2 (TE2); OEM-A-7 EGR temperature sensor; OEM-A-8 Knock/shield (KS); OEM-A-9 Diagnostic test 1 (TE1); OEM-B-19 Stop light switch (BK); OEM-B-20 A/T kickdown switch (KD); OEM-B-23 A/C request (AC); OEM-B-5 Check-engine lamp (W); OEM-B-8 Fuel pump control (FC); OEM-C-1 TPS idle switch (IDL); OEM-C-11 Knock sensor 2 (KNK2); OEM-C-12 Check connector VF2; OEM-C-3 Knock sensor 1 (KNK1); OEM-C-4 Check connector VF1; OEM-D-21 EGR solenoid; OEM-D-22 Fuel pressure-up VSV (PR); OEM-D-4 Cold start injector (STJ); OEM-D-5 ISC stepper coil 4 (ISC4); OEM-D-6 ISC stepper coil 3 (ISC3); OEM-D-7 ISC stepper coil 2 (ISC2); OEM-D-8 ISC stepper coil 1 (ISC1)

Accepted (1)

CodeSubjectReasonBy
REQUIRED_UNMAPPEDOEM-B-26Battery-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 2026-10-11. Review every wire against both manuals before building. Open items: - OEM-A 1: Ignition switch (IGSW): key-on 12 V sense — optional in a swap (the main relay is energized from keyed 12 V, not from this pin); AMP EFI MS3Pro Mini has no dedicated key-on input Not wired: - OEM-B 26: Battery constant (BATT): AMP EFI MS3Pro Mini has no battery-constant input; not needed - OEM-C 3: Knock sensor 1 (KNK1): no free knock input on AMP EFI MS3Pro Mini - OEM-C 11: Knock sensor 2 (KNK2): no free knock input on AMP EFI MS3Pro Mini - OEM-A 8: Knock/shield (KS): no free knock input on AMP EFI MS3Pro Mini - OEM-D 8: ISC stepper coil 1 (ISC1): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-D 7: ISC stepper coil 2 (ISC2): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-D 6: ISC stepper coil 3 (ISC3): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-D 5: ISC stepper coil 4 (ISC4): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-B 5: Check-engine lamp (W): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-B 8: Fuel pump control (FC): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-D 21: EGR solenoid: no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-D 22: Fuel pressure-up VSV (PR): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-D 4: Cold start injector (STJ): no free low_side/relay_control/heater_low_side/ls_hs/injector on AMP EFI MS3Pro Mini - OEM-A 7: EGR temperature sensor: no free thermistor/analog_0_5 on AMP EFI MS3Pro Mini - OEM-A 9: Diagnostic test 1 (TE1): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-A 20: Diagnostic test 2 (TE2): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-A 14: Neutral start switch (NSW): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-A 2: Starter signal (STA): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-B 19: Stop light switch (BK): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-B 20: A/T kickdown switch (KD): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-B 23: A/C request (AC): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-C 1: TPS idle switch (IDL): no free switch_in/frequency_in/analog_0_5 on AMP EFI MS3Pro Mini - OEM-C 4: Check connector VF1: no free analog_out on AMP EFI MS3Pro Mini - OEM-C 12: Check connector VF2: no free analog_out on AMP EFI MS3Pro Mini

Sources

ReliabilityKindTitleURLArchiveCapturedSHA-256
4vendor_docAMP EFI: MS3Pro Mini manual (fw 1.6.1) pinout & output ratingshttps://cdn.shopify.com/s/files/1/0960/0014/7754/files/MS3Pro_User_Manual_Firmware_1.6.1_Mini.pdf?v=1760643335archive2026-10-05bed7d8ae8408
2community_copyLextreme: Adaptronic install for 1UZ-FE (Lexus LS400/SC400) — 4-plug A/B/C/D ECU pin table (1992 LS400)https://www.lextreme.com/installation-of-an-adaptronic-ecu-for-a-lexus-ls400-sc400-1uzfe-engine/———