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MX-5 Miata Mazdaspeed 2004-05 (BP-ZET turbo, no VVT) → DTAFast T8+ (auto)

MX-5 Miata Mazdaspeed 2004-05 (BP-ZET turbo, no VVT) — DTAFast — T8+
⚠ NOT CHECKED. Don't build from this.
Drawn by Michael Gnankou · Rev 0 · draft · 2026-10-17

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 job61 wires · 11 connectors · 2 part lines
ToolsCrimp and extraction tools for each terminal family (see Connectors) · wire strippers · multimeter · heat gun + heat-shrink
Terminals3-1447221-4
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-2-PSP-14V-10.85☐☐☐☐☐☐☐
W2OEM-4-AFSP-14V-10.85☐☐☐☐☐☐☐
W3SP-14V-1T8-C1-310.85☐☐☐☐☐☐☐
W4OEM-4-AGT8-C3-260.85☐☐☐☐☐☐☐
W5OEM-3-ASP-GND-10.85☐☐☐☐☐☐☐
W6OEM-3-BSP-GND-10.85☐☐☐☐☐☐☐
W7OEM-4-ASP-GND-10.85☐☐☐☐☐☐☐
W8SP-GND-1T8-C1-130.85☐☐☐☐☐☐☐
W9SP-GND-1T8-C1-140.85☐☐☐☐☐☐☐
W10OEM-4-OSP-0V-10.5☐☐☐☐☐☐☐
W11SP-0V-1T8-C2-210.5☐☐☐☐☐☐☐
W12SP-0V-1T8-C2-330.5☐☐☐☐☐☐☐
W13OEM-4-LT8-C2-240.5☐☐☐☐☐☐☐
W14OEM-3-YT8-C2-120.5☐☐☐☐☐☐☐
W15OEM-3-VT8-C2-220.5☐☐☐☐☐☐☐
W16OEM-4-MT8-C3-310.5☐☐☐☐☐☐☐
W17OEM-3-FT8-C1-100.5☐☐☐☐☐☐☐
W18OEM-3-IT8-C1-180.5☐☐☐☐☐☐☐
W19OEM-2-AT8-C1-90.5☐☐☐☐☐☐☐
W20OEM-2-DT8-C1-170.5☐☐☐☐☐☐☐
W21OEM-2-GT8-C1-340.5☐☐☐☐☐☐☐
W22OEM-2-JT8-C1-250.5☐☐☐☐☐☐☐
W23OEM-4-XT8-C2-100.5☐☐☐☐☐☐☐
W24OEM-4-VT8-C2-10.5☐☐☐☐☐☐☐
W25OEM-4-PT8-C2-70.5☐☐☐☐☐☐☐
W26OEM-2-BT8-C1-50.5☐☐☐☐☐☐☐
W27OEM-2-CT8-C1-40.5☐☐☐☐☐☐☐
W28OEM-2-KT8-C1-30.5☐☐☐☐☐☐☐
W29OEM-2-MT8-C3-220.5☐☐☐☐☐☐☐
W30OEM-3-HT8-C3-230.5☐☐☐☐☐☐☐
W31OEM-2-OT8-C3-240.5☐☐☐☐☐☐☐
W32OEM-4-DRLY1-R-OUT0.5☐☐☐☐☐☐☐
W33SP-14V-1RLY1-R-IN0.5☐☐☐☐☐☐☐
W34SP-14V-1RLY1-R-COIL+0.5☐☐☐☐☐☐☐
W35RLY1-R-COIL-T8-C3-250.5☐☐☐☐☐☐☐
W36OEM-4-ERLY2-R-OUT0.5☐☐☐☐☐☐☐
W37SP-14V-1RLY2-R-IN0.5☐☐☐☐☐☐☐
W38SP-14V-1RLY2-R-COIL+0.5☐☐☐☐☐☐☐
W39RLY2-R-COIL-T8-C3-100.5☐☐☐☐☐☐☐
W40OEM-3-JT8-C3-90.5☐☐☐☐☐☐☐
W41OEM-3-PT8-C3-30.5☐☐☐☐☐☐☐
W42OEM-2-QT8-C3-40.5☐☐☐☐☐☐☐
W43OEM-2-ET8-C3-280.5☐☐☐☐☐☐☐
W44OEM-2-FT8-C1-160.5☐☐☐☐☐☐☐
W45OEM-2-HT8-C1-150.5☐☐☐☐☐☐☐
W46OEM-2-IT8-C1-240.5☐☐☐☐☐☐☐
W47OEM-2-NT8-C1-230.5☐☐☐☐☐☐☐
W48OEM-4-AET8-C2-50.5☐☐☐☐☐☐☐
W49OEM-4-AAT8-C2-60.5☐☐☐☐☐☐☐
W50OEM-4-WT8-C2-180.5☐☐☐☐☐☐☐
W51OEM-4-RT8-C2-250.5☐☐☐☐☐☐☐
W52OEM-4-NT8-C2-170.5☐☐☐☐☐☐☐
W53OEM-4-ADT8-C2-190.5☐☐☐☐☐☐☐
W54OEM-3-TT8-C2-20.5☐☐☐☐☐☐☐
W55OEM-3-ST8-C2-40.5☐☐☐☐☐☐☐
W56OEM-4-BT8-C2-80.5☐☐☐☐☐☐☐
W57OEM-4-CT8-C2-110.5☐☐☐☐☐☐☐
W58OEM-4-FT8-C2-140.5☐☐☐☐☐☐☐
W59OEM-4-HT8-C2-150.5☐☐☐☐☐☐☐
W60OEM-4-IT8-C2-270.5☐☐☐☐☐☐☐
W61OEM-4-JT8-C2-200.5☐☐☐☐☐☐☐

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
1RLY1-R-COIL+T8-C1-13open (OL)+12 V supply must not touch power ground
2RLY1-R-COIL+T8-C2-21open (OL)+12 V supply must not touch sensor ground
3RLY1-R-OUTT8-C2-21open (OL)+12 V supply must not touch sensor ground
4RLY2-R-OUTT8-C2-21open (OL)+12 V supply must not touch sensor ground
5T8-C2-24T8-C2-21open (OL)5 V sensor reference must not touch sensor ground
6T8-C3-26T8-C2-21open (OL)+12 V supply must not touch sensor ground
7RLY1-R-COIL+T8-C2-24open (OL)+12 V supply must not touch 5 V sensor reference
8RLY1-R-OUTT8-C2-24open (OL)+12 V supply must not touch 5 V sensor reference
9RLY2-R-OUTT8-C2-24open (OL)+12 V supply must not touch 5 V sensor reference
10T8-C1-13RLY1-R-OUTopen (OL)power ground must not touch +12 V supply
11T8-C1-13RLY2-R-OUTopen (OL)power ground must not touch +12 V supply
12T8-C1-13T8-C2-24open (OL)power ground must not touch 5 V sensor reference
13T8-C1-13T8-C3-26open (OL)power ground must not touch +12 V supply
14T8-C3-26T8-C2-24open (OL)+12 V supply must not touch 5 V sensor reference

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

Revisions

RevLabelByDate
No revisions yet.

Schematic

OEM-2OEM-3OEM-4RLY1-RRLY2-RSP-0VSP-14VSP-GNDT8-C1T8-C2T8-C3

Connectors

OEM-2

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
AInjector 1—W19—0.5T8-C1-9———
BCooling fan relay—W26—0.5T8-C1-5———
CCondenser fan relay—W27—0.5T8-C1-4———
DInjector 2—W20—0.5T8-C1-17———
EEGR valve—W43—0.5T8-C3-28———
FEGR valve—W44—0.5T8-C1-16———
GInjector 3—W21—0.5T8-C1-34———
HEGR valve—W45—0.5T8-C1-15———
IEGR valve—W46—0.5T8-C1-24———
JInjector 4—W22—0.5T8-C1-25———
KA/C clutch relay—W28—0.5T8-C1-3———
LNC————————
MFuel pump relay—W29—0.5T8-C3-22———
NVTCS solenoid (intake butterflies)—W47—0.5T8-C1-23———
OFuel pump relay (non-immobiliser)—W31—0.5T8-C3-24———
PISC valve +14V feed—W1—0.85SP-14V-1———
QISC valve low side—W42—0.5T8-C3-4———
RMalfunction indicator lamp (MIL)————————

OEM-3

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
APower ground—W5—0.85SP-GND-1———
BPower ground—W6—0.85SP-GND-1———
CPurge solenoid valve————————
DEGR boost solenoid————————
ENC————————
FIgnition 1 (coils 1+4, wasted spark)—W17—0.5T8-C1-10———
GNC————————
HMain relay—W30—0.5T8-C3-23———
IIgnition 2 (coils 2+3, wasted spark)—W18—0.5T8-C1-18———
JFront O2 heater—W40—0.5T8-C3-9———
KEVAP leak detection pump————————
LNC————————
MAlternator control————————
NNC————————
OTachometer output————————
PRear O2 heater—W41—0.5T8-C3-3———
QData link connector (K-line)————————
RNC————————
SImmobiliser—W55—0.5T8-C2-4———
TVehicle speed—W54—0.5T8-C2-2———
UCharge lamp————————
VCam position (CMP)—W15—0.5T8-C2-22———
WNC————————
XNC————————
YCrank position (CKP)—W14—0.5T8-C2-12———
ZNC————————

OEM-4

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
APower ground—W7—0.85SP-GND-1———
AARear O2 signal—W49—0.5T8-C2-6———
ABNC————————
ACData link connector (DLC TEN, turbo)————————
ADFuel level—W53—0.5T8-C2-19———
AEBARO/MAP sensor (turbo boost pressure)—W48—0.5T8-C2-5———
AFECU power +14V (main relay)—W2—0.85SP-14V-1———
AGConstant +12V—W4—0.85T8-C3-26———
AHEVAP leak detection pump solenoid valve————————
BBrake switch—W56—0.5T8-C2-8———
CPower steering pressure switch—W57—0.5T8-C2-11———
DBoost control solenoid (turbo)—W32—0.5RLY1-R-OUT———
EBoost control solenoid (turbo)—W36—0.5RLY2-R-OUT———
FA/C request—W58—0.5T8-C2-14———
GNC————————
HNeutral switch—W59—0.5T8-C2-15———
IClutch switch—W60—0.5T8-C2-27———
JVTCS vacuum switch—W61—0.5T8-C2-20———
KNC————————
L+5V sensor supply—W13—0.5T8-C2-24———
MKnock sensor—W16—0.5T8-C3-31———
NIntake air temperature (IAT)—W52—0.5T8-C2-17———
OSignal ground—W10—0.5SP-0V-1———
PCoolant temperature (ECT)—W25—0.5T8-C2-7———
QNC————————
RIntake air temperature 2 (IAT2, turbo)—W51—0.5T8-C2-25———
SIgnition switch (IG1) sense————————
TGenerator output voltage (terminal P)————————
UNC————————
VThrottle position (TPS)—W24—0.5T8-C2-1———
WFront O2 signal—W50—0.5T8-C2-18———
XMass air flow (MAF)—W23—0.5T8-C2-10———
YNC————————
ZTCM (automatic only)————————

RLY1-R

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
COIL+Relay coil positive (switched +12 V)—W34—0.5SP-14V-1———
COIL-Relay coil negative (ECU low-side driver)—W35—0.5T8-C3-25———
INRelay contact input (switched +12 V)—W33—0.5SP-14V-1———
OUTRelay contact output (switched +12 V to load)—W32—0.5OEM-4-D———

RLY2-R

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
COIL+Relay coil positive (switched +12 V)—W38—0.5SP-14V-1———
COIL-Relay coil negative (ECU low-side driver)—W39—0.5T8-C3-10———
INRelay contact input (switched +12 V)—W37—0.5SP-14V-1———
OUTRelay contact output (switched +12 V to load)—W36—0.5OEM-4-E———

SP-0V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W10—0.5OEM-4-O———
1——W11—0.5T8-C2-21———
1——W12—0.5T8-C2-33———

SP-14V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W1—0.85OEM-2-P———
1——W2—0.85OEM-4-AF———
1——W3—0.85T8-C1-31———
1——W33—0.5RLY1-R-IN———
1——W34—0.5RLY1-R-COIL+———
1——W37—0.5RLY2-R-IN———
1——W38—0.5RLY2-R-COIL+———

SP-GND

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W5—0.85OEM-3-A———
1——W6—0.85OEM-3-B———
1——W7—0.85OEM-4-A———
1——W8—0.85T8-C1-13———
1——W9—0.85T8-C1-14———

T8-C1

Mating face
T8-C1-1 · Coil 31T8-C1-22T8-C1-3 · PWM 33T8-C1-4 · PWM 24T8-C1-5 · PWM 15T8-C1-6 · Motor 1 +6T8-C1-7 · Motor 1 -7T8-C1-88T8-C1-9 · Injector 19T8-C1-10 · Coil 110T8-C1-11 · Coil 511T8-C1-12 · Coil 712T8-C1-13 · Power Ground 113T8-C1-14 · Power Ground 214T8-C1-15 · Injector 615T8-C1-16 · Injector 516T8-C1-17 · Injector 217T8-C1-18 · Coil 218T8-C1-19 · Coil 819T8-C1-2020T8-C1-2121T8-C1-2222T8-C1-23 · Injector 823T8-C1-24 · Injector 724T8-C1-25 · Injector 425T8-C1-26 · Coil 426T8-C1-27 · Coil 627T8-C1-2828T8-C1-2929T8-C1-3030T8-C1-31 · Ignition 12v In31T8-C1-3232T8-C1-3333T8-C1-34 · Injector 334
Wire side
T8-C1-1 · Coil 31T8-C1-22T8-C1-3 · PWM 33T8-C1-4 · PWM 24T8-C1-5 · PWM 15T8-C1-6 · Motor 1 +6T8-C1-7 · Motor 1 -7T8-C1-88T8-C1-9 · Injector 19T8-C1-10 · Coil 110T8-C1-11 · Coil 511T8-C1-12 · Coil 712T8-C1-13 · Power Ground 113T8-C1-14 · Power Ground 214T8-C1-15 · Injector 615T8-C1-16 · Injector 516T8-C1-17 · Injector 217T8-C1-18 · Coil 218T8-C1-19 · Coil 819T8-C1-2020T8-C1-2121T8-C1-2222T8-C1-23 · Injector 823T8-C1-24 · Injector 724T8-C1-25 · Injector 425T8-C1-26 · Coil 426T8-C1-27 · Coil 627T8-C1-2828T8-C1-2929T8-C1-3030T8-C1-31 · Ignition 12v In31T8-C1-3232T8-C1-3333T8-C1-34 · Injector 334
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Coil 3————————
2—————————
3PWM 3—W28—0.5OEM-2-K———
4PWM 2—W27—0.5OEM-2-C———
5PWM 1—W26—0.5OEM-2-B———
6Motor 1 +————————
7Motor 1 -————————
8—————————
9Injector 1—W19—0.5OEM-2-A———
10Coil 1—W17—0.5OEM-3-F———
11Coil 5————————
12Coil 7————————
13Power Ground 1—W8—0.85SP-GND-1———
14Power Ground 2—W9—0.85SP-GND-1———
15Injector 6—W45—0.5OEM-2-H———
16Injector 5—W44—0.5OEM-2-F———
17Injector 2—W20—0.5OEM-2-D———
18Coil 2—W18—0.5OEM-3-I———
19Coil 8————————
20—————————
21—————————
22—————————
23Injector 8—W47—0.5OEM-2-N———
24Injector 7—W46—0.5OEM-2-I———
25Injector 4—W22—0.5OEM-2-J———
26Coil 4————————
27Coil 6————————
28—————————
29—————————
30—————————
31Ignition 12v In—W3—0.85SP-14V-1———
32—————————
33—————————
34Injector 3—W21—0.5OEM-2-G———

T8-C2

Mating face
T8-C2-1 · Analogue 21T8-C2-2 · Wheel 12T8-C2-3 · Analogue 103T8-C2-4 · Digital 14T8-C2-5 · Analogue 35T8-C2-6 · Analogue 46T8-C2-7 · Thermistor 17T8-C2-8 · Digital 28T8-C2-9 · 5v Output9T8-C2-10 · Analogue 110T8-C2-11 · Digital 311T8-C2-12 · Crank12T8-C2-13 · Analogue 1213T8-C2-14 · Digital 414T8-C2-15 · Digital 515T8-C2-16 · Analogue 1116T8-C2-17 · Thermistor 317T8-C2-18 · Analogue 518T8-C2-19 · Analogue 619T8-C2-20 · Wheel 220T8-C2-21 · Sensor Ground21T8-C2-22 · Cam 122T8-C2-2323T8-C2-24 · 5v Output24T8-C2-25 · Thermistor 225T8-C2-26 · CAN High26T8-C2-27 · Digital 627T8-C2-28 · CAN Low28T8-C2-29 · Cam 229T8-C2-3030T8-C2-31 · Wheel 331T8-C2-32 · Wheel 432T8-C2-33 · Sensor Ground33T8-C2-34 · Analogue 934
Wire side
T8-C2-1 · Analogue 21T8-C2-2 · Wheel 12T8-C2-3 · Analogue 103T8-C2-4 · Digital 14T8-C2-5 · Analogue 35T8-C2-6 · Analogue 46T8-C2-7 · Thermistor 17T8-C2-8 · Digital 28T8-C2-9 · 5v Output9T8-C2-10 · Analogue 110T8-C2-11 · Digital 311T8-C2-12 · Crank12T8-C2-13 · Analogue 1213T8-C2-14 · Digital 414T8-C2-15 · Digital 515T8-C2-16 · Analogue 1116T8-C2-17 · Thermistor 317T8-C2-18 · Analogue 518T8-C2-19 · Analogue 619T8-C2-20 · Wheel 220T8-C2-21 · Sensor Ground21T8-C2-22 · Cam 122T8-C2-2323T8-C2-24 · 5v Output24T8-C2-25 · Thermistor 225T8-C2-26 · CAN High26T8-C2-27 · Digital 627T8-C2-28 · CAN Low28T8-C2-29 · Cam 229T8-C2-3030T8-C2-31 · Wheel 331T8-C2-32 · Wheel 432T8-C2-33 · Sensor Ground33T8-C2-34 · Analogue 934
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Analogue 2—W24—0.5OEM-4-V———
2Wheel 1—W54—0.5OEM-3-T———
3Analogue 10————————
4Digital 1—W55—0.5OEM-3-S———
5Analogue 3—W48—0.5OEM-4-AE———
6Analogue 4—W49—0.5OEM-4-AA———
7Thermistor 1—W25—0.5OEM-4-P———
8Digital 2—W56—0.5OEM-4-B———
95v Output————————
10Analogue 1—W23—0.5OEM-4-X———
11Digital 3—W57—0.5OEM-4-C———
12Crank—W14—0.5OEM-3-Y———
13Analogue 12————————
14Digital 4—W58—0.5OEM-4-F———
15Digital 5—W59—0.5OEM-4-H———
16Analogue 11————————
17Thermistor 3—W52—0.5OEM-4-N———
18Analogue 5—W50—0.5OEM-4-W———
19Analogue 6—W53—0.5OEM-4-AD———
20Wheel 2—W61—0.5OEM-4-J———
21Sensor Ground—W11—0.5SP-0V-1———
22Cam 1—W15—0.5OEM-3-V———
23—————————
245v Output—W13—0.5OEM-4-L———
25Thermistor 2—W51—0.5OEM-4-R———
26CAN High————————
27Digital 6—W60—0.5OEM-4-I———
28CAN Low————————
29Cam 2————————
30—————————
31Wheel 3————————
32Wheel 4————————
33Sensor Ground—W12—0.5SP-0V-1———
34Analogue 9————————

T8-C3

Mating face
T8-C3-1 · Lambda 2 Pump Current1T8-C3-2 · Lambda 2 VGND2T8-C3-3 · Lambda 2 Heater Negative3T8-C3-4 · PWM 94T8-C3-5 · Lambda 2 Trim Resistor5T8-C3-6 · Lambda 2 Nernst Voltage6T8-C3-7 · Lambda 1 Pump Current7T8-C3-8 · Lambda 1 VGND8T8-C3-9 · Lambda 1 Heater Negative9T8-C3-10 · PWM 810T8-C3-11 · Lambda 1 Trim Resistor11T8-C3-12 · Lambda 1 Nernst Voltage12T8-C3-1313T8-C3-1414T8-C3-1515T8-C3-1616T8-C3-17 · Analogue 717T8-C3-18 · Analogue 818T8-C3-1919T8-C3-2020T8-C3-2121T8-C3-22 · PWM 422T8-C3-23 · PWM 523T8-C3-24 · PWM 624T8-C3-25 · PWM 725T8-C3-26 · Permanent 12v26T8-C3-27 · Permanent 12v27T8-C3-28 · PWM 1028T8-C3-2929T8-C3-3030T8-C3-31 · Knock 131T8-C3-32 · Knock 232T8-C3-33 · CAN 2 High33T8-C3-34 · CAN 2 Low34
Wire side
T8-C3-1 · Lambda 2 Pump Current1T8-C3-2 · Lambda 2 VGND2T8-C3-3 · Lambda 2 Heater Negative3T8-C3-4 · PWM 94T8-C3-5 · Lambda 2 Trim Resistor5T8-C3-6 · Lambda 2 Nernst Voltage6T8-C3-7 · Lambda 1 Pump Current7T8-C3-8 · Lambda 1 VGND8T8-C3-9 · Lambda 1 Heater Negative9T8-C3-10 · PWM 810T8-C3-11 · Lambda 1 Trim Resistor11T8-C3-12 · Lambda 1 Nernst Voltage12T8-C3-1313T8-C3-1414T8-C3-1515T8-C3-1616T8-C3-17 · Analogue 717T8-C3-18 · Analogue 818T8-C3-1919T8-C3-2020T8-C3-2121T8-C3-22 · PWM 422T8-C3-23 · PWM 523T8-C3-24 · PWM 624T8-C3-25 · PWM 725T8-C3-26 · Permanent 12v26T8-C3-27 · Permanent 12v27T8-C3-28 · PWM 1028T8-C3-2929T8-C3-3030T8-C3-31 · Knock 131T8-C3-32 · Knock 232T8-C3-33 · CAN 2 High33T8-C3-34 · CAN 2 Low34
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Lambda 2 Pump Current————————
2Lambda 2 VGND————————
3Lambda 2 Heater Negative—W41—0.5OEM-3-P———
4PWM 9—W42—0.5OEM-2-Q———
5Lambda 2 Trim Resistor————————
6Lambda 2 Nernst Voltage————————
7Lambda 1 Pump Current————————
8Lambda 1 VGND————————
9Lambda 1 Heater Negative—W40—0.5OEM-3-J———
10PWM 8—W39—0.5RLY2-R-COIL-———
11Lambda 1 Trim Resistor————————
12Lambda 1 Nernst Voltage————————
13—————————
14—————————
15—————————
16—————————
17Analogue 7————————
18Analogue 8————————
19—————————
20—————————
21—————————
22PWM 4—W29—0.5OEM-2-M———
23PWM 5—W30—0.5OEM-3-H———
24PWM 6—W31—0.5OEM-2-O———
25PWM 7—W35—0.5RLY1-R-COIL-———
26Permanent 12v—W4—0.85OEM-4-AG———
27Permanent 12v————————
28PWM 10—W43—0.5OEM-2-E———
29—————————
30—————————
31Knock 1—W16—0.5OEM-4-M———
32Knock 2————————
33CAN 2 High————————
34CAN 2 Low————————

Pin map

OEM pointOEM functionOEM familyTarget pointTarget functionTarget familyWire colourEvidence
OEM-2-AInjector 1injector_outT8-C1-9Injector 1injector_outcorroborated
OEM-2-BCooling fan relaylow_side_outT8-C1-5PWM 1low_side_outcorroborated
OEM-2-CCondenser fan relaylow_side_outT8-C1-4PWM 2low_side_outcorroborated
OEM-2-DInjector 2injector_outT8-C1-17Injector 2injector_outcorroborated
OEM-2-EEGR valvelow_side_outT8-C3-28PWM 10low_side_outcorroborated
OEM-2-FEGR valvelow_side_outT8-C1-16Injector 5injector_outcorroborated
OEM-2-GInjector 3injector_outT8-C1-34Injector 3injector_outcorroborated
OEM-2-HEGR valvelow_side_outT8-C1-15Injector 6injector_outcorroborated
OEM-2-IEGR valvelow_side_outT8-C1-24Injector 7injector_outcorroborated
OEM-2-JInjector 4injector_outT8-C1-25Injector 4injector_outcorroborated
OEM-2-KA/C clutch relaylow_side_outT8-C1-3PWM 3low_side_outcorroborated
OEM-2-LNC————single_source
OEM-2-MFuel pump relaylow_side_outT8-C3-22PWM 4low_side_outcorroborated
OEM-2-NVTCS solenoid (intake butterflies)low_side_outT8-C1-23Injector 8injector_outcorroborated
OEM-2-OFuel pump relay (non-immobiliser)low_side_outT8-C3-24PWM 6low_side_outcorroborated
OEM-2-PISC valve +14V feedpower_inRLY1-R-COIL+ + RLY1-R-IN + RLY2-R-COIL+ + RLY2-R-IN + T8-C1-31Relay coil positive (switched +12 V) + Relay contact input (switched +12 V) + Relay coil positive (switched +12 V) + Relay contact input (switched +12 V) + Ignition 12v Inpower_in + power_outcorroborated
OEM-2-QISC valve low sidelow_side_outT8-C3-4PWM 9low_side_outcorroborated
OEM-2-RMalfunction indicator lamp (MIL)low_side_out———corroborated
OEM-3-APower groundgroundT8-C1-13 + T8-C1-14Power Ground 1 + Power Ground 2groundcorroborated
OEM-3-BPower groundgroundT8-C1-13 + T8-C1-14Power Ground 1 + Power Ground 2groundcorroborated
OEM-3-CPurge solenoid valvelow_side_out———corroborated
OEM-3-DEGR boost solenoid————conflict
OEM-3-ENC————single_source
OEM-3-FIgnition 1 (coils 1+4, wasted spark)ignition_outT8-C1-10Coil 1ignition_outcorroborated
OEM-3-GNC————single_source
OEM-3-HMain relaylow_side_outT8-C3-23PWM 5low_side_outcorroborated
OEM-3-IIgnition 2 (coils 2+3, wasted spark)ignition_outT8-C1-18Coil 2ignition_outcorroborated
OEM-3-JFront O2 heaterlow_side_outT8-C3-9Lambda 1 Heater Negativelow_side_outcorroborated
OEM-3-KEVAP leak detection pumplow_side_out———corroborated
OEM-3-LNC————single_source
OEM-3-MAlternator controllow_side_out———corroborated
OEM-3-NNC————single_source
OEM-3-OTachometer outputtacho_out———corroborated
OEM-3-PRear O2 heaterlow_side_outT8-C3-3Lambda 2 Heater Negativelow_side_outcorroborated
OEM-3-QData link connector (K-line)serial———corroborated
OEM-3-RNC————single_source
OEM-3-SImmobiliserdigital_inT8-C2-4Digital 1digital_incorroborated
OEM-3-TVehicle speeddigital_inT8-C2-2Wheel 1digital_incorroborated
OEM-3-UCharge lamplow_side_out———corroborated
OEM-3-VCam position (CMP)trigger_inT8-C2-22Cam 1trigger_incorroborated
OEM-3-WNC————single_source
OEM-3-XNC————single_source
OEM-3-YCrank position (CKP)trigger_inT8-C2-12Cranktrigger_incorroborated
OEM-3-ZNC————single_source
OEM-4-APower groundgroundT8-C1-13 + T8-C1-14Power Ground 1 + Power Ground 2groundcorroborated
OEM-4-AARear O2 signallambda_nb_inT8-C2-6Analogue 4analog_incorroborated
OEM-4-ABNC————single_source
OEM-4-ACData link connector (DLC TEN, turbo)serial———BrYsingle_source
OEM-4-ADFuel levelanalog_inT8-C2-19Analogue 6analog_incorroborated
OEM-4-AEBARO/MAP sensor (turbo boost pressure)analog_inT8-C2-5Analogue 3analog_inLYsingle_source
OEM-4-AFECU power +14V (main relay)power_inRLY1-R-COIL+ + RLY1-R-IN + RLY2-R-COIL+ + RLY2-R-IN + T8-C1-31Relay coil positive (switched +12 V) + Relay contact input (switched +12 V) + Relay coil positive (switched +12 V) + Relay contact input (switched +12 V) + Ignition 12v Inpower_in + power_outcorroborated
OEM-4-AGConstant +12Vpower_inT8-C3-26Permanent 12vpower_incorroborated
OEM-4-AHEVAP leak detection pump solenoid valvelow_side_out———corroborated
OEM-4-BBrake switchdigital_inT8-C2-8Digital 2digital_incorroborated
OEM-4-CPower steering pressure switchdigital_inT8-C2-11Digital 3digital_incorroborated
OEM-4-DBoost control solenoid (turbo)high_side_outRLY1-R-OUTRelay contact output (switched +12 V to load)power_outYsingle_source
OEM-4-EBoost control solenoid (turbo)high_side_outRLY2-R-OUTRelay contact output (switched +12 V to load)power_outYsingle_source
OEM-4-FA/C requestdigital_inT8-C2-14Digital 4digital_incorroborated
OEM-4-GNC————single_source
OEM-4-HNeutral switchdigital_inT8-C2-15Digital 5digital_incorroborated
OEM-4-IClutch switchdigital_inT8-C2-27Digital 6digital_incorroborated
OEM-4-JVTCS vacuum switchdigital_inT8-C2-20Wheel 2digital_incorroborated
OEM-4-KNC————single_source
OEM-4-L+5V sensor supplyvrefT8-C2-245v Outputvrefcorroborated
OEM-4-MKnock sensorknock_inT8-C3-31Knock 1knock_incorroborated
OEM-4-NIntake air temperature (IAT)temp_inT8-C2-17Thermistor 3temp_incorroborated
OEM-4-OSignal groundsensor_groundT8-C2-21 + T8-C2-33Sensor Ground + Sensor Groundsensor_groundcorroborated
OEM-4-PCoolant temperature (ECT)temp_inT8-C2-7Thermistor 1temp_incorroborated
OEM-4-QNC————single_source
OEM-4-RIntake air temperature 2 (IAT2, turbo)temp_inT8-C2-25Thermistor 2temp_inVYsingle_source
OEM-4-SIgnition switch (IG1) sensedigital_in———corroborated
OEM-4-TGenerator output voltage (terminal P)————corroborated
OEM-4-UNC————single_source
OEM-4-VThrottle position (TPS)analog_inT8-C2-1Analogue 2analog_incorroborated
OEM-4-WFront O2 signallambda_nb_inT8-C2-18Analogue 5analog_incorroborated
OEM-4-XMass air flow (MAF)analog_inT8-C2-10Analogue 1analog_incorroborated
OEM-4-YNC————single_source
OEM-4-ZTCM (automatic only)————corroborated

Cut list

WireFromToGauge (mm²)ColourLengthSignalIdent
W1OEM-2-PSP-14V-10.85no routeISC valve +14V feed—
W2OEM-4-AFSP-14V-10.85no routeECU power +14V (main relay)—
W3SP-14V-1T8-C1-310.85no routeIgnition 12v In—
W4OEM-4-AGT8-C3-260.85no routeConstant +12V—
W5OEM-3-ASP-GND-10.85no routePower ground—
W6OEM-3-BSP-GND-10.85no routePower ground—
W7OEM-4-ASP-GND-10.85no routePower ground—
W8SP-GND-1T8-C1-130.85no routePower Ground 1—
W9SP-GND-1T8-C1-140.85no routePower Ground 2—
W10OEM-4-OSP-0V-10.5no routeSignal ground—
W11SP-0V-1T8-C2-210.5no routeSensor Ground—
W12SP-0V-1T8-C2-330.5no routeSensor Ground—
W13OEM-4-LT8-C2-240.5no route+5V sensor supply—
W14OEM-3-YT8-C2-120.5no routeCrank position (CKP)—
W15OEM-3-VT8-C2-220.5no routeCam position (CMP)—
W16OEM-4-MT8-C3-310.5no routeKnock sensor—
W17OEM-3-FT8-C1-100.5no routeIgnition 1 (coils 1+4, wasted spark)—
W18OEM-3-IT8-C1-180.5no routeIgnition 2 (coils 2+3, wasted spark)—
W19OEM-2-AT8-C1-90.5no routeInjector 1—
W20OEM-2-DT8-C1-170.5no routeInjector 2—
W21OEM-2-GT8-C1-340.5no routeInjector 3—
W22OEM-2-JT8-C1-250.5no routeInjector 4—
W23OEM-4-XT8-C2-100.5no routeMass air flow (MAF)—
W24OEM-4-VT8-C2-10.5no routeThrottle position (TPS)—
W25OEM-4-PT8-C2-70.5no routeCoolant temperature (ECT)—
W26OEM-2-BT8-C1-50.5no routeCooling fan relay—
W27OEM-2-CT8-C1-40.5no routeCondenser fan relay—
W28OEM-2-KT8-C1-30.5no routeA/C clutch relay—
W29OEM-2-MT8-C3-220.5no routeFuel pump relay—
W30OEM-3-HT8-C3-230.5no routeMain relay—
W31OEM-2-OT8-C3-240.5no routeFuel pump relay (non-immobiliser)—
W32OEM-4-DRLY1-R-OUT0.5no routeBoost control solenoid (turbo)—
W33SP-14V-1RLY1-R-IN0.5no routeRelay contact input (switched +12 V)—
W34SP-14V-1RLY1-R-COIL+0.5no routeRelay coil positive (switched +12 V)—
W35RLY1-R-COIL-T8-C3-250.5no routeRelay coil negative (ECU low-side driver)—
W36OEM-4-ERLY2-R-OUT0.5no routeBoost control solenoid (turbo)—
W37SP-14V-1RLY2-R-IN0.5no routeRelay contact input (switched +12 V)—
W38SP-14V-1RLY2-R-COIL+0.5no routeRelay coil positive (switched +12 V)—
W39RLY2-R-COIL-T8-C3-100.5no routeRelay coil negative (ECU low-side driver)—
W40OEM-3-JT8-C3-90.5no routeFront O2 heater—
W41OEM-3-PT8-C3-30.5no routeRear O2 heater—
W42OEM-2-QT8-C3-40.5no routeISC valve low side—
W43OEM-2-ET8-C3-280.5no routeEGR valve—
W44OEM-2-FT8-C1-160.5no routeEGR valve—
W45OEM-2-HT8-C1-150.5no routeEGR valve—
W46OEM-2-IT8-C1-240.5no routeEGR valve—
W47OEM-2-NT8-C1-230.5no routeVTCS solenoid (intake butterflies)—
W48OEM-4-AET8-C2-50.5no routeBARO/MAP sensor (turbo boost pressure)—
W49OEM-4-AAT8-C2-60.5no routeRear O2 signal—
W50OEM-4-WT8-C2-180.5no routeFront O2 signal—
W51OEM-4-RT8-C2-250.5no routeIntake air temperature 2 (IAT2, turbo)—
W52OEM-4-NT8-C2-170.5no routeIntake air temperature (IAT)—
W53OEM-4-ADT8-C2-190.5no routeFuel level—
W54OEM-3-TT8-C2-20.5no routeVehicle speed—
W55OEM-3-ST8-C2-40.5no routeImmobiliser—
W56OEM-4-BT8-C2-80.5no routeBrake switch—
W57OEM-4-CT8-C2-110.5no routePower steering pressure switch—
W58OEM-4-FT8-C2-140.5no routeA/C request—
W59OEM-4-HT8-C2-150.5no routeNeutral switch—
W60OEM-4-IT8-C2-270.5no routeClutch switch—
W61OEM-4-JT8-C2-200.5no routeVTCS vacuum switch—

Bill of materials

CategoryPart numberManufacturerDescriptionQtyUnit
connector4-1437290-0TESuperseal 1.0 34-way plug, Key 13.000ea
terminal3-1447221-4TESuperseal 1.0 socket terminal, 20 AWG (0.5 sq mm)49.000ea

ECU setup sheet

RoleEngine refEngine signalSensorECU pointECU functionECU classSetup flag
No configured channels.

Findings

Open (9)

SeverityCodeSubjectMessage
errorPHYS_REQUIRED_OPENT8-C3-27T8-C3-27 "Permanent 12v" is required but not wired.
warnDATASET_GAPT8+ C110 of 34 cavities on T8+ C1 have no pin data (2,8,20,21,22,28,29,30,32,33). Anything there is invisible to these checks.
warnDATASET_GAPT8+ C22 of 34 cavities on T8+ C2 have no pin data (23,30). Anything there is invisible to these checks.
warnDATASET_GAPT8+ C39 of 34 cavities on T8+ C3 have no pin data (13,14,15,16,19,20,21,29,30). Anything there is invisible to these checks.
infoNET_FAMILYOEM-2-F ↔ T8-C1-16OEM-2-F "EGR valve" [low_side_out] is wired to T8-C1-16 "Injector 5" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-2-H ↔ T8-C1-15OEM-2-H "EGR valve" [low_side_out] is wired to T8-C1-15 "Injector 6" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-2-I ↔ T8-C1-24OEM-2-I "EGR valve" [low_side_out] is wired to T8-C1-24 "Injector 7" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-2-N ↔ T8-C1-23OEM-2-N "VTCS solenoid (intake butterflies)" [low_side_out] is wired to T8-C1-23 "Injector 8" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoUNMAPPEDOEM13 optional OEM pins are not mapped: OEM-2-R Malfunction indicator lamp (MIL); OEM-3-C Purge solenoid valve; OEM-3-D EGR boost solenoid; OEM-3-K EVAP leak detection pump; OEM-3-M Alternator control; OEM-3-O Tachometer output; OEM-3-Q Data link connector (K-line); OEM-3-U Charge lamp; OEM-4-AC Data link connector (DLC TEN, turbo); OEM-4-AH EVAP leak detection pump solenoid valve; OEM-4-S Ignition switch (IG1) sense; OEM-4-T Generator output voltage (terminal P); OEM-4-Z TCM (automatic only)

Accepted (0)

CodeSubjectReasonBy

Notes

Auto-mapped by auto_map() from the library pin data on 2026-10-17. Review every wire against both manuals before building. Open items: - T8-C3 27: Permanent 12v: required by DTAFast T8+ but no stock pin feeds it; wire by hand Not wired: - OEM-4 S: Ignition switch (IG1) sense: key-on 12 V sense — optional in a swap (the main relay is energized from keyed 12 V, not from this pin); DTAFast T8+ has no dedicated key-on input - OEM-2 R: Malfunction indicator lamp (MIL): no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T8+ - OEM-3 C: Purge solenoid valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T8+ - OEM-3 K: EVAP leak detection pump: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T8+ - OEM-3 M: Alternator control: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T8+ - OEM-3 U: Charge lamp: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T8+ - OEM-4 AH: EVAP leak detection pump solenoid valve: no free low_side/relay_control/heater_low_side/ls_hs/injector on DTAFast T8+ - OEM-3 O: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on DTAFast T8+ - OEM-3 Q: Data link connector (K-line): no free k_line on DTAFast T8+ - OEM-4 AC: Data link connector (DLC TEN, turbo): no free k_line on DTAFast T8+ - OEM-3 D: EGR boost solenoid: not classified in the library; wire by hand - OEM-4 T: Generator output voltage (terminal P): not classified in the library; wire by hand - OEM-4 Z: TCM (automatic only): not classified in the library; wire by hand

Sources

ReliabilityKindTitleURLArchiveCapturedSHA-256
4oem_manual2005 Mazda MX-5 Miata Engine Performance Control System (PCM terminal voltage reference, BP and BP WITH TC)https://trull.org/alex/pubmirror/www.mellens.net/mazda/Mazda-Miata-2005/engine_control_system.pdf———
4vendor_docAdaptronic eSel039 Select Plugin ECU for Mazda MX5 / Miata NB8B/C (OEM ECU pinout)https://www.miataturbo.net/attachments/ecus-tuning-54/04-msm-ecu-pinout-104032/nb8bc_oem_ecu_pinouts-224948d1602912806———
4vendor_docBosch relay catalogue (mini ISO relays)https://www.bosch-ibusiness.com/media/downloads/kataloge/relay/2025_10_bosch_relay_catalogue.pdfarchive2026-10-0520344cff1ef3
4vendor_docDTAFast T8+ ECU wiring diagramhttps://cdn.shopify.com/s/files/1/0848/7508/4108/files/T8PLUS_Wiring-Diagram.pdf?v=1728572013———
4community_copyHonda S2000 Service Manual 2000–2008, Fuel and Emissions Systemshttps://www.s2000.wiki/view/images/7/7f/Service_Manual_2000-2008.pdfarchive2026-10-05a470cfc928e9
4vendor_docLink G4X MX5NB2X install manual (NB2 2001-05)https://linkecu.com/documentation/MX5XNB2.pdfarchive2026-10-05741efdd9f2c8
4vendor_docOmron G8V-RH-1C7T-R-DC12 high-current micro 280 automotive relay datasheethttps://www.alldatasheet.com/datasheet-pdf/pdf/333797/OMRON/G8V-RH-1C7T-R-DC12.html—2026-10-05764a0505a941