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MX-5 Miata NA8 1996-97 (BP-ZE, 1.8, OBD-II) → MaxxECU MaxxECU GEN2 RACE (auto)

MX-5 Miata NA8 1996-97 (BP-ZE, 1.8, OBD-II) — MaxxECU — MaxxECU GEN2 RACE
⚠ 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 job49 wires · 10 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-4-BSP-14V-10.85☐☐☐☐☐☐☐
W2SP-14V-1MAXXECUGEN2R-MX1-250.85☐☐☐☐☐☐☐
W3SP-14V-1MAXXECUGEN2R-MX2-250.85☐☐☐☐☐☐☐
W4OEM-4-ASP-GND-10.85☐☐☐☐☐☐☐
W5OEM-4-CSP-GND-10.85☐☐☐☐☐☐☐
W6OEM-4-DSP-GND-10.85☐☐☐☐☐☐☐
W7OEM-4-KSP-GND-10.85☐☐☐☐☐☐☐
W8SP-GND-1MAXXECUGEN2R-MX1-90.85☐☐☐☐☐☐☐
W9SP-GND-1MAXXECUGEN2R-MX2-90.85☐☐☐☐☐☐☐
W10SP-GND-1MAXXECUGEN2R-MX3-90.85☐☐☐☐☐☐☐
W11OEM-3-OSP-0V-10.5☐☐☐☐☐☐☐
W12OEM-4-HSP-0V-10.5☐☐☐☐☐☐☐
W13SP-0V-1MAXXECUGEN2R-MX1-140.5☐☐☐☐☐☐☐
W14OEM-3-IMAXXECUGEN2R-MX1-120.5☐☐☐☐☐☐☐
W15OEM-4-EMAXXECUGEN2R-MX1-100.5☐☐☐☐☐☐☐
W16OEM-4-GMAXXECUGEN2R-MX1-180.5☐☐☐☐☐☐☐
W17OEM-4-NMAXXECUGEN2R-MX1-10.5☐☐☐☐☐☐☐
W18OEM-4-RMAXXECUGEN2R-MX1-20.5☐☐☐☐☐☐☐
W19OEM-4-UMAXXECUGEN2R-MX1-310.5☐☐☐☐☐☐☐
W20OEM-4-VMAXXECUGEN2R-MX1-320.5☐☐☐☐☐☐☐
W21OEM-4-WMAXXECUGEN2R-MX1-330.5☐☐☐☐☐☐☐
W22OEM-4-XMAXXECUGEN2R-MX1-340.5☐☐☐☐☐☐☐
W23OEM-3-BMAXXECUGEN2R-MX1-260.5☐☐☐☐☐☐☐
W24OEM-3-FMAXXECUGEN2R-MX1-270.5☐☐☐☐☐☐☐
W25OEM-3-GMAXXECUGEN2R-MX1-280.5☐☐☐☐☐☐☐
W26OEM-1-AMAXXECUGEN2R-MX1-50.5☐☐☐☐☐☐☐
W27OEM-1-BMAXXECUGEN2R-MX1-60.5☐☐☐☐☐☐☐
W28OEM-1-GMAXXECUGEN2R-MX1-70.5☐☐☐☐☐☐☐
W29OEM-1-UMAXXECUGEN2R-MX1-80.5☐☐☐☐☐☐☐
W30OEM-3-MMAXXECUGEN2R-MX2-120.5☐☐☐☐☐☐☐
W31OEM-1-EMAXXECUGEN2R-MX1-170.5☐☐☐☐☐☐☐
W32OEM-4-JMAXXECUGEN2R-MX2-30.5☐☐☐☐☐☐☐
W33OEM-4-OMAXXECUGEN2R-MX3-120.5☐☐☐☐☐☐☐
W34OEM-4-PMAXXECUGEN2R-MX2-330.5☐☐☐☐☐☐☐
W35OEM-4-QMAXXECUGEN2R-MX2-340.5☐☐☐☐☐☐☐
W36OEM-4-TMAXXECUGEN2R-MX3-290.5☐☐☐☐☐☐☐
W37OEM-3-HMAXXECUGEN2R-MX1-290.5☐☐☐☐☐☐☐
W38OEM-3-NMAXXECUGEN2R-MX1-300.5☐☐☐☐☐☐☐
W39OEM-3-CMAXXECUGEN2R-MX2-40.5☐☐☐☐☐☐☐
W40OEM-3-DMAXXECUGEN2R-MX2-50.5☐☐☐☐☐☐☐
W41OEM-3-KMAXXECUGEN2R-MX2-60.5☐☐☐☐☐☐☐
W42OEM-3-JMAXXECUGEN2R-MX2-130.5☐☐☐☐☐☐☐
W43OEM-1-MMAXXECUGEN2R-MX1-230.5☐☐☐☐☐☐☐
W44OEM-1-CMAXXECUGEN2R-MX1-240.5☐☐☐☐☐☐☐
W45OEM-1-KMAXXECUGEN2R-MX4-30.5☐☐☐☐☐☐☐
W46OEM-1-LMAXXECUGEN2R-MX4-60.5☐☐☐☐☐☐☐
W47OEM-1-QMAXXECUGEN2R-MX4-90.5☐☐☐☐☐☐☐
W48OEM-3-LMAXXECUGEN2R-MX4-280.5☐☐☐☐☐☐☐
W49OEM-3-PMAXXECUGEN2R-MX2-140.5☐☐☐☐☐☐☐

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
1MAXXECUGEN2R-MX1-12MAXXECUGEN2R-MX1-14open (OL)5 V sensor reference must not touch sensor ground
2MAXXECUGEN2R-MX1-12MAXXECUGEN2R-MX1-9open (OL)5 V sensor reference must not touch power ground
3MAXXECUGEN2R-MX1-12MAXXECUGEN2R-MX1-25open (OL)5 V sensor reference must not touch +12 V supply
4MAXXECUGEN2R-MX1-14MAXXECUGEN2R-MX1-25open (OL)sensor ground must not touch +12 V supply
5MAXXECUGEN2R-MX1-9MAXXECUGEN2R-MX1-25open (OL)power 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

MAXXECUGEN2R-MX1MAXXECUGEN2R-MX2MAXXECUGEN2R-MX3MAXXECUGEN2R-MX4OEM-1OEM-3OEM-4SP-0VSP-14VSP-GND

Connectors

MAXXECUGEN2R-MX1

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Ignition 1—W17—0.5OEM-4-N———
10Digital/VR 1 SIGNAL +—W15—0.5OEM-4-E———
11Digital/VR 1 SIGNAL -————————
12Digital/VR 1 POWER SUPPLY—W14—0.5OEM-3-I———
13Digital/VR 1 SHIELD————————
14SENSOR GND—W13—0.5SP-0V-1———
15CAN L————————
16CAN H————————
17GP out 5 (GND)—W31—0.5OEM-1-E———
18Digital/VR 2 SIGNAL +—W16—0.5OEM-4-G———
19Digital/VR 2 SIGNAL -————————
2Ignition 2—W18—0.5OEM-4-R———
20Digital/VR 2 POWER SUPPLY————————
21Digital/VR 2 SHIELD————————
225V power supply————————
23Digital/VR 3 SIGNAL +—W43—0.5OEM-1-M———
24Digital/VR 4 SIGNAL +—W44—0.5OEM-1-C———
2512V supply 1—W2—0.85SP-14V-1———
26AIN 1—W23—0.5OEM-3-B———
27AIN 2—W24—0.5OEM-3-F———
28AIN 3—W25—0.5OEM-3-G———
29AIN 4—W37—0.5OEM-3-H———
3Ignition 3————————
30AIN 5—W38—0.5OEM-3-N———
31INJECTOR 1—W19—0.5OEM-4-U———
32INJECTOR 2—W20—0.5OEM-4-V———
33INJECTOR 3—W21—0.5OEM-4-W———
34INJECTOR 4—W22—0.5OEM-4-X———
4Ignition 4————————
5GP out 1 (GND)—W26—0.5OEM-1-A———
6GP out 2 (GND)—W27—0.5OEM-1-B———
7GP out 3 (GND)—W28—0.5OEM-1-G———
8GP out 4 (GND)—W29—0.5OEM-1-U———
9Engine gnd—W8—0.85SP-GND-1———

MAXXECUGEN2R-MX2

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Ignition 5————————
10WBO2 Sensor 1 VS————————
11WBO2 Sensor 1 COM/VREF————————
12GP OUT 7 / WBO2 Sensor 1 H-—W30—0.5OEM-3-M———
13AIN 9—W42—0.5OEM-3-J———
14AIN 10—W49—0.5OEM-3-P———
15AIN 11————————
16AIN 12————————
17AIN 13————————
18WBO2 sensor 1 RCAL————————
19WBO2 sensor 1 IP————————
2Ignition 6————————
2012V WBO2 sensor 1 H+————————
21WBO2 sensor 1 SHIELD————————
22AIN 14————————
23AIN 15————————
2412V supply 3————————
2512V supply 2—W3—0.85SP-14V-1———
26KNOCK1 SHIELD————————
27KNOCK 1-————————
28KNOCK 1+————————
29KNOCK 2 SHIELD————————
3GP out 6 (GND)—W32—0.5OEM-4-J———
30KNOCK 2-————————
31KNOCK 2+————————
32AIN 16————————
33INJECTOR 5—W34—0.5OEM-4-P———
34INJECTOR 6—W35—0.5OEM-4-Q———
4AIN 6—W39—0.5OEM-3-C———
5AIN 7—W40—0.5OEM-3-D———
6AIN 8—W41—0.5OEM-3-K———
7GP out 13 (H-BRIDGE 1)————————
8GP out 14 (H-BRIDGE 1)————————
9Engine gnd—W9—0.85SP-GND-1———

MAXXECUGEN2R-MX3

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1GP out 15 (H-BRIDGE 2)————————
10WBO2 sensor 2 VS————————
11WBO2 sensor 2 COM/VREF————————
12GP Out 8 (GND) / WBO2 Sensor 2 H-—W33—0.5OEM-4-O———
13WBO2 sensor 2 SHIELD————————
14GP OUT 9 (12V)————————
15GP OUT 10 (12V)————————
16GP OUT 11 (12V)————————
17GP OUT 12 (12V)————————
18WBO2 sensor 2 RCAL————————
19WBO2 sensor 2 IP————————
2GP out 16 (H-BRIDGE 2)————————
2012V WBO2 sensor 2 (H+)————————
21AIN 17————————
22AIN 18————————
23AIN 19————————
24AIN 20————————
25AIN 21————————
26AIN 22————————
27AIN 23————————
28AIN 24————————
29INJECTOR 7—W36—0.5OEM-4-T———
3Ignition 7————————
30INJECTOR 8————————
31INJECTOR 9————————
32INJECTOR 10————————
33INJECTOR 11————————
34INJECTOR 12————————
4Ignition 8————————
5Ignition 9————————
6Ignition 10————————
7Ignition 11————————
8Ignition 12————————
9Engine gnd—W10—0.85SP-GND-1———

MAXXECUGEN2R-MX4

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Digital/VR 5 SHIELD————————
10EGT 1 +————————
11EGT 2 +————————
12EGT 3 +————————
13EGT 4 +————————
14EGT 5 +————————
15EGT 6 +————————
16EGT 7 +————————
17EGT 8 +————————
18EGT 1 -————————
19EGT 2 -————————
2Digital/VR 5 SIGNAL -————————
20EGT 3 -————————
21EGT 4 -————————
22EGT 5 -————————
23EGT 6 -————————
24EGT 7 -————————
25EGT 8 -————————
26Digital/VR 8 SHIELD————————
27Digital/VR 8 SIGNAL -————————
28Digital/VR 8 SIGNAL +—W48—0.5OEM-3-L———
29CAN 2 L————————
3Digital/VR 5 SIGNAL +—W45—0.5OEM-1-K———
30CAN 2 H————————
31INJECTOR 13————————
32INJECTOR 14————————
33INJECTOR 15————————
34INJECTOR 16————————
4Digital/VR 6 SHIELD————————
5Digital/VR 6 SIGNAL -————————
6Digital/VR 6 SIGNAL +—W46—0.5OEM-1-L———
7Digital/VR 7 SHIELD————————
8Digital/VR 7 SIGNAL -————————
9Digital/VR 7 SIGNAL +—W47—0.5OEM-1-Q———

OEM-1

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
ACooling fan relay (low-side)—W26—0.5MAXXECUGEN2R-MX1-5———
BA/C condenser fan relay—W27—0.5MAXXECUGEN2R-MX1-6———
CStarter input (12V while cranking)—W44—0.5MAXXECUGEN2R-MX1-24———
ECheck engine light (MIL)—W31—0.5MAXXECUGEN2R-MX1-17———
GA/C clutch relay—W28—0.5MAXXECUGEN2R-MX1-7———
KA/C pressure switch (A/C request)—W45—0.5MAXXECUGEN2R-MX4-3———
LClutch switch—W46—0.5MAXXECUGEN2R-MX4-6———
MVehicle speed sensor (VSS)—W43—0.5MAXXECUGEN2R-MX1-23———
QBrake switch—W47—0.5MAXXECUGEN2R-MX4-9———
UFuel pump relay (low-side)—W29—0.5MAXXECUGEN2R-MX1-8———

OEM-3

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
BMAF sensor input—W23—0.5MAXXECUGEN2R-MX1-26———
CFront O2 sensor input—W39—0.5MAXXECUGEN2R-MX2-4———
DRear O2 sensor input—W40—0.5MAXXECUGEN2R-MX2-5———
FThrottle position (TPS)—W24—0.5MAXXECUGEN2R-MX1-27———
GEngine coolant temp (CLT)—W25—0.5MAXXECUGEN2R-MX1-28———
HEGR boost sensor—W37—0.5MAXXECUGEN2R-MX1-29———
I+5V sensor reference—W14—0.5MAXXECUGEN2R-MX1-12———
JEGR valve position sensor—W42—0.5MAXXECUGEN2R-MX2-13———
KIntake air temp (IAT)—W41—0.5MAXXECUGEN2R-MX2-6———
LIdle switch (closed throttle)—W48—0.5MAXXECUGEN2R-MX4-28———
MFront O2 heater control—W30—0.5MAXXECUGEN2R-MX2-12———
NEGR boost sensor (2nd channel)—W38—0.5MAXXECUGEN2R-MX1-30———
OSensor ground—W11—0.5SP-0V-1———
PPower steering pressure switch—W49—0.5MAXXECUGEN2R-MX2-14———

OEM-4

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
AChassis ground—W4—0.85SP-GND-1———
BECU power +12V (main relay)—W1—0.85SP-14V-1———
CChassis ground—W5—0.85SP-GND-1———
DChassis ground—W6—0.85SP-GND-1———
ECrank position (CKP) sensor—W15—0.5MAXXECUGEN2R-MX1-10———
FCAS SGT (cam trigger)————————
GCAS SGC (cam sync)—W16—0.5MAXXECUGEN2R-MX1-18———
HCrank pickup timing ground (CKP gnd)—W12—0.5SP-0V-1———
IPermanent +12V (battery)————————
JPRC solenoid (FPR control)—W32—0.5MAXXECUGEN2R-MX2-3———
KChassis ground—W7—0.85SP-GND-1———
LTachometer output————————
NIgnition coil trigger (cyl 1&4)—W17—0.5MAXXECUGEN2R-MX1-1———
OEGR vent solenoid—W33—0.5MAXXECUGEN2R-MX3-12———
PEGR vacuum solenoid—W34—0.5MAXXECUGEN2R-MX2-33———
QIdle air control (IAC) valve—W35—0.5MAXXECUGEN2R-MX2-34———
RIgnition coil trigger (cyl 2&3)—W18—0.5MAXXECUGEN2R-MX1-2———
TEVAP purge solenoid—W36—0.5MAXXECUGEN2R-MX3-29———
UInjector 1 (cyl 1)—W19—0.5MAXXECUGEN2R-MX1-31———
VInjector 2 (cyl 2)—W20—0.5MAXXECUGEN2R-MX1-32———
WInjector 3 (cyl 3)—W21—0.5MAXXECUGEN2R-MX1-33———
XInjector 4 (cyl 4)—W22—0.5MAXXECUGEN2R-MX1-34———

SP-0V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W11—0.5OEM-3-O———
1——W12—0.5OEM-4-H———
1——W13—0.5MAXXECUGEN2R-MX1-14———

SP-14V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W1—0.85OEM-4-B———
1——W2—0.85MAXXECUGEN2R-MX1-25———
1——W3—0.85MAXXECUGEN2R-MX2-25———

SP-GND

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W4—0.85OEM-4-A———
1——W5—0.85OEM-4-C———
1——W6—0.85OEM-4-D———
1——W7—0.85OEM-4-K———
1——W8—0.85MAXXECUGEN2R-MX1-9———
1——W9—0.85MAXXECUGEN2R-MX2-9———
1——W10—0.85MAXXECUGEN2R-MX3-9———

Pin map

OEM pointOEM functionOEM familyTarget pointTarget functionTarget familyWire colourEvidence
OEM-1-ACooling fan relay (low-side)low_side_outMAXXECUGEN2R-MX1-5GP out 1 (GND)low_side_outcorroborated
OEM-1-BA/C condenser fan relaylow_side_outMAXXECUGEN2R-MX1-6GP out 2 (GND)low_side_outcorroborated
OEM-1-CStarter input (12V while cranking)digital_inMAXXECUGEN2R-MX1-24Digital/VR 4 SIGNAL +digital_incorroborated
OEM-1-ECheck engine light (MIL)low_side_outMAXXECUGEN2R-MX1-17GP out 5 (GND)low_side_outcorroborated
OEM-1-GA/C clutch relaylow_side_outMAXXECUGEN2R-MX1-7GP out 3 (GND)low_side_outcorroborated
OEM-1-KA/C pressure switch (A/C request)digital_inMAXXECUGEN2R-MX4-3Digital/VR 5 SIGNAL +digital_incorroborated
OEM-1-LClutch switchdigital_inMAXXECUGEN2R-MX4-6Digital/VR 6 SIGNAL +digital_incorroborated
OEM-1-MVehicle speed sensor (VSS)digital_inMAXXECUGEN2R-MX1-23Digital/VR 3 SIGNAL +digital_incorroborated
OEM-1-QBrake switchdigital_inMAXXECUGEN2R-MX4-9Digital/VR 7 SIGNAL +digital_incorroborated
OEM-1-UFuel pump relay (low-side)low_side_outMAXXECUGEN2R-MX1-8GP out 4 (GND)low_side_outcorroborated
OEM-3-BMAF sensor inputanalog_inMAXXECUGEN2R-MX1-26AIN 1analog_incorroborated
OEM-3-CFront O2 sensor inputlambda_nb_inMAXXECUGEN2R-MX2-4AIN 6analog_incorroborated
OEM-3-DRear O2 sensor inputlambda_nb_inMAXXECUGEN2R-MX2-5AIN 7analog_incorroborated
OEM-3-FThrottle position (TPS)analog_inMAXXECUGEN2R-MX1-27AIN 2analog_incorroborated
OEM-3-GEngine coolant temp (CLT)temp_inMAXXECUGEN2R-MX1-28AIN 3analog_incorroborated
OEM-3-HEGR boost sensoranalog_inMAXXECUGEN2R-MX1-29AIN 4analog_incorroborated
OEM-3-I+5V sensor referencevrefMAXXECUGEN2R-MX1-12Digital/VR 1 POWER SUPPLYvrefcorroborated
OEM-3-JEGR valve position sensoranalog_inMAXXECUGEN2R-MX2-13AIN 9analog_incorroborated
OEM-3-KIntake air temp (IAT)temp_inMAXXECUGEN2R-MX2-6AIN 8analog_incorroborated
OEM-3-LIdle switch (closed throttle)digital_inMAXXECUGEN2R-MX4-28Digital/VR 8 SIGNAL +digital_incorroborated
OEM-3-MFront O2 heater controllow_side_outMAXXECUGEN2R-MX2-12GP OUT 7 / WBO2 Sensor 1 H-low_side_outcorroborated
OEM-3-NEGR boost sensor (2nd channel)analog_inMAXXECUGEN2R-MX1-30AIN 5analog_incorroborated
OEM-3-OSensor groundsensor_groundMAXXECUGEN2R-MX1-14SENSOR GNDsensor_groundcorroborated
OEM-3-PPower steering pressure switchdigital_inMAXXECUGEN2R-MX2-14AIN 10analog_incorroborated
OEM-4-AChassis groundgroundMAXXECUGEN2R-MX1-9 + MAXXECUGEN2R-MX2-9 + MAXXECUGEN2R-MX3-9Engine gnd + Engine gnd + Engine gndgroundcorroborated
OEM-4-BECU power +12V (main relay)power_inMAXXECUGEN2R-MX1-25 + MAXXECUGEN2R-MX2-2512V supply 1 + 12V supply 2power_incorroborated
OEM-4-CChassis groundgroundMAXXECUGEN2R-MX1-9 + MAXXECUGEN2R-MX2-9 + MAXXECUGEN2R-MX3-9Engine gnd + Engine gnd + Engine gndgroundcorroborated
OEM-4-DChassis groundgroundMAXXECUGEN2R-MX1-9 + MAXXECUGEN2R-MX2-9 + MAXXECUGEN2R-MX3-9Engine gnd + Engine gnd + Engine gndgroundcorroborated
OEM-4-ECrank position (CKP) sensortrigger_inMAXXECUGEN2R-MX1-10Digital/VR 1 SIGNAL +trigger_incorroborated
OEM-4-FCAS SGT (cam trigger)trigger_in———corroborated
OEM-4-GCAS SGC (cam sync)trigger_inMAXXECUGEN2R-MX1-18Digital/VR 2 SIGNAL +trigger_incorroborated
OEM-4-HCrank pickup timing ground (CKP gnd)sensor_groundMAXXECUGEN2R-MX1-14SENSOR GNDsensor_groundcorroborated
OEM-4-IPermanent +12V (battery)power_in———corroborated
OEM-4-JPRC solenoid (FPR control)low_side_outMAXXECUGEN2R-MX2-3GP out 6 (GND)low_side_outcorroborated
OEM-4-KChassis groundgroundMAXXECUGEN2R-MX1-9 + MAXXECUGEN2R-MX2-9 + MAXXECUGEN2R-MX3-9Engine gnd + Engine gnd + Engine gndgroundcorroborated
OEM-4-LTachometer outputtacho_out———corroborated
OEM-4-NIgnition coil trigger (cyl 1&4)ignition_outMAXXECUGEN2R-MX1-1Ignition 1ignition_outcorroborated
OEM-4-OEGR vent solenoidlow_side_outMAXXECUGEN2R-MX3-12GP Out 8 (GND) / WBO2 Sensor 2 H-low_side_outcorroborated
OEM-4-PEGR vacuum solenoidlow_side_outMAXXECUGEN2R-MX2-33INJECTOR 5injector_outcorroborated
OEM-4-QIdle air control (IAC) valvelow_side_outMAXXECUGEN2R-MX2-34INJECTOR 6injector_outcorroborated
OEM-4-RIgnition coil trigger (cyl 2&3)ignition_outMAXXECUGEN2R-MX1-2Ignition 2ignition_outcorroborated
OEM-4-TEVAP purge solenoidlow_side_outMAXXECUGEN2R-MX3-29INJECTOR 7injector_outcorroborated
OEM-4-UInjector 1 (cyl 1)injector_outMAXXECUGEN2R-MX1-31INJECTOR 1injector_outcorroborated
OEM-4-VInjector 2 (cyl 2)injector_outMAXXECUGEN2R-MX1-32INJECTOR 2injector_outcorroborated
OEM-4-WInjector 3 (cyl 3)injector_outMAXXECUGEN2R-MX1-33INJECTOR 3injector_outcorroborated
OEM-4-XInjector 4 (cyl 4)injector_outMAXXECUGEN2R-MX1-34INJECTOR 4injector_outcorroborated

Cut list

WireFromToGauge (mm²)ColourLengthSignalIdent
W1OEM-4-BSP-14V-10.85no routeECU power +12V (main relay)—
W2SP-14V-1MAXXECUGEN2R-MX1-250.85no route12V supply 1—
W3SP-14V-1MAXXECUGEN2R-MX2-250.85no route12V supply 2—
W4OEM-4-ASP-GND-10.85no routeChassis ground—
W5OEM-4-CSP-GND-10.85no routeChassis ground—
W6OEM-4-DSP-GND-10.85no routeChassis ground—
W7OEM-4-KSP-GND-10.85no routeChassis ground—
W8SP-GND-1MAXXECUGEN2R-MX1-90.85no routeEngine gnd—
W9SP-GND-1MAXXECUGEN2R-MX2-90.85no routeEngine gnd—
W10SP-GND-1MAXXECUGEN2R-MX3-90.85no routeEngine gnd—
W11OEM-3-OSP-0V-10.5no routeSensor ground—
W12OEM-4-HSP-0V-10.5no routeCrank pickup timing ground (CKP gnd)—
W13SP-0V-1MAXXECUGEN2R-MX1-140.5no routeSENSOR GND—
W14OEM-3-IMAXXECUGEN2R-MX1-120.5no route+5V sensor reference—
W15OEM-4-EMAXXECUGEN2R-MX1-100.5no routeCrank position (CKP) sensor—
W16OEM-4-GMAXXECUGEN2R-MX1-180.5no routeCAS SGC (cam sync)—
W17OEM-4-NMAXXECUGEN2R-MX1-10.5no routeIgnition coil trigger (cyl 1&4)—
W18OEM-4-RMAXXECUGEN2R-MX1-20.5no routeIgnition coil trigger (cyl 2&3)—
W19OEM-4-UMAXXECUGEN2R-MX1-310.5no routeInjector 1 (cyl 1)—
W20OEM-4-VMAXXECUGEN2R-MX1-320.5no routeInjector 2 (cyl 2)—
W21OEM-4-WMAXXECUGEN2R-MX1-330.5no routeInjector 3 (cyl 3)—
W22OEM-4-XMAXXECUGEN2R-MX1-340.5no routeInjector 4 (cyl 4)—
W23OEM-3-BMAXXECUGEN2R-MX1-260.5no routeMAF sensor input—
W24OEM-3-FMAXXECUGEN2R-MX1-270.5no routeThrottle position (TPS)—
W25OEM-3-GMAXXECUGEN2R-MX1-280.5no routeEngine coolant temp (CLT)—
W26OEM-1-AMAXXECUGEN2R-MX1-50.5no routeCooling fan relay (low-side)—
W27OEM-1-BMAXXECUGEN2R-MX1-60.5no routeA/C condenser fan relay—
W28OEM-1-GMAXXECUGEN2R-MX1-70.5no routeA/C clutch relay—
W29OEM-1-UMAXXECUGEN2R-MX1-80.5no routeFuel pump relay (low-side)—
W30OEM-3-MMAXXECUGEN2R-MX2-120.5no routeFront O2 heater control—
W31OEM-1-EMAXXECUGEN2R-MX1-170.5no routeCheck engine light (MIL)—
W32OEM-4-JMAXXECUGEN2R-MX2-30.5no routePRC solenoid (FPR control)—
W33OEM-4-OMAXXECUGEN2R-MX3-120.5no routeEGR vent solenoid—
W34OEM-4-PMAXXECUGEN2R-MX2-330.5no routeEGR vacuum solenoid—
W35OEM-4-QMAXXECUGEN2R-MX2-340.5no routeIdle air control (IAC) valve—
W36OEM-4-TMAXXECUGEN2R-MX3-290.5no routeEVAP purge solenoid—
W37OEM-3-HMAXXECUGEN2R-MX1-290.5no routeEGR boost sensor—
W38OEM-3-NMAXXECUGEN2R-MX1-300.5no routeEGR boost sensor (2nd channel)—
W39OEM-3-CMAXXECUGEN2R-MX2-40.5no routeFront O2 sensor input—
W40OEM-3-DMAXXECUGEN2R-MX2-50.5no routeRear O2 sensor input—
W41OEM-3-KMAXXECUGEN2R-MX2-60.5no routeIntake air temp (IAT)—
W42OEM-3-JMAXXECUGEN2R-MX2-130.5no routeEGR valve position sensor—
W43OEM-1-MMAXXECUGEN2R-MX1-230.5no routeVehicle speed sensor (VSS)—
W44OEM-1-CMAXXECUGEN2R-MX1-240.5no routeStarter input (12V while cranking)—
W45OEM-1-KMAXXECUGEN2R-MX4-30.5no routeA/C pressure switch (A/C request)—
W46OEM-1-LMAXXECUGEN2R-MX4-60.5no routeClutch switch—
W47OEM-1-QMAXXECUGEN2R-MX4-90.5no routeBrake switch—
W48OEM-3-LMAXXECUGEN2R-MX4-280.5no routeIdle switch (closed throttle)—
W49OEM-3-PMAXXECUGEN2R-MX2-140.5no routePower steering pressure switch—

Bill of materials

CategoryPart numberManufacturerDescriptionQtyUnit

ECU setup sheet

RoleEngine refEngine signalSensorECU pointECU functionECU classSetup flag
No configured channels.

Findings

Open (8)

SeverityCodeSubjectMessage
errorREQUIRED_UNMAPPEDOEM-4-FRequired OEM function "CAS SGT (cam trigger)" (trigger_in) is not connected to the new ECU.
warnNET_FAMILYOEM-3-P ↔ MAXXECUGEN2R-MX2-14OEM-3-P "Power steering pressure switch" [digital_in] is wired to MAXXECUGEN2R-MX2-14 "AIN 10" [analog_in]. Analog and digital on one net. A switch on an analog input works with a pull-up and a threshold; an analog sensor on a digital input loses its value.
infoNET_FAMILYOEM-3-G ↔ MAXXECUGEN2R-MX1-28OEM-3-G "Engine coolant temp (CLT)" [temp_in] is wired to MAXXECUGEN2R-MX1-28 "AIN 3" [analog_in]. Thermistor on a plain analog input needs a pull-up; check the channel can enable one.
infoNET_FAMILYOEM-3-K ↔ MAXXECUGEN2R-MX2-6OEM-3-K "Intake air temp (IAT)" [temp_in] is wired to MAXXECUGEN2R-MX2-6 "AIN 8" [analog_in]. Thermistor on a plain analog input needs a pull-up; check the channel can enable one.
infoNET_FAMILYOEM-4-P ↔ MAXXECUGEN2R-MX2-33OEM-4-P "EGR vacuum solenoid" [low_side_out] is wired to MAXXECUGEN2R-MX2-33 "INJECTOR 5" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-4-Q ↔ MAXXECUGEN2R-MX2-34OEM-4-Q "Idle air control (IAC) valve" [low_side_out] is wired to MAXXECUGEN2R-MX2-34 "INJECTOR 6" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoNET_FAMILYOEM-4-T ↔ MAXXECUGEN2R-MX3-29OEM-4-T "EVAP purge solenoid" [low_side_out] is wired to MAXXECUGEN2R-MX3-29 "INJECTOR 7" [injector_out]. Injector drivers can usually run general low-side loads; check current and PWM frequency.
infoUNMAPPEDOEM1 optional OEM pins are not mapped: OEM-4-L Tachometer output

Accepted (1)

CodeSubjectReasonBy
REQUIRED_UNMAPPEDOEM-4-IBattery-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-4 F: CAS SGT (cam trigger): no free cam_hall/cam_vr/frequency_in input on MaxxECU MaxxECU GEN2 RACE Not wired: - OEM-4 I: Permanent +12V (battery): MaxxECU MaxxECU GEN2 RACE has no battery-constant input; not needed - OEM-4 L: Tachometer output: no free tacho/frequency_out/low_side/ls_hs on MaxxECU MaxxECU GEN2 RACE - MAXXECUGEN2R-MX2 24: 12V supply 3: not fed (the stock ECU has no ignition-sense pin); feed it from a switched-ignition source

Sources

ReliabilityKindTitleURLArchiveCapturedSHA-256
4vendor_docAEM EMS 30-1720 Plug-and-Play adapter manual (1996-97 Miata)https://static.summitracing.com/global/images/instructions/avm-30-1720.pdf———
4vendor_docMaxxECU GEN2 pinout (RACE MX1–MX4 / TRACK MX1–MX3)http://www.maxxecu.com/webhelp/wirings-maxxecu_gen2_pinout.htmlarchive2026-10-05f689b8b6b08f
3community_copyMellens.net: 1996 Mazda Miata wiring diagrams (FSM-derived)http://www.mellens.net/mazda/mazda_miata_extra_manual/1996_wiring.pdf———