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.
100%
Stock ECU being replaced
NEXUSS3-A-1 Injector 1
NEXUSS3-A-26 ECR output
NEXUSS3-A-9 DPO 1
NEXUSS3-A-2 Injector 2
NEXUSS3-A-6 Injector 6
NEXUSS3-A-7 Injector 7
NEXUSS3-A-3 Injector 3
NEXUSS3-A-8 Injector 8
NEXUSS3-A-19 HBO 1
NEXUSS3-A-4 Injector 4
NEXUSS3-A-12 DPO 2
L no data
NEXUSS3-A-14 DPO 3
NEXUSS3-A-20 HBO 2
NEXUSS3-A-16 DPO 5
ISC valve +14V feed
NEXUSS3-A-5 Injector 5
NEXUSS3-A-21 HBO 3
OEM-2
Stock ECU being replaced
AInjector 1
BCooling fan relay
CCondenser fan relay
DInjector 2
EEGR valve
FEGR valve
GInjector 3
HEGR valve
IEGR valve
JInjector 4
KA/C clutch relay
L no data
MFuel pump relay
NVTCS solenoid (intake butterflies)
OFuel pump relay (non-immobiliser)
PISC valve +14V feed
QISC valve low side
RMalfunction indicator lamp (MIL)
GND
GND
NEXUSS3-A-22 HBO 4
E no data
NEXUSS3-A-27 Ignition 1
G no data
NEXUSS3-A-15 DPO 4
NEXUSS3-A-28 Ignition 2
NEXUSS3-C-33 WBI 1 Heater -
L no data
N no data
NEXUSS3-A-17 DPO 6
R no data
NEXUSS3-C-6 SPI 2
NEXUSS3-C-5 SPI 1
NEXUSS3-C-3 Home +
W–X no data
NEXUSS3-C-1 Trigger +
Z no data
OEM-3
Stock ECU being replaced
APower ground
BPower ground
CPurge solenoid valve
E no data
FIgnition 1 (coils 1+4, wasted spark)
G no data
HMain relay
IIgnition 2 (coils 2+3, wasted spark)
JFront O2 heater
L no data
N no data
PRear O2 heater
R no data
SImmobiliser
TVehicle speed
VCam position (CMP)
W–X no data
YCrank position (CKP)
Z no data
GND
NEXUSS3-C-7 SPI 3
NEXUSS3-C-8 SPI 4
VVT oil-control solenoid +12V feed
NEXUSS3-C-19 SPI 5
G no data
NEXUSS3-C-20 SPI 6
NEXUSS3-C-18 AVI 9
NEXUSS3-C-27 AVI 10
K no data
5V ref
NEXUSS3-C-23 Knock 1
NEXUSS3-C-16 AVI 7
0V sensor
NEXUSS3-C-15 AVI 6
Q no data
NEXUSS3-A-13 Ignition switch input
U no data
NEXUSS3-C-12 AVI 3
NEXUSS3-C-14 AVI 5
NEXUSS3-C-10 AVI 1
Y no data
NEXUSS3-C-13 AVI 4
AB no data
NEXUSS3-C-17 AVI 8
NEXUSS3-C-11 AVI 2
ECU power +14V (main relay)
OEM-4
Stock ECU being replaced
APower ground
BBrake switch
CPower steering pressure switch
DVVT oil-control solenoid +12V feed
FA/C request
G no data
HNeutral switch
IClutch switch
JVTCS vacuum switch
K no data
L+5V sensor supply
MKnock sensor
NIntake air temperature (IAT)
OSignal ground
PCoolant temperature (ECT)
Q no data
SIgnition switch (IG1) sense
U no data
VThrottle position (TPS)
WFront O2 signal
XMass air flow (MAF)
Y no data
AARear O2 signal
AB no data
ADFuel level
AEPressure sensor (Mazda: EGR boost sensor)
AFECU power +14V (main relay)
NEXUSS3
NEXUSS3-A
NEXUSS3
1Injector 1
2Injector 2
3Injector 3
4Injector 4
5Injector 5
6Injector 6
7Injector 7
8Injector 8
9DPO 1
10Battery ground
11Battery ground
12DPO 2
13Ignition switch input
14DPO 3
15DPO 4
16DPO 5
17DPO 6
18+12V switched input
19HBO 1
20HBO 2
21HBO 3
22HBO 4
25+12V switched input
26ECR output
27Ignition 1
28Ignition 2
OEM-2-A Injector 1
OEM-2-D Injector 2
OEM-2-G Injector 3
OEM-2-J Injector 4
OEM-2-Q ISC valve low side
OEM-2-E EGR valve
OEM-2-F EGR valve
OEM-2-H EGR valve
OEM-2-C Condenser fan relay
GND
GND
OEM-2-K A/C clutch relay
OEM-4-S Ignition switch (IG1) sense
OEM-2-M Fuel pump relay
OEM-3-H Main relay
OEM-2-O Fuel pump relay (non-immobiliser)
OEM-3-P Rear O2 heater
+12V switched input
OEM-2-I EGR valve
OEM-2-N VTCS solenoid (intake butterflies)
OEM-2-R Malfunction indicator lamp (MIL)
OEM-3-C Purge solenoid valve
+12V switched input
OEM-2-B Cooling fan relay
OEM-3-F Ignition 1 (coils 1+4, wasted spark)
OEM-3-I Ignition 2 (coils 2+3, wasted spark)
NEXUSS3-C
NEXUSS3
1Trigger +
2Trigger -
3Home +
4Home -
5SPI 1
6SPI 2
7SPI 3
8SPI 4
10AVI 1
11AVI 2
12AVI 3
13AVI 4
14AVI 5
15AVI 6
16AVI 7
17AVI 8
18AVI 9
19SPI 5
20SPI 6
23Knock 1
25+5V
26Signal ground
27AVI 10
33WBI 1 Heater -
OEM-3-Y Crank position (CKP)
OEM-4-O Signal ground (via SP-0V)
OEM-3-V Cam position (CMP)
OEM-4-O Signal ground (via SP-0V)
OEM-3-T Vehicle speed
OEM-3-S Immobiliser
OEM-4-B Brake switch
OEM-4-C Power steering pressure switch
OEM-4-X Mass air flow (MAF)
OEM-4-AE Pressure sensor (Mazda: EGR boost sensor)
OEM-4-V Throttle position (TPS)
OEM-4-AA Rear O2 signal
OEM-4-W Front O2 signal
OEM-4-P Coolant temperature (ECT)
OEM-4-N Intake air temperature (IAT)
OEM-4-AD Fuel level
OEM-4-I Clutch switch
OEM-4-F A/C request
OEM-4-H Neutral switch
OEM-4-M Knock sensor
5V ref
0V sensor
OEM-4-J VTCS vacuum switch
OEM-3-J Front O2 heater
SP-GND · 6 pins
SP-14V · 6 pins
SP-0V · 5 pins
Press enter or space to select a node. You can then use the arrow keys to move the node around. Press delete to remove it and escape to cancel.
Press enter or space to select an edge. You can then press delete to remove it or escape to cancel.