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
GND
GND
KV8-D-15 Ignition switch input
KV8-A-10 Lambda 1 heater −
KV8-B-13 Aux 4
ECM power (J271 relay feed)
0V sensor
KV8-C-4 Analog in 3
0V sensor
KV8-C-6 Analog in 5
0V sensor
KV8-B-10 Aux 1
KV8-B-11 Aux 2
KV8-A-25 Lambda 1 pump cell (Ip)
KV8-A-22 Lambda 2 pump cell (Ip)
KV8-C-2 Analog in 1
KV8-C-27 Digital in 1
KV8-D-14 CAN 1 L
KV8-D-8 CAN 1 H
KV8-A-11 Lambda 2 heater −
KV8-B-12 Aux 3
KV8-D-9 EFI relay output (low side, 200 mA)
KV8-B-14 Aux 5
KV8-C-9 Analog in 8
KV8-C-10 Analog in 9
KV8-A-18 Lambda 1 Nernst cell (Vs)
KV8-A-21 Lambda 2 Nernst cell (Vs)
5V ref
5V ref
KV8-D-4 Crank index sensor +
5V ref
KV8-C-5 Analog in 4
KV8-C-11 Analog in 10
KV8-D-6 Sync sensor +
KV8-B-4 Injection 4
KV8-B-2 Injection 2
0V sensor
0V sensor
KV8-C-7 Analog in 6
KV8-C-8 Analog in 7
KV8-B-29 Ignition 4
KV8-B-27 Ignition 2
KV8-B-1 Injection 1
KV8-B-3 Injection 3
5V ref
5V ref
KV8-C-3 Analog in 2
KV8-B-26 Ignition 1
KV8-B-28 Ignition 3
KV8-B-15 Aux 6
KV8-B-16 Aux 7
KV8-D-11 Knock 1 +
KV8-D-17 Knock 2 +
0V sensor
KV8-B-17 Aux 8
KV8-B-18 Aux 9
KV8-B-19 Aux 10
ECM + coil power (J271 relay feed)
OEM-T121
Stock ECU being replaced
1ECU ground
2ECU ground
3Ignition switch +12V (term 15)
5Wideband lambda heater (Z19)
9Secondary-air injection valve (N112)
21ECM power (J271 relay feed)
29MAF sensor ground (G70)
33Accelerator pedal position 1 (G79)
34Accelerator pedal position 1 ground (G79)
35Accelerator pedal position 2 (G185)
36Accelerator pedal position 2 ground (G185)
47Check engine light (MIL)
48EPC warning light
51Wideband lambda pump (G39)
52Wideband lambda pump (G39)
53MAF sensor signal (G70)
54Road speed signal (VSS)
58CAN bus low
60CAN bus high
63Post-cat lambda heater (Z29)
64EVAP canister valve (N80)
65Fuel pump relay control
66Secondary-air pump relay (J299)
68Post-cat lambda signal (G130)
69Post-cat lambda signal (G130)
70Wideband lambda Nernst signal (G39)
71Wideband lambda Nernst signal (G39)
72Accelerator pedal position 1 5V supply (G79)
73Accelerator pedal position 2 5V supply (G185)
82Crank position sensor (G28)
83Throttle position sensor 5V supply (G187/G188)
84Throttle position sensor 1 (G187)
85Intake air temperature (G42)
86Camshaft position sensor (G40)
88Injector 4 (N33)
89Injector 2 (N31)
90Crank position sensor ground (G28)
91Throttle position sensor ground (G187/G188)
92Throttle position sensor 2 (G188)
93Engine coolant temperature (G62)
94Ignition coil 4 (N163)
95Ignition coil 2 (N128)
96Injector 1 (N30)
97Injector 3 (N32)
98Cam + boost sensor 5V supply (G40/G31)
99Knock sensor 5V supply (G61/G66)
101Boost pressure sensor (G31)
102Ignition coil 1 (N127)
103Ignition coil 3 (N158)
104Boost control solenoid (N75)
105Diverter valve (N249)
106Knock sensor 1 (G61)
107Knock sensor 2 (G66)
108Sensor ground
115VVT camshaft adjustment valve (N205)
117Throttle motor G186 (+)
118Throttle motor G186 (−)
121ECM + coil power (J271 relay feed)
KV8
KV8-A
KV8
10Lambda 1 heater −
11Lambda 2 heater −
18Lambda 1 Nernst cell (Vs)
21Lambda 2 Nernst cell (Vs)
22Lambda 2 pump cell (Ip)
25Lambda 1 pump cell (Ip)
OEM-T121-5 Wideband lambda heater (Z19)
OEM-T121-63 Post-cat lambda heater (Z29)
OEM-T121-70 Wideband lambda Nernst signal (G39)
OEM-T121-71 Wideband lambda Nernst signal (G39)
OEM-T121-52 Wideband lambda pump (G39)
OEM-T121-51 Wideband lambda pump (G39)
KV8-B
KV8
1Injection 1
2Injection 2
3Injection 3
4Injection 4
9ECU ground
10Aux 1
11Aux 2
12Aux 3
13Aux 4
14Aux 5
15Aux 6
16Aux 7
17Aux 8
18Aux 9
19Aux 10
26Ignition 1
27Ignition 2
28Ignition 3
29Ignition 4
34ECU ground
OEM-T121-96 Injector 1 (N30)
OEM-T121-89 Injector 2 (N31)
OEM-T121-97 Injector 3 (N32)
OEM-T121-88 Injector 4 (N33)
GND
OEM-T121-47 Check engine light (MIL)
OEM-T121-48 EPC warning light
OEM-T121-64 EVAP canister valve (N80)
OEM-T121-9 Secondary-air injection valve (N112)
OEM-T121-66 Secondary-air pump relay (J299)
OEM-T121-104 Boost control solenoid (N75)
OEM-T121-105 Diverter valve (N249)
OEM-T121-115 VVT camshaft adjustment valve (N205)
OEM-T121-117 Throttle motor G186 (+)
OEM-T121-118 Throttle motor G186 (−)
OEM-T121-102 Ignition coil 1 (N127)
OEM-T121-95 Ignition coil 2 (N128)
OEM-T121-103 Ignition coil 3 (N158)
OEM-T121-94 Ignition coil 4 (N163)
GND
KV8-C
KV8
1ECU ground
2Analog in 1
3Analog in 2
4Analog in 3
5Analog in 4
6Analog in 5
7Analog in 6
8Analog in 7
9Analog in 8
10Analog in 9
11Analog in 10
17Analog sensor 0V reference
25Analog sensor 0V reference
26ECU ground
27Digital in 1
GND
OEM-T121-53 MAF sensor signal (G70)
OEM-T121-101 Boost pressure sensor (G31)
OEM-T121-33 Accelerator pedal position 1 (G79)
OEM-T121-84 Throttle position sensor 1 (G187)
OEM-T121-35 Accelerator pedal position 2 (G185)
OEM-T121-92 Throttle position sensor 2 (G188)
OEM-T121-93 Engine coolant temperature (G62)
OEM-T121-68 Post-cat lambda signal (G130)
OEM-T121-69 Post-cat lambda signal (G130)
OEM-T121-85 Intake air temperature (G42)
0V sensor
0V sensor
GND
OEM-T121-54 Road speed signal (VSS)
KV8-D
KV8
1ECU 14V supply
2Aux 13–16 14V supply
4Crank index sensor +
5Crank index sensor −
6Sync sensor +
7Sync sensor −
8CAN 1 H
9EFI relay output (low side, 200 mA)
11Knock 1 +
14CAN 1 L
15Ignition switch input
17Knock 2 +
20Aux 9–12 14V supply
21Sensor supply Vref1 5.0V
22Sensor supply Vref2 5.0V
ECU 14V supply
Aux 13–16 14V supply
OEM-T121-82 Crank position sensor (G28)
SP-0V · 6 pins
OEM-T121-86 Camshaft position sensor (G40)
SP-0V · 6 pins
OEM-T121-60 CAN bus high
OEM-T121-65 Fuel pump relay control
OEM-T121-106 Knock sensor 1 (G61)
OEM-T121-58 CAN bus low
OEM-T121-3 Ignition switch +12V (term 15)
OEM-T121-107 Knock sensor 2 (G66)
Aux 9–12 14V supply
5V ref
5V ref
SP-GND · 7 pins
SP-0V · 11 pins
SP-5V1 · 5 pins
SP-5V2 · 4 pins
SP-14V · 6 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.