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VW Corrado VR6 12v (AAA) Motronic M2.9 OBD1 → DTAFast T12 (auto)

VW Corrado VR6 12v (AAA) Motronic M2.9 OBD1 — DTAFast — T12
⚠ 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 errors2: read the Findings page before cutting any wire
Size of the job46 wires · 7 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-A-23SP-14V-10.85☐☐☐☐☐☐☐
W2SP-14V-1T12-C1-310.85☐☐☐☐☐☐☐
W3OEM-A-54T12-C3-260.85☐☐☐☐☐☐☐
W4OEM-A-1SP-GND-10.85☐☐☐☐☐☐☐
W5OEM-A-10SP-GND-10.85☐☐☐☐☐☐☐
W6OEM-A-55SP-GND-10.85☐☐☐☐☐☐☐
W7OEM-A-56SP-GND-10.85☐☐☐☐☐☐☐
W8OEM-A-7SP-GND-10.85☐☐☐☐☐☐☐
W9SP-GND-1T12-C1-130.85☐☐☐☐☐☐☐
W10SP-GND-1T12-C1-140.85☐☐☐☐☐☐☐
W11OEM-A-16SP-0V-10.5☐☐☐☐☐☐☐
W12OEM-A-33SP-0V-10.5☐☐☐☐☐☐☐
W13OEM-A-67SP-0V-10.5☐☐☐☐☐☐☐
W14SP-0V-1T12-C2-210.5☐☐☐☐☐☐☐
W15SP-0V-1T12-C2-330.5☐☐☐☐☐☐☐
W16OEM-A-41T12-C2-240.5☐☐☐☐☐☐☐
W17OEM-A-68T12-C2-120.5☐☐☐☐☐☐☐
W18OEM-A-44T12-C2-220.5☐☐☐☐☐☐☐
W19OEM-A-34T12-C3-310.5☐☐☐☐☐☐☐
W20OEM-A-8T12-C1-100.5☐☐☐☐☐☐☐
W21OEM-A-60T12-C1-180.5☐☐☐☐☐☐☐
W22OEM-A-52T12-C1-10.5☐☐☐☐☐☐☐
W23OEM-A-24T12-C1-90.5☐☐☐☐☐☐☐
W24OEM-A-3T12-C1-170.5☐☐☐☐☐☐☐
W25OEM-A-26T12-C1-340.5☐☐☐☐☐☐☐
W26OEM-A-4T12-C1-250.5☐☐☐☐☐☐☐
W27OEM-A-25T12-C1-160.5☐☐☐☐☐☐☐
W28OEM-A-2T12-C1-150.5☐☐☐☐☐☐☐
W29OEM-A-17T12-C2-100.5☐☐☐☐☐☐☐
W30OEM-A-40T12-C2-10.5☐☐☐☐☐☐☐
W31OEM-A-14T12-C2-70.5☐☐☐☐☐☐☐
W32OEM-A-49T12-C1-50.5☐☐☐☐☐☐☐
W33OEM-A-6T12-C1-40.5☐☐☐☐☐☐☐
W34OEM-A-9T12-C1-30.5☐☐☐☐☐☐☐
W35OEM-A-27T12-C3-220.5☐☐☐☐☐☐☐
W36OEM-A-31T12-C3-230.5☐☐☐☐☐☐☐
W37OEM-A-5T12-C3-240.5☐☐☐☐☐☐☐
W38OEM-A-53T12-C3-250.5☐☐☐☐☐☐☐
W39OEM-A-22T12-C3-100.5☐☐☐☐☐☐☐
W40OEM-A-51T12-C3-40.5☐☐☐☐☐☐☐
W41OEM-A-20T12-C2-50.5☐☐☐☐☐☐☐
W42OEM-A-15T12-C2-250.5☐☐☐☐☐☐☐
W43OEM-A-36T12-C2-170.5☐☐☐☐☐☐☐
W44OEM-A-65T12-C2-20.5☐☐☐☐☐☐☐
W45OEM-A-37T12-C2-40.5☐☐☐☐☐☐☐
W46OEM-A-39T12-C2-80.5☐☐☐☐☐☐☐

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
1T12-C1-13T12-C1-31open (OL)power ground must not touch +12 V supply
2T12-C1-13T12-C2-24open (OL)power ground must not touch 5 V sensor reference
3T12-C1-13T12-C3-26open (OL)power ground must not touch +12 V supply
4T12-C1-31T12-C2-24open (OL)+12 V supply must not touch 5 V sensor reference
5T12-C2-21T12-C1-31open (OL)sensor ground must not touch +12 V supply
6T12-C2-21T12-C2-24open (OL)sensor ground must not touch 5 V sensor reference
7T12-C2-21T12-C3-26open (OL)sensor ground must not touch +12 V supply
8T12-C2-24T12-C3-26open (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

OEM-ASP-0VSP-14VSP-GNDT12-C1T12-C2T12-C3

Connectors

OEM-A

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Ground (E-1)—W4—0.85SP-GND-1———
10Ground (OBD1 EGR enable)—W5—0.85SP-GND-1———
14Coolant temperature (CLT)—W31—0.5T12-C2-7———
15EGR temperature sensor—W42—0.5T12-C2-25———
16MAF ground—W11—0.5SP-0V-1———
17MAF signal—W29—0.5T12-C2-10———
2Injector 6 (cyl 6)—W28—0.5T12-C1-15———
20O2 sensor 1 (primary)—W41—0.5T12-C2-5———
21Diagnostic L-line————————
22Tachometer output—W39—0.5T12-C3-10———
23ECU main power (from engine-electronics relay)—W1—0.85SP-14V-1———
24Injector 1 (cyl 1)—W23—0.5T12-C1-9———
25Injector 5 (cyl 5)—W27—0.5T12-C1-16———
26Injector 3 (cyl 3)—W25—0.5T12-C1-34———
27Idle air control valve—W35—0.5T12-C3-22———
3Injector 2 (cyl 2)—W24—0.5T12-C1-17———
31EVAP canister purge valve—W36—0.5T12-C3-23———
33Sensor ground bus—W12—0.5SP-0V-1———
34Knock sensor 1—W19—0.5T12-C3-31———
36Intake air temperature (IAT)—W43—0.5T12-C2-17———
37A/C compressor switch—W45—0.5T12-C2-4———
38Ignition switch (run/start)————————
39A/C switch (cabin)—W46—0.5T12-C2-8———
4Injector 4 (cyl 4)—W26—0.5T12-C1-25———
40Throttle position sensor 1—W30—0.5T12-C2-1———
41TPS power (+5V)—W16—0.5T12-C2-24———
43Diagnostic K-line————————
44Camshaft position sensor (G40)—W18—0.5T12-C2-22———
49Secondary air injection relay control—W32—0.5T12-C1-5———
5Check engine light (MIL)—W37—0.5T12-C3-24———
51MFA fuel-consumption signal—W40—0.5T12-C3-4———
52Ignition coil 4 (coil pack pin 4)—W22—0.5T12-C1-1———
53Idle air control valve (2nd)—W38—0.5T12-C3-25———
54Battery constant (+12V)—W3—0.85T12-C3-26———
55Ground (E-3)—W6—0.85SP-GND-1———
56Ground (E-4)—W7—0.85SP-GND-1———
59Mass airflow sensor (5th terminal)————————
6Fuel pump relay control—W33—0.5T12-C1-4———
60Ignition coil 3 (coil pack pin 3)—W21—0.5T12-C1-18———
65Vehicle speed sensor (VSS)—W44—0.5T12-C2-2———
67Crank sensor return (VR-)—W13—0.5SP-0V-1———
68Crank position sensor (G28, VR+)—W17—0.5T12-C2-12———
7Ground (E-2)—W8—0.85SP-GND-1———
8Ignition coil 2 (coil pack pin 2)—W20—0.5T12-C1-10———
9Engine electronics relay control—W34—0.5T12-C1-3———

SP-0V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W11—0.5OEM-A-16———
1——W12—0.5OEM-A-33———
1——W13—0.5OEM-A-67———
1——W14—0.5T12-C2-21———
1——W15—0.5T12-C2-33———

SP-14V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W1—0.85OEM-A-23———
1——W2—0.85T12-C1-31———

SP-GND

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W4—0.85OEM-A-1———
1——W5—0.85OEM-A-10———
1——W6—0.85OEM-A-55———
1——W7—0.85OEM-A-56———
1——W8—0.85OEM-A-7———
1——W9—0.85T12-C1-13———
1——W10—0.85T12-C1-14———

T12-C1

Mating face
T12-C1-1 · Coil 31T12-C1-2 · Coil 112T12-C1-3 · PWM 33T12-C1-4 · PWM 24T12-C1-5 · PWM 15T12-C1-6 · Motor 1 +6T12-C1-7 · Motor 1 -7T12-C1-8 · Injector 118T12-C1-9 · Injector 19T12-C1-10 · Coil 110T12-C1-11 · Coil 511T12-C1-12 · Coil 712T12-C1-13 · Power Ground 113T12-C1-14 · Power Ground 214T12-C1-15 · Injector 615T12-C1-16 · Injector 516T12-C1-17 · Injector 217T12-C1-18 · Coil 218T12-C1-19 · Coil 819T12-C1-20 · Coil 920T12-C1-21 · Injector 921T12-C1-22 · Injector 1022T12-C1-23 · Injector 823T12-C1-24 · Injector 724T12-C1-25 · Injector 425T12-C1-26 · Coil 426T12-C1-27 · Coil 627T12-C1-28 · Coil 1028T12-C1-29 · Motor 2 +29T12-C1-30 · Motor 2 -30T12-C1-31 · Ignition 12v In31T12-C1-32 · Injector 1232T12-C1-33 · Coil 1233T12-C1-34 · Injector 334
Wire side
T12-C1-1 · Coil 31T12-C1-2 · Coil 112T12-C1-3 · PWM 33T12-C1-4 · PWM 24T12-C1-5 · PWM 15T12-C1-6 · Motor 1 +6T12-C1-7 · Motor 1 -7T12-C1-8 · Injector 118T12-C1-9 · Injector 19T12-C1-10 · Coil 110T12-C1-11 · Coil 511T12-C1-12 · Coil 712T12-C1-13 · Power Ground 113T12-C1-14 · Power Ground 214T12-C1-15 · Injector 615T12-C1-16 · Injector 516T12-C1-17 · Injector 217T12-C1-18 · Coil 218T12-C1-19 · Coil 819T12-C1-20 · Coil 920T12-C1-21 · Injector 921T12-C1-22 · Injector 1022T12-C1-23 · Injector 823T12-C1-24 · Injector 724T12-C1-25 · Injector 425T12-C1-26 · Coil 426T12-C1-27 · Coil 627T12-C1-28 · Coil 1028T12-C1-29 · Motor 2 +29T12-C1-30 · Motor 2 -30T12-C1-31 · Ignition 12v In31T12-C1-32 · Injector 1232T12-C1-33 · Coil 1233T12-C1-34 · Injector 334
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Coil 3—W22—0.5OEM-A-52———
2Coil 11————————
3PWM 3—W34—0.5OEM-A-9———
4PWM 2—W33—0.5OEM-A-6———
5PWM 1—W32—0.5OEM-A-49———
6Motor 1 +————————
7Motor 1 -————————
8Injector 11————————
9Injector 1—W23—0.5OEM-A-24———
10Coil 1—W20—0.5OEM-A-8———
11Coil 5————————
12Coil 7————————
13Power Ground 1—W9—0.85SP-GND-1———
14Power Ground 2—W10—0.85SP-GND-1———
15Injector 6—W28—0.5OEM-A-2———
16Injector 5—W27—0.5OEM-A-25———
17Injector 2—W24—0.5OEM-A-3———
18Coil 2—W21—0.5OEM-A-60———
19Coil 8————————
20Coil 9————————
21Injector 9————————
22Injector 10————————
23Injector 8————————
24Injector 7————————
25Injector 4—W26—0.5OEM-A-4———
26Coil 4————————
27Coil 6————————
28Coil 10————————
29Motor 2 +————————
30Motor 2 -————————
31Ignition 12v In—W2—0.85SP-14V-1———
32Injector 12————————
33Coil 12————————
34Injector 3—W25—0.5OEM-A-26———

T12-C2

Mating face
T12-C2-1 · Analogue 21T12-C2-2 · Wheel 12T12-C2-3 · Analogue 103T12-C2-4 · Digital 14T12-C2-5 · Analogue 35T12-C2-6 · Analogue 46T12-C2-7 · Thermistor 17T12-C2-8 · Digital 28T12-C2-9 · 5v Output9T12-C2-10 · Analogue 110T12-C2-11 · Digital 311T12-C2-12 · Crank12T12-C2-13 · Analogue 1213T12-C2-14 · Digital 414T12-C2-15 · Digital 515T12-C2-16 · Analogue 1116T12-C2-17 · Thermistor 317T12-C2-18 · Analogue 518T12-C2-19 · Analogue 619T12-C2-20 · Wheel 220T12-C2-21 · Sensor Ground21T12-C2-22 · Cam 122T12-C2-23 · Cam 323T12-C2-24 · 5v Output24T12-C2-25 · Thermistor 225T12-C2-26 · CAN High26T12-C2-27 · Digital 627T12-C2-28 · CAN Low28T12-C2-29 · Cam 229T12-C2-30 · Cam 430T12-C2-31 · Wheel 331T12-C2-32 · Wheel 432T12-C2-33 · Sensor Ground33T12-C2-34 · Analogue 934
Wire side
T12-C2-1 · Analogue 21T12-C2-2 · Wheel 12T12-C2-3 · Analogue 103T12-C2-4 · Digital 14T12-C2-5 · Analogue 35T12-C2-6 · Analogue 46T12-C2-7 · Thermistor 17T12-C2-8 · Digital 28T12-C2-9 · 5v Output9T12-C2-10 · Analogue 110T12-C2-11 · Digital 311T12-C2-12 · Crank12T12-C2-13 · Analogue 1213T12-C2-14 · Digital 414T12-C2-15 · Digital 515T12-C2-16 · Analogue 1116T12-C2-17 · Thermistor 317T12-C2-18 · Analogue 518T12-C2-19 · Analogue 619T12-C2-20 · Wheel 220T12-C2-21 · Sensor Ground21T12-C2-22 · Cam 122T12-C2-23 · Cam 323T12-C2-24 · 5v Output24T12-C2-25 · Thermistor 225T12-C2-26 · CAN High26T12-C2-27 · Digital 627T12-C2-28 · CAN Low28T12-C2-29 · Cam 229T12-C2-30 · Cam 430T12-C2-31 · Wheel 331T12-C2-32 · Wheel 432T12-C2-33 · Sensor Ground33T12-C2-34 · Analogue 934
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Analogue 2—W30—0.5OEM-A-40———
2Wheel 1—W44—0.5OEM-A-65———
3Analogue 10————————
4Digital 1—W45—0.5OEM-A-37———
5Analogue 3—W41—0.5OEM-A-20———
6Analogue 4————————
7Thermistor 1—W31—0.5OEM-A-14———
8Digital 2—W46—0.5OEM-A-39———
95v Output————————
10Analogue 1—W29—0.5OEM-A-17———
11Digital 3————————
12Crank—W17—0.5OEM-A-68———
13Analogue 12————————
14Digital 4————————
15Digital 5————————
16Analogue 11————————
17Thermistor 3—W43—0.5OEM-A-36———
18Analogue 5————————
19Analogue 6————————
20Wheel 2————————
21Sensor Ground—W14—0.5SP-0V-1———
22Cam 1—W18—0.5OEM-A-44———
23Cam 3————————
245v Output—W16—0.5OEM-A-41———
25Thermistor 2—W42—0.5OEM-A-15———
26CAN High————————
27Digital 6————————
28CAN Low————————
29Cam 2————————
30Cam 4————————
31Wheel 3————————
32Wheel 4————————
33Sensor Ground—W15—0.5SP-0V-1———
34Analogue 9————————

T12-C3

Mating face
T12-C3-1 · Lambda 2 Pump Current1T12-C3-2 · Lambda 2 VGND2T12-C3-3 · Lambda 2 Heater Negative3T12-C3-4 · PWM 94T12-C3-5 · Lambda 2 Trim Resistor5T12-C3-6 · Lambda 2 Nernst Voltage6T12-C3-7 · Lambda 1 Pump Current7T12-C3-8 · Lambda 1 VGND8T12-C3-9 · Lambda 1 Heater Negative9T12-C3-10 · PWM 810T12-C3-11 · Lambda 1 Trim Resistor11T12-C3-12 · Lambda 1 Nernst Voltage12T12-C3-13 · Analogue 1313T12-C3-14 · Analogue 1414T12-C3-15 · Analogue 1515T12-C3-16 · Analogue 1616T12-C3-17 · Analogue 717T12-C3-18 · Analogue 818T12-C3-19 · Digital 719T12-C3-20 · Digital 820T12-C3-21 · Digital 921T12-C3-22 · PWM 422T12-C3-23 · PWM 523T12-C3-24 · PWM 624T12-C3-25 · PWM 725T12-C3-26 · Permanent 12v26T12-C3-27 · Permanent 12v27T12-C3-28 · PWM 1028T12-C3-29 · PWM 1129T12-C3-30 · PWM 1230T12-C3-31 · Knock 131T12-C3-32 · Knock 232T12-C3-33 · CAN 2 High33T12-C3-34 · CAN 2 Low34
Wire side
T12-C3-1 · Lambda 2 Pump Current1T12-C3-2 · Lambda 2 VGND2T12-C3-3 · Lambda 2 Heater Negative3T12-C3-4 · PWM 94T12-C3-5 · Lambda 2 Trim Resistor5T12-C3-6 · Lambda 2 Nernst Voltage6T12-C3-7 · Lambda 1 Pump Current7T12-C3-8 · Lambda 1 VGND8T12-C3-9 · Lambda 1 Heater Negative9T12-C3-10 · PWM 810T12-C3-11 · Lambda 1 Trim Resistor11T12-C3-12 · Lambda 1 Nernst Voltage12T12-C3-13 · Analogue 1313T12-C3-14 · Analogue 1414T12-C3-15 · Analogue 1515T12-C3-16 · Analogue 1616T12-C3-17 · Analogue 717T12-C3-18 · Analogue 818T12-C3-19 · Digital 719T12-C3-20 · Digital 820T12-C3-21 · Digital 921T12-C3-22 · PWM 422T12-C3-23 · PWM 523T12-C3-24 · PWM 624T12-C3-25 · PWM 725T12-C3-26 · Permanent 12v26T12-C3-27 · Permanent 12v27T12-C3-28 · PWM 1028T12-C3-29 · PWM 1129T12-C3-30 · PWM 1230T12-C3-31 · Knock 131T12-C3-32 · Knock 232T12-C3-33 · CAN 2 High33T12-C3-34 · CAN 2 Low34
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Lambda 2 Pump Current————————
2Lambda 2 VGND————————
3Lambda 2 Heater Negative————————
4PWM 9—W40—0.5OEM-A-51———
5Lambda 2 Trim Resistor————————
6Lambda 2 Nernst Voltage————————
7Lambda 1 Pump Current————————
8Lambda 1 VGND————————
9Lambda 1 Heater Negative————————
10PWM 8—W39—0.5OEM-A-22———
11Lambda 1 Trim Resistor————————
12Lambda 1 Nernst Voltage————————
13Analogue 13————————
14Analogue 14————————
15Analogue 15————————
16Analogue 16————————
17Analogue 7————————
18Analogue 8————————
19Digital 7————————
20Digital 8————————
21Digital 9————————
22PWM 4—W35—0.5OEM-A-27———
23PWM 5—W36—0.5OEM-A-31———
24PWM 6—W37—0.5OEM-A-5———
25PWM 7—W38—0.5OEM-A-53———
26Permanent 12v—W3—0.85OEM-A-54———
27Permanent 12v————————
28PWM 10————————
29PWM 11————————
30PWM 12————————
31Knock 1—W19—0.5OEM-A-34———
32Knock 2————————
33CAN 2 High————————
34CAN 2 Low————————

Pin map

OEM pointOEM functionOEM familyTarget pointTarget functionTarget familyWire colourEvidence
OEM-A-1Ground (E-1)groundT12-C1-13 + T12-C1-14Power Ground 1 + Power Ground 2groundsingle_source
OEM-A-10Ground (OBD1 EGR enable)groundT12-C1-13 + T12-C1-14Power Ground 1 + Power Ground 2groundsingle_source
OEM-A-14Coolant temperature (CLT)temp_inT12-C2-7Thermistor 1temp_insingle_source
OEM-A-15EGR temperature sensortemp_inT12-C2-25Thermistor 2temp_insingle_source
OEM-A-16MAF groundsensor_groundT12-C2-21 + T12-C2-33Sensor Ground + Sensor Groundsensor_groundsingle_source
OEM-A-17MAF signalanalog_inT12-C2-10Analogue 1analog_insingle_source
OEM-A-2Injector 6 (cyl 6)injector_outT12-C1-15Injector 6injector_outsingle_source
OEM-A-20O2 sensor 1 (primary)lambda_nb_inT12-C2-5Analogue 3analog_insingle_source
OEM-A-21Diagnostic L-lineserial———single_source
OEM-A-22Tachometer outputtacho_outT12-C3-10PWM 8low_side_outsingle_source
OEM-A-23ECU main power (from engine-electronics relay)power_inT12-C1-31Ignition 12v Inpower_insingle_source
OEM-A-24Injector 1 (cyl 1)injector_outT12-C1-9Injector 1injector_outsingle_source
OEM-A-25Injector 5 (cyl 5)injector_outT12-C1-16Injector 5injector_outsingle_source
OEM-A-26Injector 3 (cyl 3)injector_outT12-C1-34Injector 3injector_outsingle_source
OEM-A-27Idle air control valvelow_side_outT12-C3-22PWM 4low_side_outsingle_source
OEM-A-3Injector 2 (cyl 2)injector_outT12-C1-17Injector 2injector_outsingle_source
OEM-A-31EVAP canister purge valvelow_side_outT12-C3-23PWM 5low_side_outsingle_source
OEM-A-33Sensor ground bussensor_groundT12-C2-21 + T12-C2-33Sensor Ground + Sensor Groundsensor_groundsingle_source
OEM-A-34Knock sensor 1knock_inT12-C3-31Knock 1knock_insingle_source
OEM-A-36Intake air temperature (IAT)temp_inT12-C2-17Thermistor 3temp_insingle_source
OEM-A-37A/C compressor switchdigital_inT12-C2-4Digital 1digital_insingle_source
OEM-A-38Ignition switch (run/start)digital_in———single_source
OEM-A-39A/C switch (cabin)digital_inT12-C2-8Digital 2digital_insingle_source
OEM-A-4Injector 4 (cyl 4)injector_outT12-C1-25Injector 4injector_outsingle_source
OEM-A-40Throttle position sensor 1analog_inT12-C2-1Analogue 2analog_insingle_source
OEM-A-41TPS power (+5V)vrefT12-C2-245v Outputvrefsingle_source
OEM-A-43Diagnostic K-lineserial———single_source
OEM-A-44Camshaft position sensor (G40)trigger_inT12-C2-22Cam 1trigger_insingle_source
OEM-A-49Secondary air injection relay controllow_side_outT12-C1-5PWM 1low_side_outsingle_source
OEM-A-5Check engine light (MIL)low_side_outT12-C3-24PWM 6low_side_outsingle_source
OEM-A-51MFA fuel-consumption signaltacho_outT12-C3-4PWM 9low_side_outsingle_source
OEM-A-52Ignition coil 4 (coil pack pin 4)ignition_outT12-C1-1Coil 3ignition_outsingle_source
OEM-A-53Idle air control valve (2nd)low_side_outT12-C3-25PWM 7low_side_outsingle_source
OEM-A-54Battery constant (+12V)power_inT12-C3-26Permanent 12vpower_insingle_source
OEM-A-55Ground (E-3)groundT12-C1-13 + T12-C1-14Power Ground 1 + Power Ground 2groundsingle_source
OEM-A-56Ground (E-4)groundT12-C1-13 + T12-C1-14Power Ground 1 + Power Ground 2groundsingle_source
OEM-A-59Mass airflow sensor (5th terminal)sensor_out———single_source
OEM-A-6Fuel pump relay controllow_side_outT12-C1-4PWM 2low_side_outsingle_source
OEM-A-60Ignition coil 3 (coil pack pin 3)ignition_outT12-C1-18Coil 2ignition_outsingle_source
OEM-A-65Vehicle speed sensor (VSS)digital_inT12-C2-2Wheel 1digital_insingle_source
OEM-A-67Crank sensor return (VR-)sensor_groundT12-C2-21 + T12-C2-33Sensor Ground + Sensor Groundsensor_groundsingle_source
OEM-A-68Crank position sensor (G28, VR+)trigger_inT12-C2-12Cranktrigger_insingle_source
OEM-A-7Ground (E-2)groundT12-C1-13 + T12-C1-14Power Ground 1 + Power Ground 2groundsingle_source
OEM-A-8Ignition coil 2 (coil pack pin 2)ignition_outT12-C1-10Coil 1ignition_outsingle_source
OEM-A-9Engine electronics relay controllow_side_outT12-C1-3PWM 3low_side_outsingle_source

Cut list

WireFromToGauge (mm²)ColourLengthSignalIdent
W1OEM-A-23SP-14V-10.85no routeECU main power (from engine-electronics relay)—
W2SP-14V-1T12-C1-310.85no routeIgnition 12v In—
W3OEM-A-54T12-C3-260.85no routeBattery constant (+12V)—
W4OEM-A-1SP-GND-10.85no routeGround (E-1)—
W5OEM-A-10SP-GND-10.85no routeGround (OBD1 EGR enable)—
W6OEM-A-55SP-GND-10.85no routeGround (E-3)—
W7OEM-A-56SP-GND-10.85no routeGround (E-4)—
W8OEM-A-7SP-GND-10.85no routeGround (E-2)—
W9SP-GND-1T12-C1-130.85no routePower Ground 1—
W10SP-GND-1T12-C1-140.85no routePower Ground 2—
W11OEM-A-16SP-0V-10.5no routeMAF ground—
W12OEM-A-33SP-0V-10.5no routeSensor ground bus—
W13OEM-A-67SP-0V-10.5no routeCrank sensor return (VR-)—
W14SP-0V-1T12-C2-210.5no routeSensor Ground—
W15SP-0V-1T12-C2-330.5no routeSensor Ground—
W16OEM-A-41T12-C2-240.5no routeTPS power (+5V)—
W17OEM-A-68T12-C2-120.5no routeCrank position sensor (G28, VR+)—
W18OEM-A-44T12-C2-220.5no routeCamshaft position sensor (G40)—
W19OEM-A-34T12-C3-310.5no routeKnock sensor 1—
W20OEM-A-8T12-C1-100.5no routeIgnition coil 2 (coil pack pin 2)—
W21OEM-A-60T12-C1-180.5no routeIgnition coil 3 (coil pack pin 3)—
W22OEM-A-52T12-C1-10.5no routeIgnition coil 4 (coil pack pin 4)—
W23OEM-A-24T12-C1-90.5no routeInjector 1 (cyl 1)—
W24OEM-A-3T12-C1-170.5no routeInjector 2 (cyl 2)—
W25OEM-A-26T12-C1-340.5no routeInjector 3 (cyl 3)—
W26OEM-A-4T12-C1-250.5no routeInjector 4 (cyl 4)—
W27OEM-A-25T12-C1-160.5no routeInjector 5 (cyl 5)—
W28OEM-A-2T12-C1-150.5no routeInjector 6 (cyl 6)—
W29OEM-A-17T12-C2-100.5no routeMAF signal—
W30OEM-A-40T12-C2-10.5no routeThrottle position sensor 1—
W31OEM-A-14T12-C2-70.5no routeCoolant temperature (CLT)—
W32OEM-A-49T12-C1-50.5no routeSecondary air injection relay control—
W33OEM-A-6T12-C1-40.5no routeFuel pump relay control—
W34OEM-A-9T12-C1-30.5no routeEngine electronics relay control—
W35OEM-A-27T12-C3-220.5no routeIdle air control valve—
W36OEM-A-31T12-C3-230.5no routeEVAP canister purge valve—
W37OEM-A-5T12-C3-240.5no routeCheck engine light (MIL)—
W38OEM-A-53T12-C3-250.5no routeIdle air control valve (2nd)—
W39OEM-A-22T12-C3-100.5no routeTachometer output—
W40OEM-A-51T12-C3-40.5no routeMFA fuel-consumption signal—
W41OEM-A-20T12-C2-50.5no routeO2 sensor 1 (primary)—
W42OEM-A-15T12-C2-250.5no routeEGR temperature sensor—
W43OEM-A-36T12-C2-170.5no routeIntake air temperature (IAT)—
W44OEM-A-65T12-C2-20.5no routeVehicle speed sensor (VSS)—
W45OEM-A-37T12-C2-40.5no routeA/C compressor switch—
W46OEM-A-39T12-C2-80.5no routeA/C switch (cabin)—

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)37.000ea

ECU setup sheet

RoleEngine refEngine signalSensorECU pointECU functionECU classSetup flag
No configured channels.

Findings

Open (5)

SeverityCodeSubjectMessage
errorPHYS_REQUIRED_OPENT12-C3-27T12-C3-27 "Permanent 12v" is required but not wired.
errorREQUIRED_UNMAPPEDOEM-A-38Required OEM function "Ignition switch (run/start)" (digital_in) is not connected to the new ECU.
infoNET_FAMILYOEM-A-22 ↔ T12-C3-10OEM-A-22 "Tachometer output" [tacho_out] is wired to T12-C3-10 "PWM 8" [low_side_out]. Tacho as a low-side output: check the tach needs a pull-up.
infoNET_FAMILYOEM-A-51 ↔ T12-C3-4OEM-A-51 "MFA fuel-consumption signal" [tacho_out] is wired to T12-C3-4 "PWM 9" [low_side_out]. Tacho as a low-side output: check the tach needs a pull-up.
infoUNMAPPEDOEM3 optional OEM pins are not mapped: OEM-A-21 Diagnostic L-line; OEM-A-43 Diagnostic K-line; OEM-A-59 Mass airflow sensor (5th terminal)

Accepted (0)

CodeSubjectReasonBy

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 38: Ignition switch (run/start): key-on 12 V sense — optional in a swap (the main relay is energized from keyed 12 V, not from this pin); DTAFast T12 has no dedicated key-on input - T12-C3 27: Permanent 12v: required by DTAFast T12 but no stock pin feeds it; wire by hand Not wired: - OEM-A 21: Diagnostic L-line: no free k_line on DTAFast T12 - OEM-A 43: Diagnostic K-line: no free k_line on DTAFast T12 - OEM-A 59: Mass airflow sensor (5th terminal): no rule for class sensor_signal; wire by hand

Sources

ReliabilityKindTitleURLArchiveCapturedSHA-256
4vendor_docDTAFast T12+ ECU wiring diagram (served for T12 and T12+)https://cdn.shopify.com/s/files/1/0848/7508/4108/files/T12PLUS_Wiring-Diagram.pdf?v=1728572014———
2community_copya2resource: VR6/ABA Motronic M2.9 (OBD1) engine control unit pinouthttp://www.a2resource.com/electrical/management/motronicvr6aba.html———