← Back

VW Golf/Jetta Mk2 1.8 8v Digifant II → DTAFast T8+ (auto)

VW Golf/Jetta Mk2 1.8 8v Digifant II — DTAFast — T8+
⚠ 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 errors3: read the Findings page before cutting any wire
Size of the job25 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-14SP-14V-10.85☐☐☐☐☐☐☐
W2SP-14V-1T8-C1-310.85☐☐☐☐☐☐☐
W3OEM-A-13SP-GND-10.85☐☐☐☐☐☐☐
W4OEM-A-19SP-GND-10.85☐☐☐☐☐☐☐
W5SP-GND-1T8-C1-130.85☐☐☐☐☐☐☐
W6SP-GND-1T8-C1-140.85☐☐☐☐☐☐☐
W7OEM-A-5SP-0V-10.5☐☐☐☐☐☐☐
W8OEM-A-6SP-0V-10.5☐☐☐☐☐☐☐
W9SP-0V-1T8-C2-210.5☐☐☐☐☐☐☐
W10SP-0V-1T8-C2-330.5☐☐☐☐☐☐☐
W11OEM-A-17T8-C2-240.5☐☐☐☐☐☐☐
W12OEM-A-18T8-C2-220.5☐☐☐☐☐☐☐
W13OEM-A-4T8-C3-310.5☐☐☐☐☐☐☐
W14OEM-A-25T8-C1-100.5☐☐☐☐☐☐☐
W15OEM-A-12T8-C1-90.5☐☐☐☐☐☐☐
W16OEM-A-3T8-C1-50.5☐☐☐☐☐☐☐
W17OEM-A-21T8-C2-100.5☐☐☐☐☐☐☐
W18OEM-A-10T8-C2-70.5☐☐☐☐☐☐☐
W19OEM-A-22T8-C1-40.5☐☐☐☐☐☐☐
W20OEM-A-23T8-C1-30.5☐☐☐☐☐☐☐
W21OEM-A-2T8-C2-10.5☐☐☐☐☐☐☐
W22OEM-A-9T8-C2-250.5☐☐☐☐☐☐☐
W23OEM-A-1T8-C2-40.5☐☐☐☐☐☐☐
W24OEM-A-11T8-C2-80.5☐☐☐☐☐☐☐
W25OEM-A-16T8-C2-110.5☐☐☐☐☐☐☐

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
1T8-C1-31T8-C2-21open (OL)+12 V supply must not touch sensor ground
2T8-C2-24T8-C2-21open (OL)5 V sensor reference must not touch sensor ground
3T8-C1-13T8-C1-31open (OL)power ground must not touch +12 V supply
4T8-C1-13T8-C2-24open (OL)power ground must not touch 5 V sensor reference
5T8-C1-31T8-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-ASP-0VSP-14VSP-GNDT8-C1T8-C2T8-C3

Connectors

OEM-A

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Starter signal (term 50)—W23—0.5T8-C2-4———
10Coolant temperature sensor—W18—0.5T8-C2-7———
11Idle/WOT throttle switch—W24—0.5T8-C2-8———
12Injector driver (batch, all 4)—W15—0.5T8-C1-9———
13Ground—W3—0.85SP-GND-1———
14ECU power (control-unit relay)—W1—0.85SP-14V-1———
16A/C compressor signal—W25—0.5T8-C2-11———
17AFM potentiometer supply—W11—0.5T8-C2-24———
18Hall sender signal (engine speed)—W12—0.5T8-C2-22———
19Ground—W4—0.85SP-GND-1———
2Oxygen (lambda) sensor signal—W21—0.5T8-C2-1———
21AFM signal—W17—0.5T8-C2-10———
22Idle stabilizer valve coil 1—W19—0.5T8-C1-4———
23Idle stabilizer valve coil 2—W20—0.5T8-C1-3———
25Ignition timing signal to TCI—W14—0.5T8-C1-10———
3Fuel pump relay control—W16—0.5T8-C1-5———
4Knock sensor signal—W13—0.5T8-C3-31———
5Knock sensor return—W7—0.5SP-0V-1———
6Sensor ground (CTS/Hall/AFM/throttle)—W8—0.5SP-0V-1———
7Knock sensor shield————————
8Hall sender supply (distributor)————————
9Intake air temperature sensor—W22—0.5T8-C2-25———

SP-0V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W7—0.5OEM-A-5———
1——W8—0.5OEM-A-6———
1——W9—0.5T8-C2-21———
1——W10—0.5T8-C2-33———

SP-14V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W1—0.85OEM-A-14———
1——W2—0.85T8-C1-31———

SP-GND

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W3—0.85OEM-A-13———
1——W4—0.85OEM-A-19———
1——W5—0.85T8-C1-13———
1——W6—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—W20—0.5OEM-A-23———
4PWM 2—W19—0.5OEM-A-22———
5PWM 1—W16—0.5OEM-A-3———
6Motor 1 +————————
7Motor 1 -————————
8—————————
9Injector 1—W15—0.5OEM-A-12———
10Coil 1—W14—0.5OEM-A-25———
11Coil 5————————
12Coil 7————————
13Power Ground 1—W5—0.85SP-GND-1———
14Power Ground 2—W6—0.85SP-GND-1———
15Injector 6————————
16Injector 5————————
17Injector 2————————
18Coil 2————————
19Coil 8————————
20—————————
21—————————
22—————————
23Injector 8————————
24Injector 7————————
25Injector 4————————
26Coil 4————————
27Coil 6————————
28—————————
29—————————
30—————————
31Ignition 12v In—W2—0.85SP-14V-1———
32—————————
33—————————
34Injector 3————————

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—W21—0.5OEM-A-2———
2Wheel 1————————
3Analogue 10————————
4Digital 1—W23—0.5OEM-A-1———
5Analogue 3————————
6Analogue 4————————
7Thermistor 1—W18—0.5OEM-A-10———
8Digital 2—W24—0.5OEM-A-11———
95v Output————————
10Analogue 1—W17—0.5OEM-A-21———
11Digital 3—W25—0.5OEM-A-16———
12Crank————————
13Analogue 12————————
14Digital 4————————
15Digital 5————————
16Analogue 11————————
17Thermistor 3————————
18Analogue 5————————
19Analogue 6————————
20Wheel 2————————
21Sensor Ground—W9—0.5SP-0V-1———
22Cam 1—W12—0.5OEM-A-18———
23—————————
245v Output—W11—0.5OEM-A-17———
25Thermistor 2—W22—0.5OEM-A-9———
26CAN High————————
27Digital 6————————
28CAN Low————————
29Cam 2————————
30—————————
31Wheel 3————————
32Wheel 4————————
33Sensor Ground—W10—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————————
4PWM 9————————
5Lambda 2 Trim Resistor————————
6Lambda 2 Nernst Voltage————————
7Lambda 1 Pump Current————————
8Lambda 1 VGND————————
9Lambda 1 Heater Negative————————
10PWM 8————————
11Lambda 1 Trim Resistor————————
12Lambda 1 Nernst Voltage————————
13—————————
14—————————
15—————————
16—————————
17Analogue 7————————
18Analogue 8————————
19—————————
20—————————
21—————————
22PWM 4————————
23PWM 5————————
24PWM 6————————
25PWM 7————————
26Permanent 12v————————
27Permanent 12v————————
28PWM 10————————
29—————————
30—————————
31Knock 1—W13—0.5OEM-A-4———
32Knock 2————————
33CAN 2 High————————
34CAN 2 Low————————

Pin map

OEM pointOEM functionOEM familyTarget pointTarget functionTarget familyWire colourEvidence
OEM-A-1Starter signal (term 50)digital_inT8-C2-4Digital 1digital_incorroborated
OEM-A-10Coolant temperature sensortemp_inT8-C2-7Thermistor 1temp_incorroborated
OEM-A-11Idle/WOT throttle switchdigital_inT8-C2-8Digital 2digital_incorroborated
OEM-A-12Injector driver (batch, all 4)injector_outT8-C1-9Injector 1injector_outcorroborated
OEM-A-13GroundgroundT8-C1-13 + T8-C1-14Power Ground 1 + Power Ground 2groundcorroborated
OEM-A-14ECU power (control-unit relay)power_inT8-C1-31Ignition 12v Inpower_incorroborated
OEM-A-16A/C compressor signaldigital_inT8-C2-11Digital 3digital_incorroborated
OEM-A-17AFM potentiometer supplyvrefT8-C2-245v Outputvrefcorroborated
OEM-A-18Hall sender signal (engine speed)trigger_inT8-C2-22Cam 1trigger_incorroborated
OEM-A-19GroundgroundT8-C1-13 + T8-C1-14Power Ground 1 + Power Ground 2groundcorroborated
OEM-A-2Oxygen (lambda) sensor signallambda_nb_inT8-C2-1Analogue 2analog_incorroborated
OEM-A-21AFM signalanalog_inT8-C2-10Analogue 1analog_incorroborated
OEM-A-22Idle stabilizer valve coil 1low_side_outT8-C1-4PWM 2low_side_outcorroborated
OEM-A-23Idle stabilizer valve coil 2low_side_outT8-C1-3PWM 3low_side_outcorroborated
OEM-A-25Ignition timing signal to TCIignition_outT8-C1-10Coil 1ignition_outcorroborated
OEM-A-3Fuel pump relay controllow_side_outT8-C1-5PWM 1low_side_outcorroborated
OEM-A-4Knock sensor signalknock_inT8-C3-31Knock 1knock_incorroborated
OEM-A-5Knock sensor returnsensor_groundT8-C2-21 + T8-C2-33Sensor Ground + Sensor Groundsensor_groundcorroborated
OEM-A-6Sensor ground (CTS/Hall/AFM/throttle)sensor_groundT8-C2-21 + T8-C2-33Sensor Ground + Sensor Groundsensor_groundcorroborated
OEM-A-7Knock sensor shieldshield———corroborated
OEM-A-8Hall sender supply (distributor)power_in———corroborated
OEM-A-9Intake air temperature sensortemp_inT8-C2-25Thermistor 2temp_incorroborated

Cut list

WireFromToGauge (mm²)ColourLengthSignalIdent
W1OEM-A-14SP-14V-10.85no routeECU power (control-unit relay)—
W2SP-14V-1T8-C1-310.85no routeIgnition 12v In—
W3OEM-A-13SP-GND-10.85no routeGround—
W4OEM-A-19SP-GND-10.85no routeGround—
W5SP-GND-1T8-C1-130.85no routePower Ground 1—
W6SP-GND-1T8-C1-140.85no routePower Ground 2—
W7OEM-A-5SP-0V-10.5no routeKnock sensor return—
W8OEM-A-6SP-0V-10.5no routeSensor ground (CTS/Hall/AFM/throttle)—
W9SP-0V-1T8-C2-210.5no routeSensor Ground—
W10SP-0V-1T8-C2-330.5no routeSensor Ground—
W11OEM-A-17T8-C2-240.5no routeAFM potentiometer supply—
W12OEM-A-18T8-C2-220.5no routeHall sender signal (engine speed)—
W13OEM-A-4T8-C3-310.5no routeKnock sensor signal—
W14OEM-A-25T8-C1-100.5no routeIgnition timing signal to TCI—
W15OEM-A-12T8-C1-90.5no routeInjector driver (batch, all 4)—
W16OEM-A-3T8-C1-50.5no routeFuel pump relay control—
W17OEM-A-21T8-C2-100.5no routeAFM signal—
W18OEM-A-10T8-C2-70.5no routeCoolant temperature sensor—
W19OEM-A-22T8-C1-40.5no routeIdle stabilizer valve coil 1—
W20OEM-A-23T8-C1-30.5no routeIdle stabilizer valve coil 2—
W21OEM-A-2T8-C2-10.5no routeOxygen (lambda) sensor signal—
W22OEM-A-9T8-C2-250.5no routeIntake air temperature sensor—
W23OEM-A-1T8-C2-40.5no routeStarter signal (term 50)—
W24OEM-A-11T8-C2-80.5no routeIdle/WOT throttle switch—
W25OEM-A-16T8-C2-110.5no routeA/C compressor signal—

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)20.000ea

ECU setup sheet

RoleEngine refEngine signalSensorECU pointECU functionECU classSetup flag
No configured channels.

Findings

Open (7)

SeverityCodeSubjectMessage
errorPHYS_REQUIRED_OPENT8-C3-26T8-C3-26 "Permanent 12v" is required but not wired.
errorPHYS_REQUIRED_OPENT8-C3-27T8-C3-27 "Permanent 12v" is required but not wired.
errorREQUIRED_UNMAPPEDOEM-A-8Required OEM function "Hall sender supply (distributor)" (power_in) is not connected to the new ECU.
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.
infoUNMAPPEDOEM1 optional OEM pins are not mapped: OEM-A-7 Knock sensor shield

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 8: Hall sender supply (distributor): no rule for class sensor_supply_in; wire by hand - T8-C3 26: Permanent 12v: required by DTAFast T8+ but no stock pin feeds it; wire by hand - T8-C3 27: Permanent 12v: required by DTAFast T8+ but no stock pin feeds it; wire by hand Not wired: - OEM-A 7: Knock sensor shield: no shield pin on DTAFast T8+

Sources

ReliabilityKindTitleURLArchiveCapturedSHA-256
4vendor_docDTAFast T8+ ECU wiring diagramhttps://cdn.shopify.com/s/files/1/0848/7508/4108/files/T8PLUS_Wiring-Diagram.pdf?v=1728572013———
2community_copya2resource: Digifant II engine controller pinout (VW Golf/Jetta Mk2 1.8 8v)http://www.a2resource.com/electrical/management/digifant2.html———
2community_copydrive2.ru: VW Golf Mk2 PF Digifant II ECU pinouthttps://www.drive2.ru/l/9886121———