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BMW 3 Series E36 1990–2000 (M50/M52) → Emtron SL8 (auto)

BMW 3 Series E36 1990–2000 (M50/M52) — Emtron — SL8
⚠ NOT CHECKED. Don't build from this.
Drawn by Michael Gnankou · Rev 0 · draft · 2026-10-08

Before you start

Statusdraft · not yet verified: nobody has reported building and running this harness
Open errorsnone
Size of the job52 wires · 7 connectors · 4 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-X-54SP-14V-10.85☐☐☐☐☐☐☐
W2SP-14V-1SL8-A-340.85☐☐☐☐☐☐☐
W3SP-14V-1SL8-B-10.85☐☐☐☐☐☐☐
W4OEM-X-15SP-GND-10.85☐☐☐☐☐☐☐
W5OEM-X-34SP-GND-10.85☐☐☐☐☐☐☐
W6OEM-X-55SP-GND-10.85☐☐☐☐☐☐☐
W7OEM-X-6SP-GND-10.85☐☐☐☐☐☐☐
W8SP-GND-1SL8-B-180.85☐☐☐☐☐☐☐
W9SP-GND-1SL8-B-260.85☐☐☐☐☐☐☐
W10OEM-X-28SP-0V-10.5☐☐☐☐☐☐☐
W11OEM-X-40SP-0V-10.5☐☐☐☐☐☐☐
W12OEM-X-43SP-0V-10.5☐☐☐☐☐☐☐
W13OEM-X-44SP-0V-10.5☐☐☐☐☐☐☐
W14OEM-X-71SP-0V-10.5☐☐☐☐☐☐☐
W15SP-0V-1SL8-B-100.5☐☐☐☐☐☐☐
W16OEM-X-59SL8-B-20.5☐☐☐☐☐☐☐
W17OEM-X-16SL8-B-50.5☐☐☐☐☐☐☐
W18SP-0V-1SL8-B-60.5☐☐☐☐☐☐☐
W19OEM-X-17SL8-B-70.5☐☐☐☐☐☐☐
W20SP-0V-1SL8-B-80.5☐☐☐☐☐☐☐
W21OEM-X-70SL8-B-160.5☐☐☐☐☐☐☐
W22OEM-X-69SL8-B-240.5☐☐☐☐☐☐☐
W23OEM-X-50SL8-A-260.5☐☐☐☐☐☐☐
W24OEM-X-51SL8-A-270.5☐☐☐☐☐☐☐
W25OEM-X-52SL8-A-280.5☐☐☐☐☐☐☐
W26OEM-X-23SL8-A-290.5☐☐☐☐☐☐☐
W27OEM-X-25SL8-A-300.5☐☐☐☐☐☐☐
W28OEM-X-24SL8-A-310.5☐☐☐☐☐☐☐
W29OEM-X-33SL8-A-10.5☐☐☐☐☐☐☐
W30OEM-X-32SL8-A-20.5☐☐☐☐☐☐☐
W31OEM-X-31SL8-A-30.5☐☐☐☐☐☐☐
W32OEM-X-5SL8-A-40.5☐☐☐☐☐☐☐
W33OEM-X-3SL8-A-50.5☐☐☐☐☐☐☐
W34OEM-X-4SL8-A-60.5☐☐☐☐☐☐☐
W35OEM-X-45SP-SHD-10.5☐☐☐☐☐☐☐
W36SP-SHD-1SL8-B-90.5☐☐☐☐☐☐☐
W37OEM-X-56SL8-B-40.5☐☐☐☐☐☐☐
W38OEM-X-1SL8-B-30.5☐☐☐☐☐☐☐
W39OEM-X-27SL8-A-140.5☐☐☐☐☐☐☐
W40OEM-X-38SL8-A-150.5☐☐☐☐☐☐☐
W41OEM-X-2SL8-A-160.5☐☐☐☐☐☐☐
W42OEM-X-29SL8-A-170.5☐☐☐☐☐☐☐
W43OEM-X-36SL8-A-100.5☐☐☐☐☐☐☐
W44OEM-X-7SL8-A-110.5☐☐☐☐☐☐☐
W45OEM-X-8SL8-A-120.5☐☐☐☐☐☐☐
W46OEM-X-47SL8-A-130.5☐☐☐☐☐☐☐
W47OEM-X-41SL8-B-110.5☐☐☐☐☐☐☐
W48OEM-X-73SL8-B-120.5☐☐☐☐☐☐☐
W49OEM-X-13SL8-B-130.5☐☐☐☐☐☐☐
W50OEM-X-78SL8-B-140.5☐☐☐☐☐☐☐
W51OEM-X-77SL8-B-150.5☐☐☐☐☐☐☐
W52OEM-X-42SL8-A-200.5☐☐☐☐☐☐☐

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
1SL8-A-34SL8-B-2open (OL)+12 V supply must not touch 5 V sensor reference
2SL8-B-10SL8-A-34open (OL)sensor ground must not touch +12 V supply
3SL8-B-10SL8-B-2open (OL)sensor ground must not touch 5 V sensor reference
4SL8-B-18SL8-A-34open (OL)power ground must not touch +12 V supply
5SL8-B-18SL8-B-2open (OL)power ground must not touch 5 V sensor reference

Revisions

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Schematic

OEM-XSL8-ASL8-BSP-0VSP-14VSP-GNDSP-SHD

Connectors

OEM-X

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Fuel pump relay control—W38—0.5SL8-B-3———
13O2 sensor signal—W49—0.5SL8-B-13———
15Ground—W4—0.85SP-GND-1———
16Crank position sensor (+)—W17—0.5SL8-B-5———
17Camshaft position sensor (Hall)—W19—0.5SL8-B-7———
2Idle speed control valve (close winding)—W41—0.5SL8-A-16———
23Ignition coil cylinder 4—W26—0.5SL8-A-29———
24Ignition coil cylinder 6—W28—0.5SL8-A-31———
25Ignition coil cylinder 5—W27—0.5SL8-A-30———
26Battery voltage (constant +12V)————————
27Main relay control—W39—0.5SL8-A-14———
28Ground (electronics + sensor shielding)—W10—0.5SP-0V-1———
29Idle speed control valve (open winding)—W42—0.5SL8-A-17———
3Injector cylinder 5—W33—0.5SL8-A-5———
31Injector cylinder 3—W31—0.5SL8-A-3———
32Injector cylinder 2—W30—0.5SL8-A-2———
33Injector cylinder 1—W29—0.5SL8-A-1———
34Ground (output stages)—W5—0.85SP-GND-1———
36Evap purge solenoid—W43—0.5SL8-A-10———
38O2 sensor heater relay control—W40—0.5SL8-A-15———
4Injector cylinder 6—W34—0.5SL8-A-6———
40O2 sensor signal ground—W11—0.5SP-0V-1———
41Mass air flow (MAF) signal—W47—0.5SL8-B-11———
42Vehicle speed signal—W52—0.5SL8-A-20———
43Crank position sensor (-)—W12—0.5SP-0V-1———
44Sensor ground (IAT/ECT/TPS)—W13—0.5SP-0V-1———
45Shield ground—W35—0.5SP-SHD-1———
47Tachometer output—W46—0.5SL8-A-13———
5Injector cylinder 4—W32—0.5SL8-A-4———
50Ignition coil cylinder 1—W23—0.5SL8-A-26———
51Ignition coil cylinder 2—W24—0.5SL8-A-27———
52Ignition coil cylinder 3—W25—0.5SL8-A-28———
54ECU power (+14V from main relay)—W1—0.85SP-14V-1———
55Ground (ignition)—W6—0.85SP-GND-1———
56Ignition switch (terminal 15)—W37—0.5SL8-B-4———
59+5V sensor supply—W16—0.5SL8-B-2———
6Ground (injector output stages)—W7—0.85SP-GND-1———
69Knock sensor cylinders 4-6—W22—0.5SL8-B-24———
7VANOS intake camshaft solenoid—W44—0.5SL8-A-11———
70Knock sensor cylinders 1-3—W21—0.5SL8-B-16———
71Knock sensor ground/shield—W14—0.5SP-0V-1———
73Throttle position (TPS)—W48—0.5SL8-B-12———
77Intake air temperature (IAT)—W51—0.5SL8-B-15———
78Engine coolant temperature (ECT)—W50—0.5SL8-B-14———
8Check engine light (MIL)—W45—0.5SL8-A-12———

SL8-A

Mating face
SL8-A-1 · Injection channel 11SL8-A-2 · Injection channel 22SL8-A-3 · Injection channel 33SL8-A-4 · Injection channel 44SL8-A-5 · Injection channel 55SL8-A-6 · Injection channel 66SL8-A-7 · Injection channel 77SL8-A-8 · Injection channel 88SL8-A-9 · Sensor supply 8V9SL8-A-10 · Auxiliary output 110SL8-A-11 · Auxiliary output 211SL8-A-12 · Auxiliary output 312SL8-A-13 · Auxiliary output 413SL8-A-14 · Auxiliary output 514SL8-A-15 · Auxiliary output 615SL8-A-16 · Auxiliary output 716SL8-A-17 · Auxiliary output 817SL8-A-18 · Auxiliary output 918SL8-A-19 · Auxiliary output 1019SL8-A-20 · Digital input 120SL8-A-21 · Digital input 221SL8-A-22 · Digital input 322SL8-A-23 · Digital input 423SL8-A-24 · Digital input 524SL8-A-25 · Digital input 625SL8-A-26 · Ignition channel 126SL8-A-27 · Ignition channel 227SL8-A-28 · Ignition channel 328SL8-A-29 · Ignition channel 429SL8-A-30 · Ignition channel 530SL8-A-31 · Ignition channel 631SL8-A-32 · Ignition channel 732SL8-A-33 · Ignition channel 833SL8-A-34 · Aux 9–10 14V supply34
Wire side
SL8-A-1 · Injection channel 11SL8-A-2 · Injection channel 22SL8-A-3 · Injection channel 33SL8-A-4 · Injection channel 44SL8-A-5 · Injection channel 55SL8-A-6 · Injection channel 66SL8-A-7 · Injection channel 77SL8-A-8 · Injection channel 88SL8-A-9 · Sensor supply 8V9SL8-A-10 · Auxiliary output 110SL8-A-11 · Auxiliary output 211SL8-A-12 · Auxiliary output 312SL8-A-13 · Auxiliary output 413SL8-A-14 · Auxiliary output 514SL8-A-15 · Auxiliary output 615SL8-A-16 · Auxiliary output 716SL8-A-17 · Auxiliary output 817SL8-A-18 · Auxiliary output 918SL8-A-19 · Auxiliary output 1019SL8-A-20 · Digital input 120SL8-A-21 · Digital input 221SL8-A-22 · Digital input 322SL8-A-23 · Digital input 423SL8-A-24 · Digital input 524SL8-A-25 · Digital input 625SL8-A-26 · Ignition channel 126SL8-A-27 · Ignition channel 227SL8-A-28 · Ignition channel 328SL8-A-29 · Ignition channel 429SL8-A-30 · Ignition channel 530SL8-A-31 · Ignition channel 631SL8-A-32 · Ignition channel 732SL8-A-33 · Ignition channel 833SL8-A-34 · Aux 9–10 14V supply34
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1Injection channel 1—W29—0.5OEM-X-33———
2Injection channel 2—W30—0.5OEM-X-32———
3Injection channel 3—W31—0.5OEM-X-31———
4Injection channel 4—W32—0.5OEM-X-5———
5Injection channel 5—W33—0.5OEM-X-3———
6Injection channel 6—W34—0.5OEM-X-4———
7Injection channel 7————————
8Injection channel 8————————
9Sensor supply 8V————————
10Auxiliary output 1—W43—0.5OEM-X-36———
11Auxiliary output 2—W44—0.5OEM-X-7———
12Auxiliary output 3—W45—0.5OEM-X-8———
13Auxiliary output 4—W46—0.5OEM-X-47———
14Auxiliary output 5—W39—0.5OEM-X-27———
15Auxiliary output 6—W40—0.5OEM-X-38———
16Auxiliary output 7—W41—0.5OEM-X-2———
17Auxiliary output 8—W42—0.5OEM-X-29———
18Auxiliary output 9————————
19Auxiliary output 10————————
20Digital input 1—W52—0.5OEM-X-42———
21Digital input 2————————
22Digital input 3————————
23Digital input 4————————
24Digital input 5————————
25Digital input 6————————
26Ignition channel 1—W23—0.5OEM-X-50———
27Ignition channel 2—W24—0.5OEM-X-51———
28Ignition channel 3—W25—0.5OEM-X-52———
29Ignition channel 4—W26—0.5OEM-X-23———
30Ignition channel 5—W27—0.5OEM-X-25———
31Ignition channel 6—W28—0.5OEM-X-24———
32Ignition channel 7————————
33Ignition channel 8————————
34Aux 9–10 14V supply—W2—0.85SP-14V-1———

SL8-B

Mating face
SL8-B-1 · ECU 14V supply1SL8-B-2 · Sensor supply Vref1 5.0V2SL8-B-3 · EFI relay output (low side, 200 mA)3SL8-B-4 · Ignition switch input4SL8-B-5 · Crank index sensor +5SL8-B-6 · Crank index sensor −6SL8-B-7 · Sync sensor +7SL8-B-8 · Sync sensor −8SL8-B-9 · Shield (crank/sync/knock)9SL8-B-10 · Analog sensor 0V reference10SL8-B-11 · Analog input 111SL8-B-12 · Analog input 212SL8-B-13 · Analog input 313SL8-B-14 · Analog input 414SL8-B-15 · Analog input 515SL8-B-16 · Knock 1 +16SL8-B-17 · Knock 1 −17SL8-B-18 · ECU ground18SL8-B-19 · Analog input 619SL8-B-20 · Analog input 7 (switchable 1k pull-up)20SL8-B-21 · Analog input 8 (switchable 1k pull-up)21SL8-B-22 · Analog input 9 (switchable 1k pull-up)22SL8-B-23 · Analog input 10 (switchable 1k pull-up)23SL8-B-24 · Knock 2 +24SL8-B-25 · Knock 2 −25SL8-B-26 · ECU ground26SL8-B-27 · CAN 1 H27SL8-B-28 · CAN 1 L28SL8-B-29 · NC29SL8-B-30 · NC30SL8-B-31 · Ethernet Tx +31SL8-B-32 · Ethernet Tx −32SL8-B-33 · Ethernet Rx +33SL8-B-34 · Ethernet Rx −34
Wire side
SL8-B-1 · ECU 14V supply1SL8-B-2 · Sensor supply Vref1 5.0V2SL8-B-3 · EFI relay output (low side, 200 mA)3SL8-B-4 · Ignition switch input4SL8-B-5 · Crank index sensor +5SL8-B-6 · Crank index sensor −6SL8-B-7 · Sync sensor +7SL8-B-8 · Sync sensor −8SL8-B-9 · Shield (crank/sync/knock)9SL8-B-10 · Analog sensor 0V reference10SL8-B-11 · Analog input 111SL8-B-12 · Analog input 212SL8-B-13 · Analog input 313SL8-B-14 · Analog input 414SL8-B-15 · Analog input 515SL8-B-16 · Knock 1 +16SL8-B-17 · Knock 1 −17SL8-B-18 · ECU ground18SL8-B-19 · Analog input 619SL8-B-20 · Analog input 7 (switchable 1k pull-up)20SL8-B-21 · Analog input 8 (switchable 1k pull-up)21SL8-B-22 · Analog input 9 (switchable 1k pull-up)22SL8-B-23 · Analog input 10 (switchable 1k pull-up)23SL8-B-24 · Knock 2 +24SL8-B-25 · Knock 2 −25SL8-B-26 · ECU ground26SL8-B-27 · CAN 1 H27SL8-B-28 · CAN 1 L28SL8-B-29 · NC29SL8-B-30 · NC30SL8-B-31 · Ethernet Tx +31SL8-B-32 · Ethernet Tx −32SL8-B-33 · Ethernet Rx +33SL8-B-34 · Ethernet Rx −34
CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1ECU 14V supply—W3—0.85SP-14V-1———
2Sensor supply Vref1 5.0V—W16—0.5OEM-X-59———
3EFI relay output (low side, 200 mA)—W38—0.5OEM-X-1———
4Ignition switch input—W37—0.5OEM-X-56———
5Crank index sensor +—W17—0.5OEM-X-16———
6Crank index sensor −—W18—0.5SP-0V-1———
7Sync sensor +—W19—0.5OEM-X-17———
8Sync sensor −—W20—0.5SP-0V-1———
9Shield (crank/sync/knock)—W36—0.5SP-SHD-1———
10Analog sensor 0V reference—W15—0.5SP-0V-1———
11Analog input 1—W47—0.5OEM-X-41———
12Analog input 2—W48—0.5OEM-X-73———
13Analog input 3—W49—0.5OEM-X-13———
14Analog input 4—W50—0.5OEM-X-78———
15Analog input 5—W51—0.5OEM-X-77———
16Knock 1 +—W21—0.5OEM-X-70———
17Knock 1 −————————
18ECU ground—W8—0.85SP-GND-1———
19Analog input 6————————
20Analog input 7 (switchable 1k pull-up)————————
21Analog input 8 (switchable 1k pull-up)————————
22Analog input 9 (switchable 1k pull-up)————————
23Analog input 10 (switchable 1k pull-up)————————
24Knock 2 +—W22—0.5OEM-X-69———
25Knock 2 −————————
26ECU ground—W9—0.85SP-GND-1———
27CAN 1 H————————
28CAN 1 L————————
29NC————————
30NC————————
31Ethernet Tx +————————
32Ethernet Tx −————————
33Ethernet Rx +————————
34Ethernet Rx −————————

SP-0V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W15—0.5SL8-B-10———
1——W10—0.5OEM-X-28———
1——W11—0.5OEM-X-40———
1——W12—0.5OEM-X-43———
1——W13—0.5OEM-X-44———
1——W14—0.5OEM-X-71———
1——W18—0.5SL8-B-6———
1——W20—0.5SL8-B-8———

SP-14V

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W1—0.85OEM-X-54———
1——W2—0.85SL8-A-34———
1——W3—0.85SL8-B-1———

SP-GND

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W4—0.85OEM-X-15———
1——W5—0.85OEM-X-34———
1——W6—0.85OEM-X-55———
1——W7—0.85OEM-X-6———
1——W8—0.85SL8-B-18———
1——W9—0.85SL8-B-26———

SP-SHD

CavityFunctionSignalWireColourGauge (mm²)DestinationTerminalSealPlug
1——W35—0.5OEM-X-45———
1——W36—0.5SL8-B-9———

Pin map

OEM pointOEM functionOEM familyTarget pointTarget functionTarget familyWire colourEvidence
OEM-X-1Fuel pump relay controllow_side_outSL8-B-3EFI relay output (low side, 200 mA)low_side_outcorroborated
OEM-X-13O2 sensor signallambda_nb_inSL8-B-13Analog input 3analog_incorroborated
OEM-X-15GroundgroundSL8-B-18 + SL8-B-26ECU ground + ECU groundgroundcorroborated
OEM-X-16Crank position sensor (+)trigger_inSL8-B-5Crank index sensor +trigger_incorroborated
OEM-X-17Camshaft position sensor (Hall)trigger_inSL8-B-7Sync sensor +trigger_incorroborated
OEM-X-2Idle speed control valve (close winding)low_side_outSL8-A-16Auxiliary output 7switch_outcorroborated
OEM-X-23Ignition coil cylinder 4ignition_outSL8-A-29Ignition channel 4ignition_outcorroborated
OEM-X-24Ignition coil cylinder 6ignition_outSL8-A-31Ignition channel 6ignition_outcorroborated
OEM-X-25Ignition coil cylinder 5ignition_outSL8-A-30Ignition channel 5ignition_outcorroborated
OEM-X-26Battery voltage (constant +12V)power_in———corroborated
OEM-X-27Main relay controllow_side_outSL8-A-14Auxiliary output 5switch_outcorroborated
OEM-X-28Ground (electronics + sensor shielding)sensor_groundSL8-B-10 + SL8-B-6 + SL8-B-8Analog sensor 0V reference + Crank index sensor − + Sync sensor −sensor_ground + trigger_incorroborated
OEM-X-29Idle speed control valve (open winding)low_side_outSL8-A-17Auxiliary output 8switch_outcorroborated
OEM-X-3Injector cylinder 5injector_outSL8-A-5Injection channel 5injector_outcorroborated
OEM-X-31Injector cylinder 3injector_outSL8-A-3Injection channel 3injector_outcorroborated
OEM-X-32Injector cylinder 2injector_outSL8-A-2Injection channel 2injector_outcorroborated
OEM-X-33Injector cylinder 1injector_outSL8-A-1Injection channel 1injector_outcorroborated
OEM-X-34Ground (output stages)groundSL8-B-18 + SL8-B-26ECU ground + ECU groundgroundcorroborated
OEM-X-36Evap purge solenoidlow_side_outSL8-A-10Auxiliary output 1switch_outcorroborated
OEM-X-38O2 sensor heater relay controllow_side_outSL8-A-15Auxiliary output 6switch_outcorroborated
OEM-X-4Injector cylinder 6injector_outSL8-A-6Injection channel 6injector_outcorroborated
OEM-X-40O2 sensor signal groundsensor_groundSL8-B-10 + SL8-B-6 + SL8-B-8Analog sensor 0V reference + Crank index sensor − + Sync sensor −sensor_ground + trigger_incorroborated
OEM-X-41Mass air flow (MAF) signalanalog_inSL8-B-11Analog input 1analog_incorroborated
OEM-X-42Vehicle speed signaldigital_inSL8-A-20Digital input 1digital_incorroborated
OEM-X-43Crank position sensor (-)sensor_groundSL8-B-10 + SL8-B-6 + SL8-B-8Analog sensor 0V reference + Crank index sensor − + Sync sensor −sensor_ground + trigger_incorroborated
OEM-X-44Sensor ground (IAT/ECT/TPS)sensor_groundSL8-B-10 + SL8-B-6 + SL8-B-8Analog sensor 0V reference + Crank index sensor − + Sync sensor −sensor_ground + trigger_incorroborated
OEM-X-45Shield groundshieldSL8-B-9Shield (crank/sync/knock)shieldcorroborated
OEM-X-47Tachometer outputtacho_outSL8-A-13Auxiliary output 4switch_outcorroborated
OEM-X-5Injector cylinder 4injector_outSL8-A-4Injection channel 4injector_outcorroborated
OEM-X-50Ignition coil cylinder 1ignition_outSL8-A-26Ignition channel 1ignition_outcorroborated
OEM-X-51Ignition coil cylinder 2ignition_outSL8-A-27Ignition channel 2ignition_outcorroborated
OEM-X-52Ignition coil cylinder 3ignition_outSL8-A-28Ignition channel 3ignition_outcorroborated
OEM-X-54ECU power (+14V from main relay)power_inSL8-A-34 + SL8-B-1Aux 9–10 14V supply + ECU 14V supplypower_incorroborated
OEM-X-55Ground (ignition)groundSL8-B-18 + SL8-B-26ECU ground + ECU groundgroundcorroborated
OEM-X-56Ignition switch (terminal 15)digital_inSL8-B-4Ignition switch inputdigital_incorroborated
OEM-X-59+5V sensor supplyvrefSL8-B-2Sensor supply Vref1 5.0Vvrefcorroborated
OEM-X-6Ground (injector output stages)groundSL8-B-18 + SL8-B-26ECU ground + ECU groundgroundcorroborated
OEM-X-69Knock sensor cylinders 4-6knock_inSL8-B-24Knock 2 +knock_incorroborated
OEM-X-7VANOS intake camshaft solenoidlow_side_outSL8-A-11Auxiliary output 2switch_outcorroborated
OEM-X-70Knock sensor cylinders 1-3knock_inSL8-B-16Knock 1 +knock_incorroborated
OEM-X-71Knock sensor ground/shieldsensor_groundSL8-B-10 + SL8-B-6 + SL8-B-8Analog sensor 0V reference + Crank index sensor − + Sync sensor −sensor_ground + trigger_incorroborated
OEM-X-73Throttle position (TPS)analog_inSL8-B-12Analog input 2analog_incorroborated
OEM-X-77Intake air temperature (IAT)temp_inSL8-B-15Analog input 5analog_incorroborated
OEM-X-78Engine coolant temperature (ECT)temp_inSL8-B-14Analog input 4analog_incorroborated
OEM-X-8Check engine light (MIL)low_side_outSL8-A-12Auxiliary output 3switch_outcorroborated

Cut list

WireFromToGauge (mm²)ColourLengthSignalIdent
W1OEM-X-54SP-14V-10.85no routeECU power (+14V from main relay)—
W2SP-14V-1SL8-A-340.85no routeAux 9–10 14V supply—
W3SP-14V-1SL8-B-10.85no routeECU 14V supply—
W4OEM-X-15SP-GND-10.85no routeGround—
W5OEM-X-34SP-GND-10.85no routeGround (output stages)—
W6OEM-X-55SP-GND-10.85no routeGround (ignition)—
W7OEM-X-6SP-GND-10.85no routeGround (injector output stages)—
W8SP-GND-1SL8-B-180.85no routeECU ground—
W9SP-GND-1SL8-B-260.85no routeECU ground—
W10OEM-X-28SP-0V-10.5no routeGround (electronics + sensor shielding)—
W11OEM-X-40SP-0V-10.5no routeO2 sensor signal ground—
W12OEM-X-43SP-0V-10.5no routeCrank position sensor (-)—
W13OEM-X-44SP-0V-10.5no routeSensor ground (IAT/ECT/TPS)—
W14OEM-X-71SP-0V-10.5no routeKnock sensor ground/shield—
W15SP-0V-1SL8-B-100.5no routeAnalog sensor 0V reference—
W16OEM-X-59SL8-B-20.5no route+5V sensor supply—
W17OEM-X-16SL8-B-50.5no routeCrank position sensor (+)—
W18SP-0V-1SL8-B-60.5no routeCrank index sensor −—
W19OEM-X-17SL8-B-70.5no routeCamshaft position sensor (Hall)—
W20SP-0V-1SL8-B-80.5no routeSync sensor −—
W21OEM-X-70SL8-B-160.5no routeKnock sensor cylinders 1-3—
W22OEM-X-69SL8-B-240.5no routeKnock sensor cylinders 4-6—
W23OEM-X-50SL8-A-260.5no routeIgnition coil cylinder 1—
W24OEM-X-51SL8-A-270.5no routeIgnition coil cylinder 2—
W25OEM-X-52SL8-A-280.5no routeIgnition coil cylinder 3—
W26OEM-X-23SL8-A-290.5no routeIgnition coil cylinder 4—
W27OEM-X-25SL8-A-300.5no routeIgnition coil cylinder 5—
W28OEM-X-24SL8-A-310.5no routeIgnition coil cylinder 6—
W29OEM-X-33SL8-A-10.5no routeInjector cylinder 1—
W30OEM-X-32SL8-A-20.5no routeInjector cylinder 2—
W31OEM-X-31SL8-A-30.5no routeInjector cylinder 3—
W32OEM-X-5SL8-A-40.5no routeInjector cylinder 4—
W33OEM-X-3SL8-A-50.5no routeInjector cylinder 5—
W34OEM-X-4SL8-A-60.5no routeInjector cylinder 6—
W35OEM-X-45SP-SHD-10.5no routeShield ground—
W36SP-SHD-1SL8-B-90.5no routeShield (crank/sync/knock)—
W37OEM-X-56SL8-B-40.5no routeIgnition switch (terminal 15)—
W38OEM-X-1SL8-B-30.5no routeFuel pump relay control—
W39OEM-X-27SL8-A-140.5no routeMain relay control—
W40OEM-X-38SL8-A-150.5no routeO2 sensor heater relay control—
W41OEM-X-2SL8-A-160.5no routeIdle speed control valve (close winding)—
W42OEM-X-29SL8-A-170.5no routeIdle speed control valve (open winding)—
W43OEM-X-36SL8-A-100.5no routeEvap purge solenoid—
W44OEM-X-7SL8-A-110.5no routeVANOS intake camshaft solenoid—
W45OEM-X-8SL8-A-120.5no routeCheck engine light (MIL)—
W46OEM-X-47SL8-A-130.5no routeTachometer output—
W47OEM-X-41SL8-B-110.5no routeMass air flow (MAF) signal—
W48OEM-X-73SL8-B-120.5no routeThrottle position (TPS)—
W49OEM-X-13SL8-B-130.5no routeO2 sensor signal—
W50OEM-X-78SL8-B-140.5no routeEngine coolant temperature (ECT)—
W51OEM-X-77SL8-B-150.5no routeIntake air temperature (IAT)—
W52OEM-X-42SL8-A-200.5no routeVehicle speed signal—

Bill of materials

CategoryPart numberManufacturerDescriptionQtyUnit
connector4-1437290-0TESuperseal 1.0 34-way plug, Key 11.000ea
connector4-1437290-1TESuperseal 1.0 34-way plug, Key 21.000ea
connectorBMW-E36-DME-CONNBMWE36 DME (M3.1/M3.3.1) harness connector1.000ea
terminal3-1447221-4TESuperseal 1.0 socket terminal, 20 AWG (0.5 sq mm)41.000ea

ECU setup sheet

RoleEngine refEngine signalSensorECU pointECU functionECU classSetup flag
No configured channels.

Findings

Open (11)

SeverityCodeSubjectMessage
infoNET_FAMILYOEM-X-2 ↔ SL8-A-16OEM-X-2 "Idle speed control valve (close winding)" [low_side_out] is wired to SL8-A-16 "Auxiliary output 7" [switch_out]. Configure this output as low side.
infoNET_FAMILYOEM-X-27 ↔ SL8-A-14OEM-X-27 "Main relay control" [low_side_out] is wired to SL8-A-14 "Auxiliary output 5" [switch_out]. Configure this output as low side.
infoNET_FAMILYOEM-X-29 ↔ SL8-A-17OEM-X-29 "Idle speed control valve (open winding)" [low_side_out] is wired to SL8-A-17 "Auxiliary output 8" [switch_out]. Configure this output as low side.
infoNET_FAMILYOEM-X-36 ↔ SL8-A-10OEM-X-36 "Evap purge solenoid" [low_side_out] is wired to SL8-A-10 "Auxiliary output 1" [switch_out]. Configure this output as low side.
infoNET_FAMILYOEM-X-38 ↔ SL8-A-15OEM-X-38 "O2 sensor heater relay control" [low_side_out] is wired to SL8-A-15 "Auxiliary output 6" [switch_out]. Configure this output as low side.
infoNET_FAMILYOEM-X-47 ↔ SL8-A-13OEM-X-47 "Tachometer output" [tacho_out] is wired to SL8-A-13 "Auxiliary output 4" [switch_out]. Frequency output on a general output: set it up as a tacho/frequency output with the right pull-up.
infoNET_FAMILYOEM-X-7 ↔ SL8-A-11OEM-X-7 "VANOS intake camshaft solenoid" [low_side_out] is wired to SL8-A-11 "Auxiliary output 2" [switch_out]. Configure this output as low side.
infoNET_FAMILYOEM-X-77 ↔ SL8-B-15OEM-X-77 "Intake air temperature (IAT)" [temp_in] is wired to SL8-B-15 "Analog input 5" [analog_in]. Thermistor on a plain analog input needs a pull-up; check the channel can enable one.
infoNET_FAMILYOEM-X-78 ↔ SL8-B-14OEM-X-78 "Engine coolant temperature (ECT)" [temp_in] is wired to SL8-B-14 "Analog input 4" [analog_in]. Thermistor on a plain analog input needs a pull-up; check the channel can enable one.
infoNET_FAMILYOEM-X-8 ↔ SL8-A-12OEM-X-8 "Check engine light (MIL)" [low_side_out] is wired to SL8-A-12 "Auxiliary output 3" [switch_out]. Configure this output as low side.
infoNET_FAMILYSL8-B-8 ↔ SL8-B-10SL8-B-8 "Sync sensor −" [trigger_in] is wired to SL8-B-10 "Analog sensor 0V reference" [sensor_ground]. Trigger return tied to sensor/trigger ground: correct for single-ended trigger inputs.

Accepted (1)

CodeSubjectReasonBy
REQUIRED_UNMAPPEDOEM-X-26Battery-constant (memory) feed of the stock ECU: the new ECU has no such input, so it is not needed.mapping-proposal

Notes

Fit check: unconfirmed. Confirm these before building: - Trigger pattern for BMW M50 not found in the ECU's docs (SL-series lists only generic Crank Index + Sync inputs; no BMW trigger preset) - This car has EWS-II/III (late E36) immobilizer; needs a delete/bypass Auto-mapped by auto_map() from the library pin data on 2026-10-06. Review every wire against both manuals before building. Not wired: - OEM-X 26: Battery voltage (constant +12V): Emtron SL8 has no battery-constant input; not needed - SL8-B 17: Knock 1 − left open: the stock knock sensor has one ECU wire; check the ECU manual for single-wire knock sensors - SL8-B 25: Knock 2 − left open: the stock knock sensor has one ECU wire; check the ECU manual for single-wire knock sensors

Sources

ReliabilityKindTitleURLArchiveCapturedSHA-256
4vendor_docEmtron SL4/SL6/SL8 ECU datasheetshttps://docs.emtronaustralia.com.au/engine-management/datasheets/index.htmlarchive2026-10-051e22846cec94
4vendor_docEmtron SL4/SL6/SL8 pinout pageshttps://docs.emtronaustralia.com.au/engine-management/wiring/index.htmlarchive2026-10-05e52b3da9996a
4vendor_docLink BMWLink E36X (G4X) plug-in install manualhttps://linkecu.com/documentation/E36X.pdfarchive2026-10-05010cda3acd08
2community_copybimmer-service: Bosch Motronic M3.3.1 pinout (E36 M50)https://www.bimmer-service.com/2025/11/17/bosch-motronic-m3-3-1-pinout-wiring-diagram/———