PROJEKT36 · WIRING

Airbag, ABS & ASC

The airbag module with its igniters and sensors, the ABS unit fitted without traction control, and the six-cylinder ABS/ASC unit with its throttle actuator. Hover or tap a row to see where the wire goes.

Standard petrol E36 from the 1998 BMW wiring manual. M3 ABS and four-cylinder ASC left out. On a phone, scroll the diagram sideways.

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SW blackRT redGN greenBL blueGE yellowBR brownWS white GN/SW = green with black stripe supply / ground of a part shown elsewhere

Airbag module X74

fuse F42 7.5A ground X1441 0.5 BL/SW cluster X16 pin 14 0.5 WS/VI diagnostic link 0.5 GE/SW clock spring C101 X783 0.5 BL/SW passenger airbag G6 X782 0.5 GE/BR G12 via X11289 0.5 BL/RT G13 via X11290 0.5 BL G14 via X257 pins 25 / 26 0.5 GE G15 via X256 pins 25 / 26 0.35 WS/BL B78 X1885 pin 3 0.35 WS/GE B79 X1886 pin 3 0.5 BL/GN/GE buckle switch S58 X778 pin 3 0.5 WS/RT seat control A113 X10218 pin 3 0.35 BR/SW ZKE X13253 pin 7 / ZVM X13012 pin 14 X74 Airbag module airbag module A12 5 Supply (R) 6 Ground 7 Airbag warning light 9 Diagnosis TxD 10 / 11 Driver airbag + / − 13 / 14 Passenger airbag + / − 1 / 2 Driver belt tensioner 3 / 4 Passenger belt tensioner 16 / 17 Left side airbag 18 / 19 Right side airbag 20 Driver side impact sensor 21 Passenger side impact sensor 12 Driver belt buckle switch 15 Seat occupancy 34 Crash signal

How it works

The airbag module fires the front airbags, the belt tensioners and the side airbags, and reads the side impact sensors, the driver's buckle switch and the passenger seat mat.

Each igniter has its own pair of wires with a shorting bridge in the plug, so an unplugged igniter cannot fire from static.

Check on your car

  • Do not measure igniter circuits with a meter or test lamp: disconnect the battery, wait, and use only the airbag scan tool.
  • Belt buckle switch S58 also lights the seat belt lamp in the cluster (X17 pin 14, 0.5 mm² blue/violet/yellow through X13 pin 15).

Redrawn from BMW ETM 3234.0 (05/99), standard petrol E36 (316i–328i); diesel and M3 parts are left out.

ABS (without ASC)

fuse F10 30A fuse F38 30A fuse F21 5A ground X1165 ground X1165 0.35 GR/SW/GE cluster X17 pin 21 0.35 BL/RT brake light switch, splice X181 0.5 WS/GR/GE DME X6000 pin 15 (320i–328i) 0.35 WS/VI diagnostic link 0.5 BR B2 X114 pins 1 / 2 0.5 GE B1 X113 pins 2 / 1 0.5 BL B4 X142 pins 2 / 1 0.5 GE/SW B3 X143 pins 2 / 1 X11394 ABS control unit ABS control unit A202 25 Valve supply (30) 9 Pump supply (30) 4 Ignition (15) 8 Ground 24 Ground 16 ABS warning lamp 18 Brake light switch (54) 21 Signal from DME 7 Diagnosis TxD 2 / 1 Front left wheel sensor 19 / 20 Front right wheel sensor 6 / 5 Rear left wheel sensor 22 / 23 Rear right wheel sensor

How it works

Late E36s without ASC have the compact ABS (control unit and hydraulic unit in one), fed from F10 for the valves and F38 for the pump.

A wheel sensor is a two-wire coil. Measure its resistance at the unit plug pin pair; a wire broken in the wheel arch shows as open.

Check on your car

  • Drawn from the 1998 manual. Earlier E36s used other ABS units with different plugs; check which unit your car has before using these pin numbers.

Redrawn from BMW ETM 3450.0 (05/99), standard petrol E36 (316i–328i); diesel and M3 parts are left out.

ABS with ASC (six-cylinder)

fuse F10 30A 0.5 GN/BL/GE fuse F21 5A 2.5 RT/BL/GE overvoltage relay K10 pin 8 0.5 BR/SW K10 X54 pin 6 0.5 BR/GR pump relay K75 X1161 pin 6 ground X1166 0.5 GR/SW/GE cluster X17 pin 11 0.5 BL/BR cluster X17 pin 12 0.75 BL/RT brake light switch, splice X181 0.5 BL/VI ASC switch S6 X521 pin 6 0.5 SW DME X6000 pin 36 0.5 WS/GR/GE DME X6000 pin 15 0.5 WS/RT/GE DME X6000 pin 82 0.5 WS/GN DME X6000 pin 80 0.5 WS/GR DME X6000 pin 81 0.5 WS/GR/GE DME X6000 pin 45 0.5 WS/GN/GE EGS X7000 pin 19 2.5 SW/GN/GE actuator M93 X10094 0.5 WS/RT R31 X10239 0.5 WS/VI diagnostic link 0.5 GE B2 X114 pins 2 / 1 0.5 GE B1 X113 pins 2 / 1 0.5 WS B4 X142 pins 2 / 1 0.5 GN B3 X143 pins 2 / 1 0.75 BR/WS/GE Y1 X1176 pins 1 / 2 0.75 BR/GN Y1 X1176 pins 3 / 4 0.75 BR/BL Y1 X1176 pins 18 / 19 0.75 BR/GR/GE Y1 X1176 pins 24 / 25 0.75 BR/BL/GE Y1 X1176 pin 16 0.5 BL Y1 X1176 pins 22 / 21 X1171 ABS/ASC control unit ABS/ASC control unit A52 51 Valve supply (30) 35 Ignition (15) 2 / 16 / 33 Operating voltage 13 Overvoltage relay coil 52 Pump relay coil 1 / 3 / 19 Ground 34 ABS warning lamp 44 ASC warning lamp 32 Brake light switch (54) 27 ASC switch 41 Engine speed (TD) 15 ASC signal to DME 5 EML signal to DME 4 Traction signal from DME 25 Drag torque (MSR) from DME 26 Throttle position to DME 6 Gearbox intervention (auto) 21 / 20 ADS throttle actuator 42 / 43 / 23 ADS potentiometer 7 / 8 Diagnosis TxD / RxD 48 / 30 Front left wheel sensor 47 / 11 Front right wheel sensor 46 / 29 Rear left wheel sensor 45 / 10 Rear right wheel sensor 40 / 54 Front left valves 22 / 37 Front right valves 17 / 18 Rear left valves 39 / 55 Rear right valves 36 Separating valve 49 / 50 Pump motor sensor

How it works

On six-cylinders with ASC, one unit runs ABS and traction control. It cuts power through the DME (ignition and injection) and closes the second throttle valve with the ADS actuator, and brakes the spinning wheel through the separating valve.

The overvoltage protection relay K10 feeds the unit and the hydraulic unit; when it drops out, both ABS and ASC lamps come on through diode V7.

Check on your car

  • The pin table names pins 39 and 55 "rear left"; the schematic draws them to the rear right valves (4). Drawn as the schematic.

Redrawn from BMW ETM 3450.1 (05/99), standard petrol E36 (316i–328i); diesel and M3 parts are left out.

Reading the wire codes

BMW labels every wire with its size and colour, for example 2.5 SW/GE: 2.5 mm², black (schwarz) with a yellow (gelb) stripe. Connectors are numbered X…, followed by the pin. The wires in these diagrams are drawn at relative thickness, so the 25 mm² battery cable stands out from a 0.35 mm² signal wire.

Codes used here: SW = black, RT = red, GN = green, BL = blue, GE = yellow, BR = brown, WS = white.