The UK quattro Network
Copyright © The UK quattro Network 2005. All rights reserved
| Pin | Colour | Source/Target |
|---|---|---|
| 1 | Brown/black | To T6 (6-pin white connector) |
| 2 | Yellow/red | 12V from illumination control button |
| 3 | Blue/black | (F4) Resistive link to electronic injection |
| 4 | Purple | Engine speed from ECU |
| 5 | Red/yellow | Speed sensor - four ground pulses per axle revolution |
| 6 | Green | Left tilt of trip computer switch to ground |
| 7 | Green/blue | Right tilt of trip computer switch to ground |
| 8 | Grey/red | To external light sensor |
| 9 | Green/violet | Grounded by reset button of trip computer switch |
| 10 | Yellow/black | 8V to 5V pin of sensor plate potentiometer |
| 11 | White/yellow | 12V from X relay via fuse 16 (with ignition on) |
| 12 | White/yellow | 12V from X relay via fuse 16 (with ignition on) |
| 13 | White | 12V from headlight switch with headlights on |
| 14 | Blue | Alternator terminal D - 12V with ignition on |
| 15 | Black/blue | 12V from ignition switch |
| 16 | Grey/yellow | Grounded by F9, F21, F34 and F75 - brake system problems |
| 17 | White/green | Oil pressure control unit (J150) |
| 18 | Black/green | Right indicator - grounded intermittently when indicator operating |
| 19 | Red/blue | 12V from battery via fuse 4 |
| 20 | Red/blue | 12V from battery via fuse 4 |
| 21 | Brown | Chassis ground |
| 22 | Brown | Chassis ground |
| 23 | Black/red | Enrichment correction from fuel injection control unit - voltage will change |
| 24 | Violet/black | Fuel tank sender - 283 ohms to ground with empty tank, 40 ohms to ground with full tank |
| 25 | White/grey | Dashboard illumination dimmer - 4 ohms to 25 ohms between pins 12 and 25 |
| 26 | Blue/brown | Coolant temperature - 289 ohms to ground at 51°C, 100 ohms to ground at 86°C |
| 27 | Blue/yellow | Coolant overheat - grounded above 120°C coolant temperature - and coolant low |
| 28 | Brown | From -ve pin of air mass potentiometer (ground) |
| 29 | Green/white | Signal from air mass potentiometer. Ca. 1V at idle, increases with rpm |
| 30 | Yellow | External light sensor |
| 31 | Blue/white | 12V if headlights on high beam |
| 32 | (Seat heater indicator on other vehicles) | |
| 33 | Yellow/brown | "Check engine" light |
| 34 | Black/white | Left indicator - grounded intermittently when indicator operating |
| 35 | Grey/white | From rear window heater switch - 12V when on |