Audi Workshop Service and Repair Manuals

Compass test The first step in the compass test is an internal check on the compass wiring. The compass directions are then checked whilst driving in a circle. Test requirements: l  Open flat area (maximum gradient 4°) l  Avoid magnetic or electromagnetic fields, i.e. do not drive alongside power lines, past a line of trucks or close to reinforced-concrete structures and not where there is a lot of iron in the vicinity (e.g. scrap, steel scaffolding, etc.). l  Speed approx. 20 ... 30 km/h l  The test circuit ideally takes the form of a circle with a minimum diameter of 30 m; the route may also be rectangular –  Select menu item “COMPASS” with Cursor keys. Indicated on display:

SYSTEM TEST
>	PARAMETERS WHEEL SENSOR COMPASS REAR VOLTAGE INTERNAL

–  Confirm selection by pressing ENTER key. The internal wiring test is now performed. If there are no faults, compass test continues automatically. The following appears in the event of a fault, i.e. no compass data detected: Fault message on display:

NO COMPASS DATA AVAILABLE
>	CONTINUE

–  Press ENTER key to continue. Indicated on display:

CHECK COMPASS AND WIRING
>	OK

–  Use ENTER key to confirm “OK” display. –  Use current flow diagram to check compass wiring and repair if necessary. Re-start compass test → Chapter. Compass test continues automatically if wiring is OK. Indicated on display:

DRIVE SLOWLY IN A CIRCLE
>	START

–  Use ENTER key to confirm “START” display. Indicated on display:

END OF CIRCLE REACHED?
>	OK

–  Drive over test distance, observing test requirements → Chapter. –  Use ENTER key to confirm “OK” display. The following appears on successful completion of compass test: Indicated on display:

COMPASS OK
>	CONTINUE

–  Press ENTER key to continue. If compass test is OK, process continues with testing of heated rear window voltage tap → Chapter. If compass data are not OK, one of the three following causes will be displayed: 1. Cause: “Compass unusable”

COMPASS NOT OK
>	CONTINUE

Recorded compass ellipse unusable (possible causes: magnetic interference and/or defective magnetic field probe) –  Press ENTER key to continue. 2. Cause: “Distance too short”

ERROR: DISTANCE TOO SHORT
>	CONTINUE

Diameter of circle too small and/or vehicle driven at too high a speed –  Press ENTER key to continue and repeat compass test in correct manner → Chapter. 3. Cause: “Circle incomplete”

ERROR: CIRCLE NOT COMPLETE
>	CONTINUE

Full circle not detected –  Press ENTER key to continue and repeat compass test in correct manner → Chapter.