Table of contents: General information ↓ Replacing lamps ↓ Starter block ↓ Front ride height sensor ↓ Rear ride height sensor ↓ Electronic control unit ↓
General information
1. Xenon headlights are installed on all A4 models as optional equipment. The headlights are equipped with gas-discharge lamps that operate on the principle of an electric arc, instead of heating the filament in conventional halogen lamps. The arc is generated by a starter circuit operating at high voltages. The radiation intensity of such a lamp implies dynamic control of the direction of light, so as not to blind other road users. The control unit monitors the dive of the car and its overall height above the road, receiving signals from sensors installed in the front and rear suspensions. Accordingly, adjusting the direction of the light flow of the headlight using servomotors installed in them.
Warning! Xenon headlights operate at high voltages. Before starting work, to avoid electric shock, disconnect the ground wire from the battery.
Replacing lamps
High beam and side lights
2. Replacing the bulbs is similar to the operation for conventional halogen headlights, as described in paragraph 7.
Low beam
3. Disconnect the ground wire from the battery.
4. Open the cover at the rear of the headlight.
5. Disconnect the wiring connector at the rear of the headlight. To disconnect, turn the locking ring counterclockwise.
6. Remove the bulb from the headlight.
7. Being careful not to touch the bulb, install the new bulb, aligning the notch on the bulb base with the protrusion at the rear of the headlight.
8. Install the locking ring by aligning the notches with the corresponding projections on the back of the pump flange and turn the ring clockwise to secure it.
9. Attach the connector and install the cover. Connect the battery.
Starter block
Removal
10. Disconnect the ground wire from the battery.
11. Open the cover at the rear of the headlight.
12. Disconnect the electrical connector at the rear of the headlight.
13. Press the tabs to release the bushing and pull the wiring out through the rear cover of the starter unit.
14. Disconnect the wiring connector from the starter unit.
15. Loosen the screw and detach the mounting bracket at the rear of the headlight.
16. Remove the starter unit from the headlight.
Installation
17. Installation - reverse procedure.
Front ride height sensor
Removal
18. The sensor is installed between the subframe and the left front suspension arm.
19. Disconnect the electrical connector from the sensor.
20. Press the latches with pliers and release the rod retainer from the suspension arm.
21. Loosen the bolts and release the sensor from the mounting bracket.
Installation
22. Installation - reverse procedure.
Rear ride height sensor
Removal
23. The sensor is installed in the middle of the rear beam.
24. Disconnect the wiring connector from the sensor.
25. Loosen the bolt and disconnect the tie rod clamp from the beam.
26. Loosen the bolts and remove the sensor from the bracket.
Installation
27. Installation - reverse procedure.
Electronic control unit
Removal
28. The unit is installed on the right under the rear seat cushion.
29. Remove the rear seat cushion as described in chapter 11.
30. Open the sponge container and remove the unit. Disconnect the wiring connector from the unit and remove the unit from the vehicle.