Interior light (Audi A4 B5)

Under the common diffuser (4) are located the incandescent lamps for the reading lights (1 and 3), as well as the interior light (2).



With the interior light removed (loosen the two screws on the middle reflector) on the reverse side, the switches (1 and 3) for the reading lights and the switch (2) for the interior light become accessible.



This door contact switch (1; here dismantled) is located only on the rear doors under the rubber attachment (2).



Left: On vehicles with vanity mirror lighting, the mirror insert (1) can be carefully pressed out of the sun visor frame. The microswitch (2) and both spotlights (3 and 4) for the mirror lighting will then be visible.



Right: In the instrument lighting, the socket and the incandescent lamp form one structural element. Here, the bulb is unscrewed. The number "1" shows the location of the bulb for the instrument lighting, the number "2" indicates 5 bulbs for lighting the on-board computer and the control device.

Functioning

In the Audi A4, the interior light is controlled by the central locking system: the central locking control unit influences the interior light as follows:

1. After the ignition key is removed, the interior light flashes.



2. When the car is opened, the interior lighting turns on.

3. When the ignition is turned on, as well as when the car is closed, the light turns off.

4. After the door is closed, the light remains on for about 30 seconds, but only if the ignition was turned on or the central lock was activated before this.

5. If the door remains open for more than 4 minutes, the interior light turns off.

Interior Lighting Lamps

1. Carefully press the flashlight diffuser out of the grooves and then remove the flashlight from the housing.

2. When installing, first insert the hooks on the back side into the cutout in the roof.

3. Remove the spotlight (10 W, length 41 mm) from the cartridge.

4. For a combination reading light, remove the glass-base bulb (5 W) from the socket.

Door contact switch for interior lighting

The front doors of the Audi A4 no longer have traditional door contact switches. Instead, a "door closed" contact is integrated into the central locking servomotor.

The situation is different with the rear doors: here, a traditional contact switch is installed in the door opening. It sends a direct signal about the door position to the central locking control unit, just like the contact of the front doors does. Malfunctions of this switch occur when:

• the switch push pin is jammed in the guide or is bent. Replace the switch;
• the wire connector has come off the switch. To make the connector hold better, bend it slightly and reinsert it;
• the contact surface of the switch with the mounting screw or the connector contacts are oxidized. Remove the oxide layer with sandpaper or a sharp screwdriver.

The door contact switch itself is screwed to the door post with only one Phillips-head screw. To remove it, remove the rubber cap, unscrew the screw, and pull out the switch.

Rear reading lights

Just like the front reading lights, the rear lights can be set to the interior light position by changing the switch position, so the rear of the car also benefits from interior light control. Replacing the bulbs:

1. Insert a screwdriver into the recess on the side of the lamp housing and gently pry the lamp out.

2. After replacing the bulb, reinsert the bulb housing, first with the side with the wire.

Makeup Mirror Lighting

1. Carefully press the mirror insert out of the sun visor frame.

2. Remove this incandescent lamp from the socket.

3. Insert the new bulb.

Trunk Light

Both lights for illuminating the boot are located on the left in the side trim of the boot, and also – somewhat hidden – in the crossbar under the rear window.

1. Open the hood.

2. Insert a screwdriver into the recess on the side of the lamp housing and carefully pry the lamp out.

3. After replacing the incandescent lamp (spotlight 5W, length 36mm) reinsert the lamp housing - first with the side with the wire.

Engine compartment light

1. Gently squeeze the lamp shade on the right and left and remove it.

2. The 10-watt bulb has a bayonet connection.