How to replace turn signal bulb for Audi A4 (B5)

Car turn signals or blinkers are twinkling lights, situated at front and rear of the vehicle. The appearance of these lights are controlled by the driver to alert others, that the car is about to stop/start moving or change movement direction. It's essential turn signals are in operation at the right time, thus forewarning other drivers and keeping the road safe. That is the reason, all turn indicators should be operating without problems. The most common cause of a faulty turn indicator is an obsolete bulb, which does not require examining the blinker itself to find out: every time turn signal is active, flickering rate of a corresponding indicator in dashboard will be increased, if there is a non-working bulb on a specific side.