The Audi Cabriolet brake light utilizes a P21/5W bulb size for illumination across all recorded vehicle versions within the provided data set. Information regarding the specific lighting component covers a time range from 1994 through 1998.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Audi Cabriolet uses the P21/5W bulb for its brake lights across the 1994-1998 model years.
The P21/5W is an ECE-standard dual-filament bulb rated at 12V with a 21W main filament and a 5W secondary filament, mounted on a BAY15d bayonet base.
The BAY15d base features offset pins, which physically prevents incorrect single-filament bulbs from being seated in the socket, as single-filament equivalents use a different pin configuration.
The dual-filament design of the P21/5W allows one filament to serve the brake function and the other to serve a secondary function such as a tail light within the same housing.
The Center High Mount Stop Light on the Audi Cabriolet uses the bulb size 70 across the 1994-1998 model years.
The 70 is an ANSI-standard miniature wedge bulb of the T5 form factor, rated at 12V and 1.4W, a significantly lower wattage than the main brake bulb.
The T5 wedge base relies on the bulb's glass envelope and wire leads to make contact with the socket, with no separate metal base component.
The P21/5W follows ECE regulations used in Europe and internationally, while the 70 follows ANSI standards used in the United States and Canada, reflecting different regional standardization bodies governing each bulb type.
The two bulb types used in the Audi Cabriolet's brake lighting system are not interchangeable, as they differ in base type, wattage, filament count, and governing standard.