The Audi V8 Quattro front turn signal uses a P21/5W bulb size while the rear turn signal requires a P21W bulb size. The replacement chart covers 1990 through 1994 production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Audi V8 Quattro uses two distinct bulb types across its front and rear turn signal positions for the 1990-1994 model years.
The front turn signal on the Audi V8 Quattro takes a P21/5W bulb across all 1990-1994 model years.
The P21/5W is a 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 two offset pins, a design that prevents incorrect insertion and distinguishes it from single-filament bases.
The rear turn signal position uses a P21W bulb across all 1990-1994 model years.
The P21W is a single-filament bulb rated at 12V and 21W, mounted on a BA15s bayonet base, which carries a single locating pin.
Because the P21/5W and P21W share a similar physical profile but carry different base types, BAY15d and BA15s respectively, the two bulbs are not interchangeable between the front and rear positions.
Both the P21/5W and P21W conform to ECE standards, a regulatory framework recognized across Europe and numerous other markets worldwide.