Volkswagen Cabriolet front turn signal bulbs use a P21/5W size while rear turn signal bulbs use a P21W size. The replacement chart covers vehicle production spanning 1985 to 1993.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Volkswagen Cabriolet uses the P21/5W bulb for the front turn signal across all model years from 1985-1993.
The P21/5W is a dual-filament bulb rated at 12V with a 21W primary filament and a 5W secondary filament, making it suitable for applications that serve two lighting functions from a single housing.
The P21/5W uses a BAY15d bayonet base, which is an offset twin-pin fitting. The offset pin placement is a deliberate design feature that prevents incorrect installation by ensuring the bulb can only be seated in one orientation.
The rear turn signal on the Volkswagen Cabriolet uses the P21W bulb across all model years from 1985-1993.
The P21W is a single-filament bulb rated at 12V and 21W, dedicated solely to signalling rather than a combined function.
The P21W uses a BA15s bayonet base, which is a single-pin fitting. This base is not interchangeable with the BAY15d base used on the front turn signal P21/5W bulb, despite both sharing the same 15mm base width.
Both the P21/5W and P21W conform to ECE standards, meaning they are recognized for use in Europe and other markets that follow ECE lighting regulations.
Although the P21W and P21/5W share the same 21W output on their primary filaments, substituting one for the other is not possible due to the differing base types and filament configurations.