Volkswagen Cabrio front turn signal bulbs utilize 3457NA, 3357NA, or PY21W bulb sizes, while rear turn signal bulbs require P21W size. The replacement chart covers 1995 through 2002 model years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Volkswagen Cabrio front turn signal uses different bulb types depending on the model year, with P21/5W specified for 1995-1998, PY21W or 3457NA for 1999, 3357NA for 2000, and 3457NA for 2001-2002.
The 3457NA and 3357NA bulbs follow the ANSI standard used in the United States and Canada, while the P21/5W, PY21W, and P21W bulbs follow the ECE standard used in Europe and worldwide.
The 3457NA is a dual-filament wedge bulb in the T25 form factor, rated at 12V with a 27W main filament and a 7W secondary filament, and features natural amber glass that produces a colored output without a separate amber lens.
The 3357NA shares the same T25 wedge form factor and natural amber glass as the 3457NA but carries only a single filament rated at 27W, making the two bulbs non-interchangeable despite their physical similarities.
The P21/5W uses a BAY15d bayonet base and operates as a dual-filament bulb at 21W and 5W, a base type that is not compatible with the single-filament BA15s base found on the P21W.
The PY21W uses a BAU15s bayonet base, which is offset from the standard BA15s alignment, a design that prevents accidental installation of a clear P21W in a position requiring an amber signal output.
The 1999 Volkswagen Cabrio front turn signal has two separate specifications: the 3457NA applies to late models equipped with four headlamps, while the PY21W applies to a different configuration, indicating a mid-year production change.
The rear turn signal on the Volkswagen Cabrio uses the P21W across all model years from 1995-2002, a single-filament ECE bulb with a BA15s bayonet base rated at 12V and 21W.
Because the front turn signal transitions from ECE-standard bayonet bases in earlier years to ANSI-standard wedge bases in later years, the socket type in the housing differs between these production periods and the bulb types are not interchangeable across them.
The natural amber glass of the 3457NA and 3357NA wedge bulbs serves the same functional purpose as the inherently amber construction of the PY21W, producing a compliant amber signal output at the lens.