Kia K5 Turn Signal Bulb Size

Additional Notes

• The PY21W is an ECE-standard single-filament amber bulb operating at 12V and 21W, fitted with a BAU15s bayonet base. The amber tint is built into the glass envelope itself, which allows it to produce the legally required amber signal color without relying on a colored lens.
• The P21W shares the same ECE standard, 12V rating, and 21W output as the PY21W, but it is a clear single-filament bulb fitted with a BA15s bayonet base rather than a BAU15s base.
• The BAU15s base used by the PY21W and the BA15s base used by the P21W are physically distinct. The offset pins on the BAU15s base are positioned at different angles than those on the BA15s, meaning the two bulb types are not interchangeable despite their otherwise similar electrical ratings.
• The Kia K5 rear turn signal uses the PY21W for the 2023-2024 model years and the P21W for the 2021 model year, representing a base-type difference across the production run that has a direct bearing on replacement part selection.