Kia Sorento Turn Signal Bulb Size

Additional Notes

• The Kia Sorento front turn signal uses four distinct bulb types across its model years: PY21W, 2357NA, 2357, and the rear position adds P21W and 1156NA, making the Sorento one of the more varied fitment cases within a single nameplate.
• The 2357NA bulb is the most frequently specified type across both front and rear positions in the Kia Sorento, appearing in the front turn signal for the 2003-2006, 2018, 2020, and 2022 model years and in the rear for the 2020 model year.
• The 2357NA and 2357 bulbs share identical wattage ratings of 26.9W on the high filament and 8W on the low filament, as well as the same BAY15d dual-contact offset bayonet base, with the only distinction being that the 2357NA carries natural amber-tinted glass rather than clear glass.
• The PY21W is an ECE-standard single-filament amber bulb rated at 12V and 21W, fitted with a BAU15s bayonet base. Its offset pins distinguish it physically from the BA15s and BAY15d bases found on other bulbs in these specifications, making cross-substitution physically impossible without modification.
• The front turn signal of the Kia Sorento shifted from the ANSI-standard 2357NA to the ECE-standard PY21W for the 2021 and 2023-2024 model years, reflecting a base type change from BAY15d to BAU15s that prevents interchangeability between those fitments.
• The 1156NA is the dominant rear turn signal bulb across the Kia Sorento, specified for the 2003-2009 and 2018 model years. It is a single-filament ANSI bulb with a BA15s base rated at 12V and 21W, with natural amber glass providing the required amber output without a painted or coated lens.
• The P21W rear turn signal bulb, specified for the 2022-2023 Kia Sorento, shares the same BA15s bayonet base and 12V, 21W rating as the 1156NA, but it is an ECE-standard part with a clear glass envelope. The amber signal color in P21W applications is typically produced by the lens housing rather than the bulb itself.
• Because the 1156NA and P21W share the BA15s base and identical wattage, physical fitment between them is possible, but substituting a clear P21W for an amber 1156NA in a clear-lens housing would alter the output color and may not satisfy regulatory requirements for amber turn signals.
• The 2357 bulb, specified for the 2007-2009 front turn signal, uses a clear glass envelope with a BAY15d base. In applications requiring amber output, the amber color is produced by the lens rather than the bulb, which contrasts with the 2357NA variant that achieves amber output through its tinted glass.
• The dual-filament construction of the 2357 and 2357NA bulbs means they are capable of serving both a high-intensity and a low-intensity function within a single housing, a characteristic not shared by the single-filament PY21W, P21W, or 1156NA bulbs also present in these specifications.