Volvo C70 Turn Signal Bulb Size

Additional Notes

• The 3357NA bulb follows the ANSI standard used in the United States and Canada. It is a single-filament wedge bulb in the T25 form factor with natural amber glass, rated at 12V and 27W. The Volvo C70 uses this type across the front turn signal position for the 1998 and 2001-2004 model years, as well as the 1998 front inner turn signal.
• The 3457NA differs from the 3357NA in that it carries a dual-filament design, operating at 27W on the primary filament and 7W on the secondary. Both share the T25 wedge form factor, natural amber glass, and 12V rating. The C70 uses the 3457NA exclusively in the front inner turn signal position for the 2001-2004 model years.
• Because the 3357NA and 3457NA share the same T25 wedge base and physical housing, they are physically interchangeable in the socket. However, the 3457NA carries a second filament that the 3357NA does not, which means substituting one for the other may affect intended circuit behavior depending on how the vehicle's wiring is configured.
• The PY21W bulb follows the ECE standard common in European and worldwide markets. It uses a BAU15s offset bayonet base, rated at 12V and 21W with a single filament. The offset pin arrangement of the BAU15s base is not compatible with the standard BA15s base, making PY21W bulbs non-interchangeable with wedge-base ANSI types without an adapter.
• The Volvo C70 uses the PY21W in the rear turn signal for the 1998, 2002-2004, 2007-2008, and 2010 model years, and in the front turn signal for the 2007-2008 and 2010 model years, reflecting the European-market origins of the platform across those generations.
• The 12496 is a part number associated with Philips and Osram rather than an ANSI or ECE classification. It is rated at 12V and designated for specialty halogen applications. The C70 uses this bulb in the front turn signal for the 2006 and 2009 model years, and in the rear turn signal for the 2006, 2009, and 2011-2013 model years.
• The 12274NA carries a natural amber glass designation and an OEM-style part number rather than a standardized ANSI or ECE code. It is rated at 12V, and the Volvo C70 uses it solely in the front turn signal position for the 2011-2013 model years.
• The natural amber glass construction of the NA-suffix bulbs, such as the 3357NA, 3457NA, and 12274NA, produces amber light from a clear or lightly tinted lens housing. This differs from clear-glass bulbs of the same base type, which rely on an amber-colored lens to produce the required turn signal color.
• Across the front turn signal position, the Volvo C70 uses five distinct bulb types over its production span, reflecting changes between the first-generation and second-generation platforms. The 1998 and 2001-2004 model years use ANSI-standard wedge bulbs, while later years transition to ECE-standard and OEM-numbered types.
• The rear turn signal position on the C70 does not share a consistent bulb type with the front turn signal in any given model year. For example, the 2011-2013 model years use the 12274NA at the front and the 12496 at the rear, indicating that front and rear positions require separate verification before replacement.