Volvo S60 License Plate Bulb Size

Additional Notes

• The Volvo S60 license plate position uses two distinct bulb types across its model years: the DE3423 festoon bulb for 2007-2018 (excluding 2010) and the 12961 miniature wedge bulb for 2001-2006.
• The DE3423 is an ANSI-standardized festoon bulb recognized across the United States and Canada, operating at 12 volts with a 41mm length and end-cap contacts that seat into spring-loaded holders at each end of the bulb housing.
• The 12961 is a Philips part number designation for a T10 miniature wedge bulb, which uses a W2.1x9.5d base. This base type is a wedge-style connection that relies on the bulb's own glass envelope and wire leads to make contact, requiring no separate socket pins.
• The T10 wedge format of the 12961 is rated at 12 volts and 5 watts, placing it in the low-wattage range typical of license plate and courtesy lighting applications.
• The DE3423 festoon format and the 12961 wedge format are physically and electrically incompatible with each other. The socket designs differ fundamentally, as festoon holders accept cylindrical bulbs via end-cap tension, while wedge sockets grip the base of the bulb laterally.
• The Volvo S60 (2007-2018, excluding 2010) requires the DE3423, meaning a 12961 wedge bulb cannot be substituted in those model years without a socket adapter or housing modification.
• Festoon bulbs such as the DE3423 are identified by their length in millimeters, and the 41mm specification is a critical fitment factor, as festoon holders are length-specific and a bulb of a different length will not seat correctly.
• The W2.1x9.5d base designation on the 12961 describes a standardized wedge base where 2.1 refers to the wire contact width in millimeters and 9.5 refers to the base depth in millimeters, both of which determine socket compatibility.