Volkswagen Jetta Map Light Bulb Size

Additional Notes

• The Volkswagen Jetta map light uses two distinct bulb types across its model years: the 12961, a miniature wedge bulb, and the 6411, a festoon bulb. Both operate at 12V and 5W.
• The 12961 is a Philips part number designation for a T10 wedge bulb with a W2.1x9.5d base. This base type features two contact points at the bottom of the wedge, which differs from the pin or bayonet configurations found in other miniature bulb families.
• The 6411 follows the ANSI standard used in the United States and Canada. It is a festoon-style bulb, meaning it is cylindrical with end caps rather than a base socket, and it measures 36mm in length with an SV8.5 base.
• Despite sharing the same voltage and wattage ratings, the 12961 and 6411 are not interchangeable. Their base types are physically incompatible, as the wedge socket and festoon holder are entirely different mounting systems.
• The Volkswagen Jetta (1995-1998) uses the 6411 festoon bulb exclusively for the map light position.
• The 1999 model year is the only year in these specifications where two bulb sizes are listed for the same position. Early production 1999 Jettas use the 6411, while late model 1999 units use the 12961, indicating a mid-year transition between the two bulb types.
• From 2000 onward, the 12961 wedge bulb is the sole map light specification across all listed model years through 2020.
• The T10 designation of the 12961 refers to the bulb's tubular envelope width, measured in eighths of an inch, placing it in a widely used size class common across many automotive interior lighting applications.
• The SV8.5 base of the 6411 is a festoon base standard where the number refers to the contact cap width in millimeters. This base type is typical for dome and map lights in European vehicle designs of that era.
• The 12961 wedge format is specified for the Volkswagen Jetta map light across a notably longer span of model years than the 6411, covering the 2000-2020 range within these specifications as well as the late production 1999 units.