Volvo 242 License Plate Bulb Size

The Volvo 242 license plate light uses bulb sizes DE3423, 257, and 57 depending on the specific version. Available data covers the range from 1975 to 1984.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1981-1984	DE3423
1980	257
1979	57
1975-1978	257

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V.	DE3423
ANSI standard (US & Canada). Festoon or BA9s base instrument bulb. 12V, 2W.	257
ANSI standard (US & Canada). Single-filament bulb with BA9s base. 12V, 1W.	57

Other Locations

Additional Notes

The Volvo 242 license plate bulb specifications span the 1975-1984 model years, covering three distinct bulb types across that range.
The DE3423 is a festoon-style bulb operating at 12 volts, measuring 41mm in length with end-cap contacts at each end. This contact style means the bulb is held under spring tension between two metal terminals rather than inserted into a socket with a base.
The DE3423 is specified for the Volvo 242 across the 1981-1984 model years, making it the most frequently listed bulb type in these specifications.
The 257 is also a 12-volt festoon or BA9s base instrument bulb rated at 2 watts. Its dual-format designation reflects that it may be fitted in either a festoon holder or a BA9s bayonet socket depending on the lamp housing design.
The 257 is specified for the 1975-1978 and 1980 model years of the 242, giving it the widest year coverage of any single bulb type in these specifications.
The 57 bulb is a single-filament type with a BA9s base, rated at 12 volts and 1 watt. At half the wattage of the 257, it produces less light output despite sharing the same BA9s base style.
The 57 and 257 share a BA9s base, which is a miniature bayonet fitting with a 9mm cap. Despite this physical similarity, the two bulbs are not interchangeable due to their differing wattage ratings.
The 1979 Volvo 242 is the only model year in these specifications to use the 57 bulb, setting it apart from all surrounding years, which use either the 257 or DE3423.
All three bulb types carry ANSI standardization applicable to the US and Canadian markets, indicating conformance to a defined set of electrical and physical tolerances recognized across those regions.
The transition from the 257 in 1980 to the DE3423 in 1981 represents a shift from a BA9s-compatible socket to a festoon-only end-cap fitting, meaning the lamp housing design changed between those model years and the bulbs are not interchangeable.