Volvo VNL Back Up Light Bulb Size

The Volvo VNL back up light utilizes 3157 and 1156 bulb sizes for the rear illumination system. Data for the specified components covers the range from 2005 to 2015.

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
2014-2015	3157
2005-2013	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Dual-filament wedge bulb (T25). 12V, 27W/7W.	3157
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The 1156 bulb is the most frequently specified backup light bulb for the Volvo VNL, covering model years 2005-2013.
The 1156 operates on a single filament with a BA15s bayonet base, running at 12V and 21W. The BA15s base features a single contact pin, which physically prevents installation of dual-contact alternatives without modification.
The 3157 bulb is specified for the Volvo VNL in 2014-2015.
The 3157 is a dual-filament T25 wedge bulb rated at 12V with a 27W/7W output, where the two wattage values correspond to its high and low filaments respectively.
Both the 1156 and 3157 conform to ANSI standards applicable in the US and Canada, meaning their electrical and physical characteristics follow a defined industry specification rather than a proprietary one.
The 1156 and 3157 are not interchangeable. The 1156 uses a BA15s bayonet base while the 3157 uses a wedge-style base, making the two physically incompatible with the same socket.
Beyond the base type, the filament configuration also differs between the two bulbs. The 1156 carries a single filament, whereas the 3157 carries two, which affects how each bulb interfaces with the vehicle's wiring circuit.
A socket designed for the 3157 wedge base will not accept the BA15s pin base of the 1156, and the reverse is equally true, so year-specific fitment must be observed when sourcing a replacement.