Subaru BRZ Back Up Light Bulb Size

The Subaru BRZ back up light utilizes 921 and 1157 bulb sizes for illumination purposes. Available information covers a span of time starting in 2013 and ending in 2023.

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
2023	1157
2022	921
2013-2020	921

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V, 21W/5W.	1157
ANSI standard (US & Canada). Wedge bulb (T15). 12V, 16W.	921

Other Locations

Additional Notes

The 921 bulb is the back up light specification for the Subaru BRZ across the 2013-2022 model years, making it the predominant fitment across the vehicle's production run covered by these specifications.
The 921 is a T15 wedge-base bulb operating at 12V with a 16W output, conforming to ANSI standards applicable in both the United States and Canada.
The wedge base of the 921 requires no locking mechanism, as the bulb is held in place by friction within the socket, distinguishing it from bayonet-style fittings.
The 2023 Subaru BRZ departs from the 921 specification, instead requiring the 1157 bulb for the back up light position.
The 1157 is a dual-filament bulb with a BAY15d bayonet base, rated at 12V and carrying two wattage ratings of 21W and 5W, also conforming to ANSI standards for the US and Canadian markets.
The BAY15d bayonet base of the 1157 features two offset pins that lock the bulb into the socket upon rotation, a physical configuration incompatible with the wedge socket used by the 921.
Because the 921 and 1157 use entirely different base types, the two bulbs are not interchangeable, and substituting one for the other across model years is not supported by these specifications.