Hyundai Elantra Daytime Running Light Bulb Size

The Hyundai Elantra daytime running light utilizes bulb size P21/5W or 12961 depending on the specific version of the vehicle. Data for the bulb sizes covers the range from 2003 to 2020.

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
2019-2020	P21/5W (With Halogen Capsule Headlamps)
2003	12961

Bulb Specifications

Description	Bulb Size
ECE standard (Europe & worldwide). Dual-filament signalling bulb with BAY15d bayonet base. 12V, 21W/5W.	P21/5W
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961

Other Locations

Additional Notes

The Hyundai Elantra uses two distinct daytime running light bulb types across its model years: the P21/5W for 2019-2020 and the 12961 for 2003.
The P21/5W is an ECE-standard dual-filament bulb rated at 12V with a 21W primary filament and a 5W secondary filament, mounted on a BAY15d bayonet base.
The BAY15d base features offset pins, which physically prevents incorrect single-filament bulbs from being seated in its socket, making polarity and filament orientation a fixed constraint.
On the 2019-2020 Hyundai Elantra, the P21/5W fitment applies specifically to vehicles equipped with halogen capsule headlamps, meaning this specification is conditional on the headlamp type installed.
The 12961 is a Philips part number designating a T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W, operating as a single-filament light source.
The W2.1x9.5d wedge base of the 12961 is not interchangeable with the BAY15d bayonet base of the P21/5W, as the two base types are mechanically incompatible with each other's sockets.
The P21/5W and 12961 also differ substantially in wattage output, with the P21/5W capable of drawing up to 21W on its primary filament compared to the 12961's fixed 5W draw.