Acura ILX Side Marker Bulb Size

Acura ILX side marker bulbs use 12961 and 168 sizes for front positions, with 12961 and 7443 sizes for rear positions. The replacement bulb size chart covers 2013 through 2022 production years.

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

Front Side Marker

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

Years	US Type	EU Type	Shop
2021-2022	12961	12961	Check Price
2013-2018	168	W5W	Check Price

Rear Side Marker

If US Type and EU Type show the same value, a direct cross-reference for this bulb is not available or the data is insufficient.

Years	US Type	EU Type	Shop
2021-2022	12961	12961	Check Price
2013-2015	7443	W21/5W	Check Price

Bulb Specifications

Description	Type	Shop
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961	Check Price
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W.	168	Check Price
ECE standard (Europe & worldwide). Single-filament signalling bulb with W2.1x9.5d wedge base. 12V, 5W.	W5W	Check Price
ANSI standard (US & Canada). Dual-filament wedge bulb (T20). 12V, 21W/5W.	7443	Check Price

Other Locations

Additional Notes

The Acura ILX front side marker uses the 168 bulb for model years 2013-2018, then transitions to the 12961 for 2021-2022. Both are T10 miniature wedge bulbs operating at 12V, though the 168 is rated at 4.9W while the 12961 is rated at 5W.
The 12961 is a Philips part number rather than an ANSI industry standard designation. It uses a W2.1x9.5d base, which is the standard wedge base shared by T10 bulbs, and operates at 12V, 5W.
The 168 bulb follows the ANSI standard recognized in the United States and Canada. Its T10 wedge form factor makes it physically similar to the 12961, though the two are defined under different classification systems.
For the Acura ILX rear side marker, the 2013-2015 model years use the 7443, a dual-filament T20 wedge bulb rated at 12V with a 21W high filament and a 5W low filament. The 2021-2022 rear side marker position uses the 12961 instead, a single-filament T10 bulb. These two bulbs are not interchangeable due to differences in filament count, wattage, and physical size.
The 7443 is a T20 wedge bulb, which is physically larger than the T10 form factor used by both the 168 and the 12961. Substituting a T10 bulb in a T20 socket, or vice versa, would result in an improper fit.
The dual-filament design of the 7443 allows a single bulb to serve two lighting functions at different brightness levels, a characteristic absent in the single-filament 168 and 12961 bulbs.
The rear side marker position on the ILX has no listed specification for 2016-2018, while the front side marker position carries no listed specification for 2019-2020 across either position. These years are simply absent from the provided data for their respective positions.