Lexus RC F Courtesy Bulb Size

The Lexus RC F courtesy light utilizes 194 and 168 bulb sizes for the interior lighting system. Data for the specific components covers the period from 2015 through 2022.

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
2021-2022	194
2018-2019	194
2015-2016	168

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W.	168

Other Locations

Additional Notes

The Lexus RC F uses two distinct bulb sizes for its courtesy lighting across its model years: the 194 and the 168, both of which are ANSI-standardized miniature wedge bulbs of the T10 form factor rated at 12 volts.
The 194 bulb is specified for the 2018-2019 and 2021-2022 model years, operating at 3.78 watts.
The 168 bulb is specified for the 2015-2016 model years, operating at a higher wattage of 4.9 watts.
Although the 194 and 168 share the same T10 wedge base and 12-volt rating, their wattage values differ, which means the two types are not electrically identical despite their physical interchangeability at the socket level.
The T10 wedge base is a tubular single-filament design that seats without a bayonet or screw mechanism, relying instead on the tension of the socket contacts to retain the bulb.
Both the 194 and 168 carry ANSI standardization applicable to the US and Canadian markets, meaning their electrical and physical characteristics conform to a defined industry specification rather than a proprietary one.
The wattage difference between the 194 (3.78W) and the 168 (4.9W) reflects a difference in filament resistance, which affects the amount of current drawn from the vehicle's electrical circuit during operation.
Substituting a 168 in place of a 194, or vice versa, in the Lexus RC F would result in a mismatch with the wattage specified for that model year's courtesy lighting circuit.