The Lexus GS300 parking light requires bulb sizes 7444NA, 168, 1034NA, and 1157NA depending on the specific version of the vehicle. Available data for the bulb sizes covers the range from 1993 to 2019.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Lexus GS300 front parking light draws from three distinct bulb types across its model years: the 7444NA, 168, and 1034NA appear most frequently, with the 1157NA limited to a single model year.
The 168 bulb is the most widely used across the GS300 front parking light fitment, covering the 1998-2006 model years. It is a T10 miniature wedge bulb rated at 12V and 4.9W, making it a single-filament, low-wattage unit suited to parking light duty.
The 7444NA is a T20 dual-filament wedge bulb rated at 12V with a 21W high filament and a 5W low filament. Its natural amber glass produces an amber output without the use of a colored lens or separate amber coating.
For the 2018-2019 Lexus GS300, the 7444NA is specified for the front parking light regardless of headlamp configuration, as both the standard and LED headlamp variants share the same bulb size for this position.
The 1034NA, used in the 1994-1997 GS300, is described as a variant of the 1157 bulb. Both share the BAY15d bayonet base and a 12V, 21W/5W dual-filament rating, but the 1034NA features natural amber glass rather than a clear envelope.
The 1157NA, specified for the 1993 GS300, shares the same BAY15d bayonet base and 12V, 21W/5W electrical rating as the 1034NA. Despite their near-identical specifications, the two are listed as separate ANSI bulb designations and are not confirmed as interchangeable within these specifications.
The BAY15d bayonet base found on both the 1034NA and 1157NA features two offset pins at different heights, a design that prevents incorrect single-filament substitutes from being seated in a dual-filament socket.
The T10 wedge base of the 168 bulb and the T20 wedge base of the 7444NA are physically incompatible with each other and with the BAY15d bayonet base used in earlier GS300 model years, meaning bulbs from different eras of this fitment are not interchangeable.
All four bulb types in these specifications conform to ANSI standards applicable to the US and Canadian markets, indicating standardized electrical and physical tolerances across those regions.
The shift from the BAY15d-based 1034NA to the T10-based 168 between the 1997 and 1998 model years reflects a change in both base type and filament count, as the 168 is a single-filament bulb while the 1034NA carries two filaments.