The Saturn SC1 brake light uses 3157, 2458, and 2057 bulb sizes depending on the specific production period for the vehicle. Data for the bulb sizes covers the range from 1993 to 2002.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Saturn SC1 brake light circuit uses two bulb types across its production run: the 2057 for model years 1993-2000 and the 3157 for 2001-2002.
Both the 2057 and 3157 are dual-filament bulbs, meaning a single unit serves both the brake light and tail light functions within the same housing.
The 2057 bulb uses a BAY15d bayonet base and operates at 12V with a wattage of 26.9W on the high-filament circuit and 8W on the low-filament circuit.
The 3157 is a T25 wedge-type bulb operating at 12V with a 27W high filament and 7W low filament, and it is not interchangeable with the 2057 due to its different base type.
The 2057 is described as a brighter variant of the 1157, sharing the same BAY15d bayonet base, which means an 1157 may physically fit in a 2057 socket, though output levels would differ.
The Center High Mount Stop Light on the Saturn SC1 used the 921 bulb for model years 1997-2002, a single-filament T15 wedge bulb rated at 12V and 16W.
The 1996 SC1 Center High Mount Stop Light uses the PC175, a T10 miniature wedge bulb with a printed circuit board twist-lock socket, which is a fitment distinct from the 921 used in surrounding years and is not a standard socket type.
The 1995 SC1 Center High Mount Stop Light uses the PC168, also a T10 miniature wedge bulb with a printed circuit board twist-lock socket, sharing the same socket design as the PC175 but representing a separate ANSI designation.
The PC175 and PC168 twist-lock socket design is associated with instrument cluster applications, indicating the 1995-1996 Center High Mount Stop Light assemblies on the SC1 incorporated a non-conventional mounting interface.
All bulb types listed across the SC1 specifications conform to ANSI standards applicable in both the United States and Canada.