The Ford Tempo brake light uses 3157, 2458, 2357, and 1157 bulb sizes depending on the specific version of the vehicle. Available data for the lighting components covers the range from 1984 to 1991.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Ford Tempo brake light specifications reference three distinct bulb types across the 1984-1991 model years: the 1157, 2357, and 3157. All three are dual-filament bulbs operating at 12V, meaning each carries two separate filaments serving both the brake and tail light functions within a single housing.
The 1157 and 2357 both use a BAY15d bayonet base, which is a double-contact offset-pin base. This shared base type means the two bulbs are physically interchangeable in terms of fitment, though their wattage ratings differ.
The 2357 operates at 26.9W/8W, while the 1157 operates at 21W/5W. The 2357 is the higher-output variant of the 1157, producing a brighter brake light signal at its high-filament wattage.
The Ford Tempo (1984-1985) uses the 1157, the 1986-1988 models use the 2357, and the 1989-1991 models use the 3157 for the standard brake light position.
The 3157 is a T25 wedge-base bulb rather than a bayonet-base bulb, operating at 27W/7W. Its wedge base makes it physically incompatible with the BAY15d socket used by the 1157 and 2357, despite similar wattage characteristics.
The Center High Mount Stop Light (CHMSL) specifications cover the 1986-1994 model years and reference two bulb types: the 912 and the 921. Both are single-filament T15 wedge bulbs operating at 12V.
The 912 is rated at 12W and the 921 at 16W. The 912 is a lower-wattage variant of the 921, and while both share the T15 wedge form factor, substituting one for the other would result in a difference in light output.
The Ford Tempo CHMSL used the 912 from 1986-1988 and transitioned to the 921 from 1989-1994, representing a shift to the higher-wattage T15 variant for that position.
All five bulb types listed across both positions conform to ANSI standards applicable in the United States and Canada, indicating standardized electrical and physical specifications within those markets.
The 921 and 912 are single-filament bulbs, suited only for a dedicated stop light function, whereas the 1157, 2357, and 3157 dual-filament bulbs serve a combined stop and tail light role from a single socket.