The Pontiac Fiero brake light requires a 2057 bulb size for proper installation and function within the rear lighting assembly. Data for the specified component covers the period from 1984 through 1988.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Pontiac Fiero uses the 2057 bulb for the brake light position across all five model years from 1984-1988, making it the sole bulb type for that application throughout the vehicle's entire production run.
The 2057 is a dual-filament bulb with a BAY15d bayonet base, operating at 12V with a wattage split of 26.9W on the high-filament circuit and 8W on the low-filament circuit, which allows it to serve both brake and tail light functions from a single unit.
The 2057 is a brighter variant of the 1157, sharing the same BAY15d bayonet base, which means the two types are physically interchangeable in many sockets, though the 2057 produces greater light output on the high-filament circuit.
The center high mount stop light on the Pontiac Fiero does not use a consistent bulb type across its available model years, with the 889 specified for 1986 and 1988 and the 906 specified for 1987.
The 889 is a single-filament halogen bulb with a PGJ13 base, rated at 12V and 37.5W, and its halogen construction distinguishes it technically from the non-halogen 906 used in the 1987 center high mount stop light position.
The 906 is a miniature wedge bulb in the T10 form factor, rated at 12V and 8W, and its wedge base design is physically incompatible with the PGJ13 base of the 889, meaning the two bulbs are not interchangeable despite occupying the same vehicle position across different model years.
All three bulb types listed in the Fiero brake specifications conform to ANSI standards applicable in both the United States and Canada, indicating standardized electrical and photometric performance requirements across the range.