The Mercury Capri brake light utilizes a 1157 bulb size for the specific lighting component located at the rear of the vehicle. Available data covers the range from 1970 through 1994 for the specified automotive application.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Mercury Capri uses the 1157 bulb for brake lighting across all model years represented in the specifications, spanning 1970-1986 and 1991-1994.
The 1157 is a dual-filament bulb rated at 12V with a 21W high filament and a 5W low filament, mounted on a BAY15d bayonet base, which allows it to serve both brake and tail light functions from a single unit.
The BAY15d bayonet base on the 1157 features two offset pins, a design that prevents incorrect installation by ensuring the bulb can only be seated in one orientation.
For the Center High Mount Stop Light, the Mercury Capri (1991-1994) takes a 922 wedge bulb rated at 12V and 16W.
The 1986 Mercury Capri Center High Mount Stop Light uses the 912 bulb rather than the 922, rated at 12V and 12W.
Both the 922 and 912 are T15 wedge bulbs, meaning they share the same physical form factor, but their wattage ratings differ at 16W and 12W respectively, making them non-equivalent replacements despite their similar appearance.
The 912 is classified as a variant of the 921 bulb, a designation that reflects a close electrical relationship between the two types within the T15 wedge family.
All bulb sizes listed across the specifications conform to ANSI standards applicable in both the United States and Canada.
The shift from the 912 in 1986 to the 922 in 1991-1994 for the Center High Mount Stop Light position reflects a wattage increase of 4W at that lamp location between those model years.
The 1157 and the 922/912 wedge bulbs are not interchangeable, as they differ in base type, filament count, and wattage, serving structurally distinct lamp positions on the vehicle.