Mercury Capri front and rear side marker bulbs utilize 194 and 1157 bulb sizes, with the front requiring the 194 size and the rear accommodating either 194 or 1157 configurations. The replacement chart covers vehicle production spanning 1970 to 1994, detailing bulb size specifications across the model's manufacturing period.
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 194 bulb as the dominant side marker bulb type across its front and rear positions, spanning model years 1970-1994.
The 194 is a T10 miniature wedge bulb rated at 12 volts and 3.78 watts, standardized under ANSI specifications for use in the United States and Canada.
The 1157 is a dual-filament bulb with a BAY15d bayonet base, rated at 12 volts with a 21W/5W filament configuration, also standardized under ANSI specifications for the US and Canada.
The BAY15d bayonet base of the 1157 features offset pins, which physically prevents it from being inserted into sockets designed for single-filament bayonet bulbs, making cross-substitution with non-equivalent types mechanically restricted.
The Mercury Capri rear side marker position uses the 1157 bulb for the 1982-1984 model years, in contrast to the 194 used in all other listed rear side marker years.
The front side marker position on the Mercury Capri uses the 194 bulb exclusively across all listed model years, with no variation in bulb type.
The 1157 and 194 bulbs are not interchangeable. The 1157 uses a BAY15d bayonet base while the 194 uses a wedge base, and their wattage ratings differ substantially, making socket and electrical compatibility mutually exclusive between the two types.
The wattage difference between the 194 (3.78W) and the 1157 (21W/5W) reflects a fundamental difference in function, as the higher-wattage 1157 is typically associated with combined stop and tail light duties rather than low-draw marker applications.