Mercury Cougar Back Up Light Bulb Size

The Mercury Cougar back up light utilizes 1156, P21W, 2356, 2456, 3156, and 1076 bulb sizes depending on the specific version of the vehicle. Available data for the specified components spans a range from 1967 through 2002.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1999-2002	1156
1996-1997	2356
1993-1995	2456
1992	3156
1991	2356
1990	2456
1989	3156
1983-1988	1156
1974-1980	1156
1972-1973	1076
1967-1971	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. 12V.	2356
ANSI standard (US & Canada). Festoon bulb, specialty application. 12V.	2456
ANSI standard (US & Canada). Single-filament wedge bulb (T25). 12V, 27W.	3156
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 8W.	1076

Other Locations

Additional Notes

The Mercury Cougar back up light specifications span model years 1967 through 2002, covering four distinct bulb types across that range: 1156, 1076, 2356, 2456, and 3156.
The 1156 is the most frequently specified bulb across the Mercury Cougar's production history, appearing in model years 1967-1971, 1974-1988, and 1999-2002. It is a single-filament bulb with a BA15s bayonet base rated at 12V and 21W.
The 2456 is a festoon-style bulb designated for specialty applications, operating at 12V. It is specified for the Mercury Cougar in 1990, and 1993-1995.
The 2356 is a dual-filament bulb with a BAY15d bayonet base rated at 12V. It is specified for 1991, 1996, and 1997 model years. Its dual-filament design makes it physically and electrically incompatible with single-filament sockets.
The 3156 is a single-filament wedge bulb of the T25 form factor, rated at 12V and 27W. It is specified for the 1989 and 1992 Mercury Cougar. At 27W, it draws more power than the 1156, and the two are not interchangeable despite both being single-filament types.
The 1076 is specified for the 1972-1973 Mercury Cougar. It shares the BA15s bayonet base with the 1156 but is rated at only 8W, making it a lower-wattage variant. The shared base type does not make the two bulbs interchangeable, as the wattage difference affects light output and circuit load.
The BA15s bayonet base found on the 1156 and 1076 features a single locating pin, while the BAY15d base of the 2356 uses two offset pins. This physical difference prevents cross-installation between those bulb families.
All bulb types specified for the Mercury Cougar conform to ANSI standards applicable in the United States and Canada, indicating standardized electrical and physical tolerances within each bulb designation.