Ford L800 Back Up Light Bulb Size

The Ford L800 back up light requires a bulb size of 1156 for the specific lighting component located at the rear of the vehicle. Data for the bulb size covers the range from 1980 to 1985.

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
1980-1985	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The Ford L800 uses the 1156 bulb for the back up light across the 1980-1985 model years.
The 1156 is an ANSI-standardized bulb type, meaning its physical and electrical specifications are governed by a recognized North American standard shared across the United States and Canada.
This bulb operates on a 12-volt electrical system and draws 21 watts, which is typical of incandescent automotive lighting designed for visibility rather than low power consumption.
The 1156 is a single-filament bulb, meaning it serves one lighting function only, which is consistent with its use in a dedicated back up light application.
The base type is BA15s, a bayonet-style mount with a single contact pin. The "s" in BA15s denotes a single contact at the base, distinguishing it from the dual-contact BA15d used in two-filament applications.
Because the 1156 uses a BA15s base, it is not interchangeable with visually similar bulbs such as the 1157, which uses a BA15d base and carries two filaments. Substituting one for the other is not compatible without socket modification.