Jeep Willys Map Light Bulb Size

The Jeep Willys map light requires a bulb size of 81 for the interior lighting assembly. Data for the specified component covers the period from 1953 through 1955.

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
1953-1955	81

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 8W.	81

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Additional Notes

The bulb type 81 is an ANSI-standardized single-filament bulb rated at 12 volts and 8 watts, fitted with a BA15s bayonet base. The BA15s designation indicates a single-contact bayonet cap with a 15mm base width.
The Jeep Willys uses the type 81 bulb for the map light across the 1953-1955 model years.
The BA15s base is a single-contact design, meaning it is not interchangeable with the BA15d base, which carries two contacts. Substituting one for the other is not possible without a socket adapter.
At 8 watts on a 12-volt circuit, the type 81 draws approximately 0.67 amperes, which is consistent with low-demand interior lighting applications such as map lights.