Subaru 1400 Dome Light Bulb Size

The Subaru 1400 dome light requires a bulb size of 257 for the interior lighting system. Data for the specified vehicle covers the range from 1973 to 1974.

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
1973-1974	257

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon or BA9s base instrument bulb. 12V, 2W.	257

Other Locations

Additional Notes

The 257 bulb is the sole dome light bulb type listed for the Subaru 1400, covering the 1973-1974 model years.
The 257 is an ANSI-standardized bulb recognized across the United States and Canada, operating at 12 volts and 2 watts.
At 2 watts, the 257 draws minimal current, which is typical for interior courtesy lighting where low heat output and low power consumption are priorities.
The 257 bulb is available in two base configurations: festoon and BA9s. A festoon bulb is a cylindrical lamp held in place by spring-loaded end caps, while a BA9s is a single-contact bayonet base fitting into a round socket.
Because the 257 supports two distinct base types, the physical socket configuration of the specific vehicle determines which base variant is the correct fitment.