Subaru Outback Map Light Bulb Size

The Subaru Outback map light requires a DE3175 bulb size for proper installation within the interior overhead lighting housing. Available data covers a span of time starting from 2008 through 2021.

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
2021	DE3175
2008-2019	DE3175

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 31mm length, end-cap contacts. 12V.	DE3175

Other Locations

Additional Notes

The Subaru Outback map light uses the DE3175 bulb across the 2008-2021 model years covered in these specifications.
The DE3175 is a festoon-type bulb, meaning it is cylindrical in shape and makes electrical contact through metal caps at each end rather than through a base socket.
Festoon bulbs are held in place by spring-loaded clips that press against the end caps, which is the standard mounting method for map and dome light applications.
The DE3175 has a nominal length of 31mm, which is the critical fitment factor for festoon bulbs, as the spring clips must compress correctly against the end caps to maintain a stable connection.
The bulb operates on a 12V circuit, consistent with standard automotive electrical systems.
The DE3175 designation follows ANSI standards recognized in both the United States and Canada, indicating a standardized specification rather than a proprietary part number.
Because the DE3175 is an ANSI-standardized festoon bulb, aftermarket and LED replacement bulbs sold under the same designation are generally produced to the same 31mm length and end-cap contact configuration.
When substituting an LED replacement for the DE3175 in the Subaru Outback, the physical length of the LED unit must match the 31mm festoon specification to seat correctly in the factory clip holders.