Mazda 3 Dome Light Bulb Size

The Mazda 3 dome light uses a DE3175 bulb size for interior illumination. The replacement chart covers vehicle production years spanning 2004 to 2009.

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
2004-2009	DE3175

Bulb Specifications

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

Other Locations

Additional Notes

The Mazda 3 uses the DE3175 bulb for the dome light across the 2004-2009 model years.
The DE3175 is an ANSI-standardized bulb type, meaning its physical and electrical specifications conform to a recognized North American standard used in the United States and Canada.
The DE3175 is a festoon-style bulb, which is a cylindrical lamp that makes electrical contact through metal caps at each end rather than through a base socket or pins.
The 31mm length of the DE3175 refers to the distance between its two end-cap contacts, which must match the span of the dome light housing's contact points for proper fitment.
The DE3175 operates at 12 volts, consistent with the standard electrical system voltage found in conventional passenger vehicles.
Because festoon bulbs rely on end-cap tension for contact, the 31mm length is a critical fitment factor. A bulb of a different length, such as the similar DE3021 at 28mm or the DE3022 at 34mm, would not seat correctly in the same housing.