Mazda Protege Dome Light Bulb Size

The Mazda Protege dome light utilizes bulb sizes DE3175, 194, and 168 depending on the specific version of the vehicle. Available data for the listed components covers the range from 1990 to 2003.

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
1995-2003	DE3175
1992-1994	194
1991	DE3175
1990	168

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 31mm length, end-cap contacts. 12V.	DE3175
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3.78W.	194
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W.	168

Other Locations

Additional Notes

The Mazda Protege dome light bulb specifications span model years 1990 through 2003, covering three distinct bulb sizes across that range.
The DE3175 is the most frequently specified bulb in these records, appearing in the Mazda Protege across 1991 and 1995-2003.
The DE3175 is a festoon-type bulb, meaning it seats horizontally between two end-cap contacts rather than inserting into a socket. It measures 31mm in length and operates at 12 volts.
The 194 bulb is specified for the 1992-1994 Protege dome light. It is a T10 miniature wedge bulb rated at 12V and 3.78W.
The 168 bulb is specified for the 1990 Protege. Like the 194, it is a T10 miniature wedge type, but it carries a higher wattage rating of 4.9W at 12V.
Although the 194 and 168 share the same T10 wedge form factor, their wattage ratings differ. The two are not electrically identical, and substituting one for the other may affect circuit load.
The festoon DE3175 and the T10 wedge bulbs (194 and 168) use fundamentally different contact designs and are not interchangeable with one another.
All three bulb sizes listed in these specifications conform to ANSI standards applicable in the United States and Canada.
The 1991 Protege uses the DE3175 festoon bulb, while the immediately following 1992-1994 model years use the 194 wedge bulb, indicating a socket type change between those production periods.
From 1995 onward through the final 2003 model year covered in these specifications, the dome light fitment for the Protege returned to and remained consistent with the DE3175 festoon bulb.