Hyundai Elantra GT Map Light Bulb Size

Additional Notes

• The Hyundai Elantra GT map light uses two distinct bulb types across its model years: the 904 and the DE3175, both of which conform to ANSI standards applicable in the United States and Canada.
• The DE3175 is a festoon-style bulb with a 31mm length and end-cap contacts, operating at 12 volts. It serves as the map light bulb for the Hyundai Elantra GT across the 2013-2018 model years.
• The 904 is a miniature wedge bulb in the T10 form factor, rated at 12 volts and 8 watts. It applies to the 2019 Elantra GT, but only for vehicles produced from March 21, 2017 onward.
• The festoon and wedge bulb formats are physically and electrically incompatible with each other. The DE3175 uses end-cap contacts seated into a cylindrical housing, while the 904 uses a wedge-style base inserted into a socket, making the two non-interchangeable.
• The 2019 model year carries a production date qualifier, meaning not all 2019 Elantra GT vehicles share the same map light bulb type. Units produced before March 21, 2017 fall outside the scope of the 904 specification listed here.
• The T10 designation of the 904 bulb refers to a tubular bulb with a width of approximately 10 thirty-seconds of an inch, a standard sizing classification used across the automotive lighting industry.
• Festoon bulbs such as the DE3175 are held in place by spring tension between two end contacts rather than a socket, a mounting method common in interior dome and map light applications.