The Buick Somerset front and rear side marker bulbs both utilize a 194 bulb size. The replacement chart covers 1986 to 1987 vehicle production years with corresponding bulb specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 194 bulb is the sole bulb type listed across all side marker positions for the Buick Somerset, covering both the 1986-1987 model years.
The 194 bulb follows the ANSI standard recognized in both the United States and Canada, classifying it as a regionally standardized automotive lamp.
It is a miniature wedge-style bulb, designated T10, which refers to its tubular glass envelope with a wedge base that seats directly into a socket without a separate metal base or locking pins.
The T10 wedge format is a common fitment in low-wattage automotive marker and courtesy light applications, where compact packaging is a design consideration.
The 194 operates at 12 volts, consistent with the standard electrical system voltage found in conventional passenger vehicles of that era.
Its rated wattage of 3.78W places it in the low-power category, typical of side marker lamps that serve a visibility and signaling function rather than primary illumination.
The same 194 bulb size is specified for both the front and rear side marker positions, indicating that the Somerset uses a single bulb type across all four side marker locations.
The wedge base design of the T10 means fitment is determined by socket compatibility rather than a bayonet or screw-type locking mechanism, and substitutions require matching both the base type and the physical envelope size to avoid socket interference.