The Triumph TR7 uses a 194 bulb size for both front and rear side marker applications. The replacement chart covers 1975 to 1981 production years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The Triumph TR7 uses the 194 bulb for both front and rear side markers across all model years covered in the specifications, spanning 1975-1981.
The 194 is a miniature wedge bulb, classified under the T10 form factor, which refers to its tubular shape with a wedge-style base that requires no separate socket pins.
The 194 bulb operates at 12 volts with a power draw of 3.78 watts, placing it in the low-wattage range typical of marker and clearance lighting applications.
The 194 carries ANSI standardization recognized in both the United States and Canada, meaning the specification conforms to a defined performance and construction standard rather than being a proprietary designation.
Because the front and rear side marker positions on the Triumph TR7 share the same 194 bulb across all listed years, a single bulb type serves all four side marker sockets on the vehicle.
The wedge base of the 194 bulb is retained by friction within its socket rather than by a bayonet or screw mechanism, which is a defining characteristic of the T10 wedge form factor.