The Mazda RX-7 front turn signal requires either a 3497 or 1157 bulb size, while the rear turn signal uses a 1156 or 1157 bulb size. The replacement chart covers 1979 to 1995 model 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 Mazda RX-7 front turn signal uses the 1157 bulb from 1979-1991, then transitions to the 3497 for the 1993-1995 model years.
The 1157 is a dual-filament bulb rated at 12V with a 21W main filament and a 5W secondary filament, mounted on a BAY15d bayonet base. The dual-pin offset base prevents incorrect installation by ensuring only one orientation fits the socket.
The 3497 is a single-filament bulb rated at 12V, 21W, and uses a BA15s bayonet base with a single locating pin. It is classified as a variant of the 1156 under ANSI standards.
Because the 1157 and 3497 differ in filament count and base type, BAY15d versus BA15s, the two bulbs are not interchangeable despite sharing a 21W rating at the primary filament.
The Mazda RX-7 rear turn signal uses the 1156 bulb from 1980-1995, a single-filament 12V, 21W bulb with a BA15s bayonet base.
The 1156 and 3497 share identical electrical ratings and the same BA15s base, making them physically and electrically interchangeable in rear turn signal sockets across the applicable model years.
The 1979 RX-7 rear turn signal uses the 1157 rather than the 1156 specified for all subsequent years, meaning the 1979 rear socket accepts a dual-filament BAY15d bulb rather than a single-filament BA15s unit.
All three bulb types listed, the 1156, 1157, and 3497, conform to ANSI standards recognized in both the United States and Canada, indicating standardized voltage, wattage, and base tolerances across those markets.