The Mazda B2000 front turn signal requires a P21W or 1157 bulb size, while rear turn signal applications use either 1156 or 1157 bulb sizes. The replacement chart covers 1979 through 1987 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 Mazda B2000 front turn signal uses two distinct bulb types across its production span: the 1157 for model years 1979-1984 and the P21W for 1986-1987.
The 1157 is a dual-filament bulb rated at 12V with a 21W primary filament and a 5W secondary filament, operating on a BAY15d bayonet base under the ANSI standard used in the US and Canada.
The P21W is a single-filament bulb rated at 12V, 21W, using a BA15s bayonet base. It follows the ECE standard common in Europe and worldwide markets.
Although the P21W and the 1156 share the same BA15s bayonet base and the same 12V, 21W rating, they originate from different standardization systems, with the P21W governed by ECE regulations and the 1156 by ANSI standards.
The rear turn signal of the Mazda B2000 transitions from the dual-filament 1157 used in 1979-1984 to the single-filament 1156 used in 1986-1987, representing a reduction in filament count at the rear position for the later years.
The 1157 used in the front position for 1979-1984 features a BAY15d base, which has offset pins to prevent incorrect installation. This base is not interchangeable with the BA15s base found on the 1156 and P21W.
For 1986-1987, the front and rear turn signals use different bulb standards: the front uses the ECE-standard P21W while the rear uses the ANSI-standard 1156, despite both being single-filament 12V, 21W bulbs with BA15s bases.
For model years 1979-1984, both the front and rear turn signals of the Mazda B2000 use the same 1157 bulb, allowing a single bulb type to serve both positions during that period.