The Nissan NX front turn signal requires a P21W or 1157 bulb size, while the rear turn signal uses a 1156 bulb size. The replacement chart covers 1991 to 1993 model 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 Nissan NX front turn signal uses different bulb types depending on the model year, with 1991-1992 specifying the 1157 and 1993 specifying the P21W.
The P21W follows the ECE standard used in Europe and worldwide markets, operating at 12V with a 21W single filament and a BA15s bayonet base.
The 1157 follows the ANSI standard used in the US and Canada, featuring a dual filament rated at 21W and 5W respectively, with a BAY15d bayonet base at 12V.
Although the P21W and 1157 share a similar wattage on their primary filament, they are not interchangeable due to different base types: the P21W uses a BA15s base while the 1157 uses a BAY15d base.
The BAY15d base on the 1157 includes offset pins that physically prevent it from seating into a BA15s socket, making cross-substitution between the 1157 and P21W impossible without modification.
The Nissan NX rear turn signal uses the 1156 across all three model years, 1991-1993, indicating no change in rear fitment over this period.
The 1156 is an ANSI-standard single-filament bulb rated at 12V and 21W, fitted with a BA15s bayonet base.
The 1156 and P21W share the same BA15s base type and the same 12V, 21W electrical rating, which means they are physically and electrically compatible in many applications.