The Renault R12 front and rear turn signal bulbs both utilize a 1157 bulb size for proper operation. The replacement chart covers 1971 through 1977 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 Renault R12 uses the 1157 bulb for both its front and rear turn signals across all listed model years from 1971-1977.
The 1157 is a dual-filament bulb, meaning it contains two separate filaments within a single glass envelope, allowing it to serve two distinct lighting functions at different wattages.
It operates on a 12-volt electrical system and draws 21 watts on its primary filament and 5 watts on its secondary filament.
The 1157 uses a BAY15d bayonet base, which features two offset pins at different heights to ensure the bulb is inserted in the correct rotational orientation, preventing filament misalignment.
The 1157 is an ANSI-standardized bulb type recognized across the United States and Canada, placing it within a widely distributed specification category.
The uniform use of the 1157 across both the front and rear turn signal positions on the Renault R12 means a single bulb type serves all four turn signal housings on the vehicle.
Because the BAY15d base has asymmetrically placed pins, substituting a bulb with a single-pin bayonet base or a symmetrical dual-pin base would result in an incompatible fit.
A replacement bulb must match both the BAY15d base type and the 21W/5W dual-filament wattage rating to function correctly within the R12's turn signal circuit.