Renault R17 Back Up Light Bulb Size

The Renault R17 back up light utilizes 1156 and P21W bulb sizes for illumination. Data for the specified components covers the period from 1972 through 1979.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
1972-1979	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The 1156 is the sole back up light bulb size listed for the Renault R17 across all model years covered by these specifications.
The R17 uses the 1156 bulb for its back up lights from 1972-1979.
The 1156 is an ANSI-standardized bulb type, meaning its physical and electrical characteristics conform to a defined North American specification used in the United States and Canada.
As a single-filament bulb, the 1156 serves one lighting function only, which in this context is the back up light circuit.
The 1156 operates on a 12-volt electrical system and draws 21 watts, figures consistent with standard automotive reverse lighting applications of that era.
The 1156 uses a BA15s bayonet base, a single-contact mount where the bulb is inserted and rotated to lock into place, as opposed to a screw or wedge base design.
The BA15s designation indicates a single-contact bayonet fitting with a 15mm base width, which distinguishes it from the dual-contact BA15d variant used in other automotive applications.
The 1156 and the 1157 are often visually similar, but the 1157 uses a BA15d dual-contact base and carries two filaments, making it electrically incompatible as a direct substitute in a single-filament socket.