Isuzu FSR Back Up Light Bulb Size

The Isuzu FSR back up light utilizes a single 1156 bulb size for the rear illumination system. Data for the specific component covers the range from 1996 through 2002.

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
1996-2002	1156 (Tilt Cab)

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 Isuzu FSR across the 1996-2002 model years, with all entries specifying the Tilt Cab configuration.
The 1156 is an ANSI-standard bulb recognized in both the United States and Canada, making it a widely available replacement in North American markets.
This bulb operates on a 12-volt electrical system and draws 21 watts, which is typical for incandescent reverse light applications.
The 1156 uses a single filament, meaning it serves one lighting function only, as opposed to dual-filament bulbs that handle two functions such as braking and running light simultaneously.
The BA15s bayonet base on the 1156 features a single locating pin on the base collar, which distinguishes it from the BA15d base used on dual-filament variants such as the 1157.
The BA15s base design requires a quarter-turn insertion into the socket, a fitment method that differs from wedge-base bulbs, which are not interchangeable with bayonet-mount sockets.
Because the 1156 and the dual-filament 1157 share the same BA15 bayonet shell size, there is a physical risk of inserting a 1157 into a 1156 socket; however, the 1157 has two locating pins and will not seat correctly in a single-pin socket, providing a mechanical safeguard against incorrect installation.
All seven model years in the specifications carry the Tilt Cab designation, indicating that this bulb size applies specifically to that cab style of the FSR.