Dodge B350 Back Up Light Bulb Size

The Dodge B350 back up light utilizes 921, P21W, and 1156 bulb sizes depending on the specific version of the component. Data for the bulb sizes covers the range from 1981 to 1994.

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
1994	921
1981-1993	1156

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Wedge bulb (T15). 12V, 16W.	921
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1156

Other Locations

Additional Notes

The Dodge B350 back up light specifications cover model years 1981 through 1994.
The 1156 bulb is the back up light fitment for the Dodge B350 across model years 1981-1993.
The 1156 is a single-filament bulb rated at 12V and 21W, fitted with a BA15s bayonet base, and recognized under ANSI standards in both the US and Canada.
A BA15s bayonet base uses a single contact pin, which means it is not interchangeable with dual-pin bayonet bases such as the BA15d.
For the 1994 model year, the Dodge B350 back up light specification changed to the 921 bulb.
The 921 is a wedge-type bulb in the T15 form factor, rated at 12V and 16W, and also carries ANSI recognition for the US and Canadian markets.
A wedge base and a BA15s bayonet base are mechanically incompatible socket types, so the 1156 and 921 bulbs are not interchangeable despite both operating at 12V.
The 921 draws 16W compared to the 1156 at 21W, reflecting a difference in power consumption between the two bulb types used across the B350's production span.