Dodge B250 Back Up Light Bulb Size

The Dodge B250 back up light utilizes 921, 1156, and P21W bulb sizes depending on the specific version of the vehicle. Available information covers the range from 1981 through 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 1156 bulb is the back up light specification for the Dodge B250 across the 1981-1993 model years.
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-contact bayonet bases found on other bulb types.
For the 1994 model year, the Dodge B250 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 in the US and Canada.
A wedge base relies on the bulb's glass pinch to make electrical contact, making it physically incompatible with the BA15s bayonet socket used in earlier B250 model years.
The 921 operates at 16W, while the 1156 operates at 21W, reflecting a difference in power draw between the two bulb types used across this vehicle's production span.
Because the 921 and 1156 use different base types, a 1994 B250 socket does not accept the 1156 specified for 1981-1993 models, and vice versa.