Ford F-250 Courtesy Bulb Size

The Ford F-250 courtesy light utilizes unique bulb sizes 168, 912, 561, 89, 90, 1445, 631, 1004, and 1003 depending on the specific production period. Available data covers the range from 1956 to 1999.

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
1999	168
1995-1998	912
1994	561
1993	89
1988-1992	912
1987	90
1986	912
1985	89
1981-1984	912
1980	1445
1969-1972	631
1964-1968	1004
1956	1003

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 4.9W.	168
ANSI standard (US & Canada). Wedge bulb (T15). Variant of 921. 12V, 12W.	912
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	561
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Lower wattage variant of 1156. 12V, 13W.	89
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 13W.	90
ANSI standard (US & Canada). Single-filament bulb with BA9s base. 12V, 2W.	1445
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. Variant of 1156. 12V, 21W.	631
ANSI standard (US & Canada). Dual-filament bulb with BAY15d bayonet base. Variant of 1157. 12V, 21/5W.	1004
ANSI standard (US & Canada). Single-filament bulb with BA15s bayonet base. 12V, 21W.	1003

Other Locations

Additional Notes

The 912 bulb is the most frequently specified courtesy bulb size across the Ford F-250 model years listed, appearing in 1981-1986, 1988-1992, and 1995-1998. It is a T15 wedge-type bulb rated at 12V and 12W, and it is a variant of the 921 bulb.
The 631 bulb, specified for the Ford F-250 in 1969-1972, is a single-filament bulb with a BA15s bayonet base rated at 12V and 21W. It is classified as a variant of the 1156 bulb type.
The 1004 bulb, used across 1964-1968, is notable for being the only dual-filament bulb in these specifications. It uses a BAY15d bayonet base and carries a 21/5W rating, meaning it operates two separate filaments at different wattages. It is a variant of the 1157 bulb.
The 168 bulb, specified for the 1999 model year, is a miniature T10 wedge-type bulb rated at 12V and 4.9W. At 4.9W, it draws considerably less power than the 912 wedge bulb used in the preceding model years.
The 561 bulb, specified for 1994, is a festoon-type bulb with a 44mm length and end-cap contacts rather than a bayonet or wedge base. It is rated at 12V and 12W, matching the wattage of the 912 wedge bulb used in adjacent years.
The 1445 bulb, specified for 1980, uses a BA9s base and is rated at only 2W, making it the lowest-wattage bulb in these specifications by a significant margin.
The bulbs 89 and 90, specified for 1985 and 1987 respectively, share the same BA15s bayonet base and 12V, 13W ratings. The 89 is described as a lower-wattage variant of the 1156, which distinguishes it from the 90 despite their otherwise identical electrical ratings.
The 1003 bulb, specified for 1956, is a single-filament bulb with a BA15s bayonet base rated at 12V and 21W. It shares its wattage rating with the 631 and 1004 bulbs used in later decades, though it differs in base type from the dual-filament 1004.
All bulb types listed in these specifications conform to ANSI standards applicable in both the United States and Canada, indicating a standardized North American fitment classification across all model years covered.
Fitment interchangeability warrants attention in several cases. The 912 and 921 are related variants, the 631 and 89 are both variants of the 1156 family yet carry different wattages, and the 1004 is a variant of the 1157. Substituting across these variant groups without accounting for wattage and base-type differences risks an incorrect fitment.