Honda Ridgeline Back Up Light Bulb Size

Additional Notes

• The Honda Ridgeline backup light specifications cover two distinct bulb sizes across the listed model years: the 7440 and the 921, both of which conform to ANSI standards applicable in the US and Canada.
• The 7440 is a single-filament wedge bulb in the T20 form factor, rated at 12V and 21W, and it fits the Honda Ridgeline for the 2017-2020 and 2023-2024 model years.
• The T20 form factor of the 7440 is physically larger than the T15 form factor of the 921, making the two bulbs non-interchangeable despite sharing the same wedge base style.
• The 921 is a wedge bulb in the T15 form factor, rated at 12V and 16W, and it fits the Honda Ridgeline for the 2006-2014 model years.
• The 7440 operates at 21W while the 921 operates at 16W, meaning the 7440 draws more power and produces greater output under the same 12V supply.
• Both bulbs use a wedge-style base, which requires no locking pins or bayonet turns for installation, as the base itself is held in place by tension within the socket.
• Because the two bulbs differ in both form factor and wattage, a 921 cannot serve as a direct replacement in a socket designed for a 7440, and vice versa.
• ANSI standardization means that any 7440 or 921 bulb from different manufacturers sharing the same designation is expected to conform to the same electrical and physical specifications.