Toyota 4Runner Back Up Light Bulb Size

Additional Notes

• The Toyota 4Runner back up light uses the 921 bulb across the widest span of model years in these specifications, covering 2001-2024 for the standard position and appearing consistently in the outer back up light position from 2001-2019 as well.
• The 921 is a T15 wedge bulb rated at 12V and 16W under the ANSI standard, making it a lower-wattage option compared to the 7440 and 1156 bulbs also referenced in these specifications.
• The 7440 and 1156 bulbs are both rated at 12V and 21W, though they differ in base type. The 7440 uses a T20 wedge base, while the 1156 uses a BA15s bayonet base, meaning the two are not interchangeable despite sharing the same voltage and wattage rating.
• The 7443 bulb listed for the outer back up light on the 1996-1998 4Runner is a dual-filament T20 wedge bulb rated at 12V and 21W/5W, which distinguishes it from the single-filament 7440 despite sharing the same T20 form factor. These two bulbs are not direct substitutes for one another.
• The 1073 bulb, used on the 1984 4Runner, shares the BA15s bayonet base with the 1156 but operates at a lower wattage of 13W versus 21W, making it a distinct variant that is not a drop-in replacement for the 1156.
• The 2009 outer back up light position carries a production date qualifier, with the 921 bulb applying only to vehicles produced through August 2009, indicating a mid-year specification change for that model year.
• The 2000 model year outer back up light position reflects a mid-year transition, with the 7440 applying to vehicles produced through August 2000 and the 921 applying to those produced from August 2000 onward.
• The 1996 outer back up light specification for the 7443 bulb carries a production start date of November 1995, indicating that not all 1996 model year vehicles share this fitment.