The Mitsubishi Outlander tail light utilizes 7443, 7440, and P21/5W bulb sizes depending on the specific version of the vehicle. Data for the bulb sizes covers the range from 2003 to 2015.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The 7443 is the most frequently specified bulb across the Mitsubishi Outlander tail light data, appearing in both the inner and outer tail light positions across multiple model years. It follows the ANSI standard used in the US and Canada, uses a T20 wedge base, and operates at 12V with a dual-filament output of 21W and 5W.
The dual-filament design of the 7443 allows a single bulb to serve two lighting functions simultaneously, typically combining a brighter stop light output with a dimmer running light output within one housing.
The 7440 shares the same T20 wedge form factor as the 7443 but carries only a single filament rated at 21W. The Mitsubishi Outlander (2005-2006) outer tail light position uses the 7440, while the 7443 appears in that same position for 2003-2004, making the two bulbs non-interchangeable despite their physical similarity.
Substituting a 7440 for a 7443, or vice versa, would result in either a missing filament or an incorrect wiring connection, as the single-filament and dual-filament versions are electrically distinct even though they share the T20 wedge housing.
The 12961 is a Philips-designated part number for a T10 miniature wedge bulb with a W2.1x9.5d base, rated at 12V and 5W. It is specified for the inner tail light position on the 2005-2006 Outlander.
The T10 form factor of the 12961 is physically smaller than the T20 used by the 7443 and 7440, meaning bulbs from those two groups are not interchangeable with the inner tail light position on the 2005-2006 Outlander.
The P21/5W follows the ECE standard used in Europe and worldwide markets, uses a BAY15d bayonet base, and is rated at 12V with a dual-filament output of 21W and 5W. Its bayonet base is mechanically incompatible with the wedge sockets used by the 7443 and 7440.
The 2015 Outlander outer tail light specification notes a P21/5W bulb with the qualifier "With Halogen Capsule Headlamps," indicating that this fitment applies to a specific headlamp configuration rather than all 2015 Outlander variants.
The 7443 and P21/5W share identical wattage ratings of 21W and 5W across their respective filaments, but their base types differ entirely. The 7443 uses a wedge base while the P21/5W uses a BAY15d bayonet base, making them physically non-interchangeable regardless of their matching electrical ratings.
The outer tail light position on the Mitsubishi Outlander reflects a shift across model years, with the 7443 specified for 2003-2004, the 7440 for 2005-2006, and the P21/5W for 2014-2015, representing distinct and non-interchangeable bulb types across those periods.