Ford Fusion Map Light Bulb Size

Additional Notes

• The Ford Fusion uses two distinct map light bulb types across its front and rear positions, with the front and rear positions drawing from different bulb families throughout the 2006-2012 model years.
• The rear map light position across all 2006-2012 Ford Fusion model years takes the 578 bulb, a festoon-style unit with end-cap contacts measuring 41mm in length, rated at 12V and 12W.
• The 578 bulb operates at 12W, which is notably higher wattage than either front map light bulb used in the same vehicle, as both the 12961 and 6411 are rated at 5W.
• The front map light position on the Ford Fusion (2009-2012) takes the 12961, a Philips-designated miniature wedge bulb in the T10 form factor with a W2.1x9.5d base, rated at 12V and 5W.
• The 12961 also serves the front map light on the 2007 Ford Fusion, making it the front bulb for five of the seven model years covered in the specifications.
• The 2006 and 2008 Ford Fusion front map light positions take the 6411 instead of the 12961. The 6411 is an ANSI-standard festoon bulb with an SV8.5 base, 36mm in length, rated at 12V and 5W.
• Although the 12961 and 6411 share the same 12V, 5W electrical rating, they are not interchangeable. The 12961 is a wedge-base T10 bulb, while the 6411 uses a festoon form factor with an SV8.5 base, meaning the socket types differ between the two front map light configurations.
• The 578 and 6411 are both festoon-style bulbs, but they differ in length (41mm versus 36mm) and wattage (12W versus 5W), which means they are not interchangeable despite sharing a similar physical form.
• The 12961 is identified by a Philips part number rather than an ANSI standard designation, whereas the 578 and 6411 are both classified under ANSI standards applicable in the US and Canada.
• The front map light bulb specification for the Ford Fusion changed between the 2007 and 2008 model years, shifting from the 12961 wedge bulb to the 6411 festoon bulb, then returning to the 12961 for the 2009 model year.