Smart Fortwo Map Light Bulb Size

Additional Notes

• The Smart Fortwo uses the 12961 bulb for the map light across all listed model years from 2011 to 2018, making it the sole bulb type specified for this application.
• The 12961 is a Philips part number designating a miniature wedge bulb in the T10 form factor with a W2.1x9.5d base, rated at 12 volts and 5 watts.
• The T10 designation refers to a tubular bulb approximately 10mm wide, commonly found in low-current interior lighting roles such as map, dome, and courtesy lights.
• The W2.1x9.5d base is a wedge-type base, meaning the bulb is held in its socket by the tension of the base itself rather than by a bayonet or screw mechanism.
• At 5 watts on a 12-volt circuit, the 12961 draws approximately 0.42 amperes, consistent with the low power demands typical of interior reading and map light applications.
• For the 2011-2014 Smart Fortwo, the specifications note both Front and Center map light positions, both of which use the 12961 bulb.
• The W2.1x9.5d base is a specific wedge standard, and substituting a bulb with a physically different wedge base width or pin configuration would result in an improper fit even if the voltage and wattage ratings matched.
• Because the 12961 is a Philips-assigned part number, equivalent bulbs from other manufacturers are cross-referenced to the same T10 W2.1x9.5d 12V 5W specification rather than to the Philips number itself.