Chevrolet Cobalt Map Light Bulb Size

The Chevrolet Cobalt map light requires bulb sizes 192 and 12961 for the interior lighting system. Data for the specific components covers the range from 2005 to 2010.

The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.

Bulb Size by Year Range

Years	Bulb Size
2008-2010	192
2005-2007	12961

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Miniature wedge bulb (T10). 12V, 3W.	192
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961

Other Locations

Additional Notes

The Chevrolet Cobalt map light draws from two distinct bulb types across its production run: the 192 and the 12961, both sharing the T10 miniature wedge form factor but differing in wattage.
The 192 bulb is an ANSI-standardized type distributed across the US and Canadian markets, operating at 12 volts and 3 watts.
The 12961 is a Philips part number designation rather than an industry-wide standard, operating at 12 volts and 5 watts with a W2.1x9.5d base specification.
The W2.1x9.5d base on the 12961 refers to a wedge base with a 2.1mm wire contact width and a 9.5mm insertion depth, which is the defining physical characteristic of the T10 wedge family.
The Chevrolet Cobalt (2008-2010) uses the 192 bulb for the map light position.
The 2005-2007 model years use the 12961 bulb instead, representing a different wattage rating despite the shared T10 form factor.
Although both the 192 and 12961 are T10 wedge bulbs and are physically interchangeable in terms of socket fit, their wattage values differ by 2 watts, which is a relevant consideration for socket heat ratings and circuit load.
The 192 is a widely sourced ANSI-coded bulb, meaning it is produced by multiple manufacturers under the same standardized designation, whereas the 12961 is tied to Philips nomenclature.