Chevrolet HHR Dome Light Bulb Size

The Chevrolet HHR dome light requires bulb size 578 or 562 depending on the specific configuration of the vehicle. Data for the bulb sizes covers the range from 2006 to 2011.

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
2011	578
2006-2007	562

Bulb Specifications

Description	Bulb Size
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V, 12W.	578
ANSI standard (US & Canada). Festoon bulb, 44mm length, end-cap contacts. 12V, 12W.	562

Other Locations

Additional Notes

The Chevrolet HHR dome light uses festoon-type bulbs across its model years, a bulb format characterized by a cylindrical glass tube with metal end-cap contacts at each terminal rather than a base socket.
Both the 578 and 562 are ANSI-standardized bulbs recognized in the United States and Canada, meaning their electrical and physical specifications conform to a defined industry standard.
The 578 and 562 bulbs share identical electrical ratings of 12 volts and 12 watts, placing them in the same power class for automotive interior lighting.
Despite matching voltage and wattage, the 578 and 562 differ in physical length. The 578 measures 41mm while the 562 measures 44mm, a 3mm difference that affects fitment in the dome light housing.
The 2011 Chevrolet HHR takes the 578 bulb, while the 2006-2007 model years take the 562 bulb, indicating a specification change occurred at some point between the 2007 and 2011 model years.
Because the 578 and 562 differ in length, they are not directly interchangeable. Installing the incorrect length in a festoon socket risks poor contact, intermittent function, or failure to seat properly.
End-cap festoon bulbs rely on spring tension within the housing to maintain electrical contact at both ends. A bulb that is too short may not maintain consistent contact, while one that is too long may not fit within the housing at all.