Ram C/V Dome Light Bulb Size

The Ram C/V dome light uses a 578 bulb size for interior illumination. The replacement chart covers 2012 to 2015 vehicle production years with corresponding bulb specifications.

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
2012-2015	578

Bulb Specifications

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

Other Locations

Additional Notes

The Ram C/V uses the 578 bulb for the dome light across the 2012-2015 model years.
The 578 is an ANSI-standardized bulb type, meaning its specifications are governed by a formal industry standard recognized in both the United States and Canada.
The 578 is a festoon-style bulb, a cylindrical form factor that seats between two spring-loaded end caps rather than inserting into a socket with a base pin or bayonet fitting.
The bulb measures 41mm in length, which is the critical fitment figure for festoon bulbs, as the housing span between the two contact points must match this value for proper installation.
The 578 operates at 12 volts, consistent with the standard electrical system voltage found in conventional passenger vehicles.
The bulb carries a 12-watt power rating, placing it in the mid-range for interior festoon applications.