Ram 1500 Map Light Bulb Size

The Ram 1500 map light utilizes bulb sizes 12961, 212-2, and 578 depending on the specific version of the vehicle. Available information covers a span of time starting from 2011 through 2024.

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
2024	12961
2023	212-2
2021	212-2
2013-2020	578
2011-2012	212-2

Bulb Specifications

Description	Bulb Size
Philips part number. Miniature wedge bulb (T10) with W2.1x9.5d base. 12V, 5W.	12961
ANSI standard (US & Canada). Festoon bulb, 41mm length, SV8.5 base. 12V, 12W.	212-2
ANSI standard (US & Canada). Festoon bulb, 41mm length, end-cap contacts. 12V, 12W.	578

Other Locations

Additional Notes

The bulb type 578 is the most frequently specified map light bulb across the Ram 1500 model years listed, covering 2013-2020.
The 578 is an ANSI-standard festoon bulb with a 41mm length, end-cap contacts, and a 12V, 12W electrical rating.
The 212-2 is also an ANSI-standard festoon bulb rated at 12V and 12W with a 41mm length, but it uses an SV8.5 base rather than end-cap contacts, making it a distinct fitment from the 578 despite sharing the same voltage, wattage, and body length.
The 212-2 is specified for the Ram 1500 in 2011-2012 and again in 2021 and 2023, while the 578 covers the intervening years, indicating that the two non-interchangeable festoon types alternate across the model's production span.
The 2024 Ram 1500 map light specification shifts entirely to the 12961, a miniature wedge-type bulb (T10) with a W2.1x9.5d base rated at 12V and 5W, which is a lower wattage than either festoon type used in prior years.
Because the 12961 uses a wedge base and the 578 and 212-2 use festoon-style bases, these three bulb types are not interchangeable with one another regardless of shared voltage ratings.
The 12961 designation is a Philips part number rather than an ANSI industry standard, which distinguishes it from the 578 and 212-2 designations used across all other listed years.