Chrysler Pacifica Dome Light Bulb Size

Additional Notes

• The 578 bulb is the sole dome light bulb size listed for the Chrysler Pacifica across all model years in the specifications.
• The 578 is a festoon-type bulb, meaning it is cylindrical in shape and makes electrical contact through metal caps at each end rather than through a base socket.
• Festoon bulbs are held in place by spring-loaded clips in the fixture, with the end caps pressing against the contacts to complete the circuit.
• The 578 bulb has a length of 41mm, which is a critical fitment factor, as festoon bulbs must match the span between the fixture's contact clips.
• It operates at 12 volts and 12 watts, which is consistent with standard automotive electrical systems.
• The 578 designation follows ANSI standards recognized in both the United States and Canada, indicating a standardized specification rather than a proprietary part number.
• The 2004-2008 Pacifica model years all share the same 578 bulb size for the dome light, as does the 2021 model year.
• Because the 578 is an ANSI-standardized bulb, it is produced by multiple manufacturers, though any replacement must match the 41mm length and end-cap contact configuration to fit correctly.
• A festoon bulb of a different length, even if rated at the same voltage and wattage, would not seat properly in a fixture designed for the 41mm 578 specification.
• LED replacements for the 578 are available in the aftermarket, provided they conform to the 41mm festoon form factor and 12-volt operating requirement.