Mercury Villager Back Up Light Bulb Size

Additional Notes

• The Mercury Villager back up light specifications span three distinct bulb types across the 1993-2002 model years: the 2356, 3156, and 2456, all operating at 12V under the ANSI standard recognized in both the US and Canada.
• The 2356 bulb is a dual-filament type with a BAY15d bayonet base. Despite being a dual-filament bulb, it is specified here for a single-function application, meaning only one filament is in active use in this context.
• The BAY15d base of the 2356 differs from the BA15s base found on single-filament bulbs. These two base types are not interchangeable, as the BAY15d has offset pins to prevent incorrect installation of a dual-filament bulb in a single-filament socket.
• The 3156 is a single-filament wedge bulb rated at 27W. Unlike bayonet-base bulbs, wedge bulbs are held in place by friction rather than a locking mechanism, and the Mercury Villager (2001 and 1994) uses this type for its back up light.
• The 2456 is a festoon-style bulb, which is cylindrical in form and held between two end caps rather than inserted into a socket base. It appears across multiple non-consecutive model years of the Villager, including 1993, 1995, 1998, and 2000.
• For the 1963-1967 model years, the specifications reference the 1156 and 1141 bulbs, both of which share the BA15s single-contact bayonet base and a 12V, 21W rating. Their shared base type means physical fitment between the two is possible, though they are distinct ANSI part numbers.
• The 1962 Mercury Villager back up light uses the 1073 bulb, which also carries a BA15s bayonet base but is rated at 13W, making it a lower-wattage variant compared to the 1156 and 1141. Substituting a higher-wattage bulb in its place could affect the electrical load on that circuit.
• Across the 1993-2002 range, no single bulb type is used consistently throughout. The 2356 is the most frequently specified, covering the 1996-1997, 1999, and 2002 model years.
• The shift between bulb types across consecutive model years, such as from the 2456 in 2000 to the 3156 in 2001 and back to the 2356 in 2002, reflects changes in socket housing design between those model years, as each bulb type requires a physically different socket.
• All bulb types listed across the full specification range conform to ANSI standards applicable in both the US and Canada, indicating standardized electrical and physical tolerances for each part number.