Mazda CX-5 Turn Signal Bulb Size

Additional Notes

• The 7440NA is the most widely used bulb across the Mazda CX-5 turn signal specifications. It is a single-filament T20 wedge bulb rated at 12V and 21W, finished in natural amber glass, and it covers the rear turn signal position across all model years from 2013-2023.
• The natural amber glass coating on the 7440NA, 7444NA, 7443NA, 1034NA, and 1157NA bulbs produces an amber light output without relying on a colored lens. This is the defining characteristic of the "NA" suffix in each bulb designation.
• The 7444NA is a dual-filament T20 wedge bulb rated at 12V with a 21W primary filament and a 5W secondary filament. Its dual-filament design distinguishes it from the single-filament 7440NA, despite both sharing the same T20 wedge form factor.
• The front turn signal on the Mazda CX-5 used the 7444NA from 2017-2020, then transitioned to the 7440NA for 2021-2023. The shift from a dual-filament to a single-filament bulb in the front position reflects a change in how the front signal circuit was configured between those generations.
• The T20 wedge base is shared by the 7440NA, 7444NA, and 7443NA. Although these bulbs share the same base type, their filament configurations differ, and substituting a single-filament bulb where a dual-filament bulb is specified, or vice versa, would result in incorrect circuit behavior.
• The 2016 Mazda CX-5 front turn signal has two distinct fitments depending on headlamp type. Vehicles with halogen capsule headlamps use the 1034NA, while vehicles with LED headlamps use the 7443NA. These two bulbs use different base types and are not interchangeable with each other.
• The 1034NA uses a BAY15d bayonet base and is described as a variant of the 1157. Both the 1034NA and 1157NA share the BAY15d bayonet base and a 12V, 21W/5W dual-filament configuration, which sets them apart from the T20 wedge bulbs used in other model years.
• The 1157NA was the front turn signal bulb for the Mazda CX-5 from 2013-2015. Its BAY15d bayonet base is physically incompatible with the T20 wedge socket used in later model years, making cross-generation substitution between these bulb families not possible.
• The 7443NA, used in the 2016 front turn signal position on LED headlamp-equipped vehicles, shares its dual-filament 21W/5W rating with the 7444NA. Both are T20 wedge bulbs, though they carry different ANSI designations and are not confirmed as interchangeable within these specifications.
• All bulbs listed across both the front and rear turn signal positions conform to ANSI standards applicable to the US and Canadian markets, as indicated by the shared ANSI classification noted in each bulb description.