The Mercedes-Benz ML63 AMG front turn signal bulb utilizes PY24WNA, 3457NA, or 3357NA sizes, while the rear turn signal bulb size measures 12496 or PY21W. The replacement chart covers 2007 through 2015 model years with corresponding bulb size specifications.
The year-by-year compatibility chart below provides a quick reference to verify the correct bulb size for your vehicle.
The PY24WNA is the most frequently specified front turn signal bulb across the Mercedes-Benz ML63 AMG range, covering the 2012-2015 model years when the vehicle is equipped with halogen capsule headlamps. It operates at 12V and 24W, uses a PGU20-4 base, and conforms to ANSI standards for the US and Canadian markets as an amber variant of the ECE PY24W.
The 3457NA is a dual-filament T25 wedge bulb rated at 12V with a 27W main filament and a 7W secondary filament. Its natural amber glass construction eliminates the need for a tinted lens or coating to produce the required amber signal color.
The 3357NA differs from the 3457NA in that it carries only a single filament rated at 27W, making the two bulbs non-interchangeable despite sharing the same T25 wedge form and natural amber glass. Substituting one for the other would result in either a missing secondary function or an incompatible circuit load.
The front turn signal on the Mercedes-Benz ML63 AMG shifted from the 3357NA in 2007 to the 3457NA for the 2008-2011 model years, representing a change from a single-filament to a dual-filament configuration.
The 2007 front turn signal specification is conditioned on the presence of HID headlamps, while the 2012-2015 specifications are conditioned on halogen capsule headlamps, indicating that headlamp technology directly influences the required turn signal bulb type.
The PY21W is an ECE-standard bulb with a BAU15s bayonet base, rated at 12V and 21W. Its standard is oriented toward European and worldwide markets, which distinguishes it from the ANSI-designated bulbs specified elsewhere in the ML63 AMG fitment data.
The rear turn signal of the Mercedes-Benz ML63 AMG used the PY21W for the 2008-2010 model years. Because the PY21W uses a BAU15s offset bayonet base, it is not physically interchangeable with bulbs using standard BA15s or wedge bases.
The 12496 is a Philips/Osram part number rather than an ANSI or ECE designation, placing it outside the standardized classification systems used by the other bulbs in these specifications. It is rated at 12V and is listed for the rear turn signal on the 2007 and 2011 model years.
The rear turn signal specification for the 2011 ML63 AMG reverts to the 12496 after three consecutive years of PY21W fitment, meaning the two bulb types are not interchangeable for that position despite occupying the same model line.