The Mercedes-Benz G55 AMG front inner turn signal uses a 1156NA or PY21W bulb size, while front and rear turn signals utilize PY21W and 12496 bulb sizes respectively. The replacement chart covers 2003 to 2011 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 1156NA and PY21W bulb types are the most frequently specified turn signal bulbs across the Mercedes-Benz G55 AMG's front and rear positions, with both rated at 12V and 21W despite originating from different regulatory standards.
The 1156NA follows the ANSI standard used in the United States and Canada, featuring a BA15s bayonet base and natural amber glass coating on a clear single-filament bulb.
The PY21W follows the ECE standard used in Europe and worldwide markets, featuring a BAU15s bayonet base with amber-tinted glass on a single-filament bulb.
Although the 1156NA and PY21W share identical voltage and wattage ratings, their bayonet bases are not interchangeable. The BA15s base of the 1156NA and the BAU15s base of the PY21W have different pin offset angles, preventing cross-installation.
The 12496 is a Philips/Osram part number designating a 12V halogen bulb for specialty applications, specified for the G55 AMG's rear turn signal position during the 2004-2006 model years.
For the 2003 and 2004 Mercedes-Benz G55 AMG, the front turn signal position carries a vehicle identification number split: units built up to ID 144225 use the PY21W, while units built from ID 144226 onward use the 1156NA.
The front inner turn signal on the G55 AMG transitioned from the PY21W in 2003 to the 1156NA for the 2004-2007 model years, reflecting a shift between ECE and ANSI-standard bulb fitment within the same position.
The rear turn signal position on the 2011 G55 AMG uses the PY21W, consistent with the ECE-standard fitment also seen in the 2007-2010 rear position, while the 2004-2006 rear position uses the distinct 12496 bulb type.
The front turn signal position on the 2011 G55 AMG uses the PY21W, marking a departure from the 1156NA specified for that same position across the 2004-2010 model years.