Peterbilt 382 Map Light Bulb Size

Additional Notes

• The Peterbilt 382 uses the 912 bulb for the map light across the 2011-2017 model years.
• The 912 is an ANSI-standardized bulb type, meaning its specifications are governed by a recognized North American standard applicable in both the US and Canada.
• The 912 uses a wedge-style base, which is a baseless design where the glass envelope itself is pinched at the bottom to form a friction-fit connection within the socket.
• The T15 designation refers to the bulb's tubular shape, with the numeric portion indicating a width of 15 eighths of an inch across the widest point of the glass envelope.
• The 912 operates at 12 volts, which is consistent with the standard electrical system voltage found in most commercial vehicles.
• The 912 is rated at 12 watts, reflecting a relatively low power draw suited to interior courtesy and reading light applications.
• The 912 is a variant of the 921 bulb. While both share the same T15 wedge form and 12-volt rating, the 921 is rated at 18 watts, making the two bulbs electrically distinct despite their physical similarity.
• Because the 912 and 921 share the same wedge base and physical form, the 921 is capable of fitting the same socket, but its higher wattage output may exceed the thermal and electrical tolerances of fixtures designed for the 912.