Category: Cars, Tech, Gadgets

Beyond the instrument cluster, your Sierra's HVAC control panel, headlight switch, and radio illumination can also be converted to LED. These components typically use the same 194-size bulbs or smaller 74-size wedge bulbs. Accessing them requires more disassembly—removing the dashboard bezel and unscrewing the control units. The process is tedious but rewarding. One common issue when converting HVAC controls is that LEDs are so bright they may bleed through the opaque plastic intended to block light. A simple fix is to lightly sand the LED lens with fine-grit sandpaper to diffuse the beam, or to use lower-output LED bulbs. For the headlight switch and power window switches, small T3 Neo-Wedge or T5 LEDs are often required. Always verify bulb sizes by checking your owner's manual or pulling the original bulbs before ordering.