Fog lights on GMC vehicles are typically activated after turning on your low-beam headlights, using either a dedicated fog-light button on the headlight control switch or, on some models, the left-hand stalk. The exact method depends on the model and year.
Where the controls typically live
Most GMC models place the fog-light control on or near the headlight control cluster on the left side of the dash. In newer trucks and SUVs, look for a small fog-light symbol on the headlight control knob; press it to activate fog lights once the low beams are on. In some older or trim-specific variants, the fog function is on the multifunction stalk (the turn-signal lever) and is activated by pulling or twisting the end of the stalk.
Important note: Fog lights are intended for use in poor visibility conditions such as heavy fog, rain, or snow, and not for normal driving. Some models require the headlights to be on first before fog lights can be engaged.
Below are the common configurations you may encounter:
- Configuration A — Headlight control with a dedicated fog button. Turn the knob to Low/Auto/On, then press the button with the fog icon to enable fog lights.
- Configuration B — Fog lights controlled by the left stalk. With headlights on, pull the end of the multifunction lever toward you to switch fog lights on; pull again to turn off (some models use a push or rotate action instead).
- Configuration C — Integrated dash switch on certain trims. A separate switch near the steering column toggles fog lights to on, often with an indicator on the instrument cluster.
If your model doesn’t match one of these configurations, consult the owner’s manual or contact a GMC dealer for model-specific instructions.
Model and year variations
Sierra, Canyon, Yukon (recent generations)
On most recent GMC pickups and full-size SUVs, fog lights are activated via the headlight control switch after turning on low beams. Some trims have a dedicated fog-light button on the headlight control panel; others use a stalk-based control when the headlight switch lacks a fog button.
Acadia and Terrain (recent generations)
Fog lights are typically controlled by the headlight switch with a distinct fog button. Ensure the headlights are on low beam; press the fog symbol to engage. Some models feature integrated controls or menu options in the instrument cluster for fog-light operation.
Older GMC models
Earlier models may rely more on the multifunction stalk for fog-light control, or may not include fog lights on base trims. In those cases, check the manual for the exact procedure or trim-specific equipment.
Safety tips and best practices
Use fog lights in conditions with reduced visibility such as fog, heavy rain, or snow. Avoid using fog lights in clear conditions or during daylight when not needed, as they can dazzle other drivers. If fog lights fail to illuminate after following the correct procedure, there may be an electrical fault or a blown fuse; have the system inspected by a qualified technician.
Summary
To turn on fog lights in a GMC, first switch on the low-beam headlights, then engage the fog-light control according to your model—either via a dedicated button on the headlight control panel or via the left-hand stalk. If your GMC doesn’t respond as described, check your owner’s manual for the exact method for your year, make, and trim, or contact a GMC dealer for guidance. Understanding your specific model’s controls will ensure you use fog lights correctly and safely.