The fog light symbol shows a lamp beside three beam lines crossed by a vertical wavy line. The front fog light icon has beam lines extending to the left and angled downward. The rear fog light icon is reversed, with horizontal beam lines extending to the right. You will normally find the same icon on the switch and in the instrument cluster.
To turn on fog lights, first switch on the ignition and the exterior lights required by your vehicle. Find the fog light symbol on the steering-column stalk, rotary light dial, dashboard button or touchscreen. Activate the control, then check for the matching indicator in the instrument cluster. Front indicators are commonly green; rear indicators are commonly amber. Exact controls vary, so use the owner’s manual when the switch is unclear.
What Does the Fog Light Symbol Mean?
An illuminated fog light symbol is an operating indicator, sometimes called a telltale. It shows that the driver has activated the front or rear fog light circuit. It is usually a status light, not a fault warning.
The icon combines three simple elements: a lamp shape, beam lines and a wavy vertical line representing fog. The direction and angle of the beam lines distinguish the front fog light symbol from the rear fog light symbol.
Vehicle controls and dashboard indicators use standardized identifiers to help drivers recognize functions. In the United States, Federal Motor Vehicle Safety Standard No. 101 sets requirements for the location, identification, color and illumination of listed controls and telltales. The exact appearance can still differ slightly with the instrument panel, market and vehicle generation.
Front vs Rear Fog Light Symbols
Do not identify the icons by color alone. Follow the direction of the beam lines first, then use the color as a second clue.
| Indicator | How to recognize it | What it means | Common color |
|---|---|---|---|
| Front fog light | Beam lines extend left and angle downward through the wavy line | The front fog lamps have been switched on | Green |
| Rear fog light | Beam lines extend right and run horizontally through the wavy line | The rear fog lamp has been switched on | Amber or yellow |
The front symbol represents a low, downward-controlled forward beam. The rear symbol represents light projected straight behind the vehicle. This matches their different jobs: front fog lamps help the driver see the near-road area, while rear fog lamps help following traffic see the vehicle. For the full functional explanation, read what fog lights are and how they work.
How to Turn On Fog Lights
- Switch on the ignition. The vehicle usually needs to be in its normal operating mode before the exterior lights can work.
- Turn on the required exterior lights. Many vehicles require the parking lights or low-beam headlights before the fog lights can be activated.
- Find the fog light control. Look for the fog light symbol on a stalk collar, rotary dashboard dial, separate push button or lighting menu.
- Activate the correct function. Turn, pull or press the control once for the front fog lights. Vehicles with a rear fog lamp may use a second position, a separate button or another turn of the collar.
- Check the instrument cluster. The corresponding front or rear fog light indicator should illuminate.
- Confirm the lamps outside the vehicle. The dashboard icon shows that the function was commanded, but a failed lamp, connector or circuit can still prevent actual light output.
These steps describe the most common sequence, not a universal switch design. For example, an official Mazda owner’s manual requires the headlight switch to be in an allowed position before its front fog light switch works, and the instrument-cluster indicator then illuminates. Other vehicles may use a pull-out dial, a dedicated button or a screen control.
Where Is the Fog Light Switch?
Most vehicles use one of the following control layouts:
Collar on the lighting stalk
Look for a second rotating ring on the turn-signal or headlight stalk. The main ring may control the headlights, while the smaller collar carries the front or rear fog light symbol.
Rotary dashboard light dial
Turn the main dial to the parking-light or low-beam position. Depending on the vehicle, pull the dial outward one step for the front fog lights and a second step for the rear fog light, or press a nearby fog light button.
Separate button or touchscreen
A dedicated button may sit beside the steering wheel, on the center panel or within the vehicle’s exterior-lighting menu. Do not search through a touchscreen while moving. Learn the control position before driving in low visibility.
How to Turn Fog Lights Off
Return the switch, button or stalk collar to its previous position, then confirm that the dashboard symbol goes out. Some vehicles also switch the fog lights off when the headlights or ignition are turned off. Others retain the control position and reactivate the fog lights the next time their operating conditions are met.
Do not assume an automatic headlight setting manages the fog lights in every vehicle. Check the instrument cluster after restarting and switch the fog lights off when reduced visibility has cleared.
Why Won’t the Fog Light Symbol Turn On?
Start with the operating conditions before replacing parts. A fog light system may be working correctly but locked out by another switch position.
| What you see | First check | Next step |
|---|---|---|
| No symbol and no fog lights | Ignition, parking-light or low-beam position, and the correct fog switch | Check the owner’s manual, then inspect the fuse and switch circuit if the sequence is correct |
| Symbol is on but both lamps are off | Power supply after the control, relay, fuse, shared connector and ground | Test the circuit with the vehicle wiring information before replacing the lamps |
| Symbol is on but one lamp is off | The failed side’s lamp, bulb, connector, corrosion and wiring | Compare voltage and ground at both sides to isolate the fault |
| Aftermarket lamps will not switch on | Connector pinout, harness, relay, switch logic and vehicle configuration | Confirm the kit matches the vehicle and installation method |
A replacement lamp should not be selected from the dashboard icon alone. Check whether the vehicle uses a replaceable bulb, a complete fog light assembly, a vehicle-specific bracket or an auxiliary-light kit. If replacement is required, compare the fitment and optical options on the LOYO LED fog lights page.
Does the Fog Light Symbol Prove the Lamps Are Working?
No. The indicator confirms that the fog light function has been activated or that the vehicle recognizes the commanded state. It does not always monitor the light output from each lamp. A burned-out light source, loose connector, damaged harness or poor ground may leave the dashboard indicator on while one or both fog lights remain dark.
Verify operation from outside the vehicle or by checking the light reflected from a wall. For front fog lights, confirm that both sides illuminate and create a low, wide pattern. For a rear fog lamp, confirm the bright red lamp is active without confusing it with the brake light.
When evaluating an aftermarket fog light system, check the lamp, connector, harness, relay, switch and vehicle logic together. At LOYO, these interfaces are considered during vehicle-specific and custom fog light development because a correctly illuminated switch cannot correct a mismatched pinout, unstable connector or unsuitable bracket.
Fog Light Symbol FAQ
What does the front fog light symbol look like?
The front fog light symbol shows a lamp with beam lines extending to the left and angled downward through a vertical wavy line. Its dashboard indicator is commonly green.
What does the rear fog light symbol look like?
The rear fog light symbol is reversed. Its horizontal beam lines extend to the right through a vertical wavy line. The dashboard indicator is commonly amber or yellow.
What does the fog light button look like?
Look for a lamp shape beside three beam lines crossed by a wavy vertical line. Downward-sloping lines indicate the front fog lights; straight horizontal lines indicate the rear fog light.
Do I need to turn on the headlights before the fog lights?
Many vehicles require the parking lights or low-beam headlights to be on before the fog light switch will work. The required setting varies by vehicle, so check the exterior-lighting section of the owner’s manual.
Why is the fog light symbol on but the lamp is not working?
The dashboard indicator may confirm only that the function was switched on. A failed bulb or assembly, loose connector, damaged wire, fuse, relay or ground problem can still prevent the lamp from producing light.
Do fog lights turn on automatically?
Some vehicles can reactivate fog lights when automatic exterior lighting meets the required conditions, while others require manual operation each time. Do not assume the AUTO headlight setting controls the fog lights; verify the indicator and the owner’s manual.
Is the fog light symbol the same as the high-beam symbol?
No. The fog light symbol includes a wavy vertical line and uses a low-beam-line pattern. The high-beam symbol normally uses straight horizontal rays without the wavy fog line. See the full driving lights vs fog lights comparison for the difference in beam purpose.