Driving down a dark winding road when suddenly you notice one of your headlights has gone out. The unmistakable orange headlight warning symbol has lit up on your dashboard. Should you keep driving or pull over immediately?
The headlight indicator light means one or both of your headlights are not working properly. You can likely keep driving, but should get it checked out soon.
In this comprehensive guide, we’ll cover what triggers the headlight indicator to come on, common culprits behind it, what drivers should do when they see this warning light, key things to know about how it functions, frequently asked questions, the symbol’s design across makes/models, pros and cons, and critical safety reminders.
Table of Contents
What is the Headlight Sign and When Does it Come On?
The headlight sign, also referred to as the headlight indicator, headlight warning light, or high beam indicator, is an orange-colored symbol of a headlight housing that illuminates on your vehicle’s instrument cluster if there is a problem with one or both headlights.
It is different than the blue high beam indicator that comes on when your high beams are active.
The headlight indicator illuminates when the following occurs:
- One or both headlight bulbs burn out
- An electrical issue with headlight wiring, switch, module, or fuse
- Daytime running lights malfunction (if equipped)
- Headlight housing is damaged causing a beam misalignment
The symbol typically comes on once the headlights are manually turned on or activate automatically at night (in vehicles with light sensors). However, it remains off during daylight hours in some makes/models.
If you see this warning light come on while driving at night, it likely means one of your headlights is out and ongoing drivers should be alerted.
5 Main Causes of the Headlight Warning Light
There are a few common culprits that trip the headlight indicator light on your dashboard. Here are the 5 main reasons this symbol illuminates:
1. Burned Out or Damaged Headlight Bulb
The simplest and most common trigger for the headlight sign is a headlight bulb that has burned out or been damaged.
Headlight bulbs eventually burn out over time like any other light bulb. Possible damage includes:
- Cracks or chips in the glass housing
- Filament breakage or malfunction
- Moisture or condensation build up inside the bulb
If it is just a basic bulb outage, the fix is straightforward – simply replace the bad bulb.
2. Problem with the Headlight Switch
The headlight switch is responsible for turning your headlights on and off when rotated or flipped. Issues with bad contacts inside the switch can cause connections to fail resulting in the headlight warning light. Warning signs include:
- Headlights cutting in and out intermittently
- Switch not triggering high beam mode
- Flicking switch repeatedly to get lights on
- Unusual noises when operating switch
Replacing the switch will be needed if it is original to the car and worn or if the contacts become too corroded.
3. Faulty Headlight Wiring
The wiring that runs from your headlight switch out to each individual headlight housing can short, break, corrode, loosen, or become disconnected – causing the indicator to activate.
In most cars, power flows from the switch to low and high beam bulbs on one headlight circuit and the other headlight on a separate circuit. If wires are crossed or connections broken, it interrupts the circuit.
Possible wiring issues include:
- Short circuit due to exposed/damaged wires
- Corrosion build up on connections
- Loose plugs to headlight bulbs
- Cracks or damage to wire insulation from heat or rubbing
Any damaged wiring will need to be repaired or replaced. Proper connections also need to be verified.
4. Malfunctioning Daytime Running Lights
Many modern vehicles come equipped with daytime running lights (DRL) – dedicated lights that automatically turn on when your car is operational to increase visibility to other drivers during daylight hours.
DRLs are typically mounted within the headlight housing. Problems with the DRL module can cause issues with headlight functionality and trigger the indicator light unexpectedly. Potential DRL issues:
- Faulty LED bulbs
- Software glitches
- Short circuit in DRL control module
- Bad DRL relay
If the problem points to a DRL malfunction, the module will likely need replacement by a dealership or shop.
5. Faulty Lighting Control Module
The lighting control module (LCM) operates and monitors your vehicle’s entire exterior lighting system. It contains an onboard computer receiving sensor inputs and relaying signals to lighting components.
The LCM can essentially “think” your headlights are malfunctioning when other factors induce false sensor readings. It then turns on the headlight warning symbol.
Typical lighting control module issues that can occur:
- Bad circuit relay
- Software calibration errors
- Ground wire defects
- Damage or corrosion to module components
Diagnostic trouble codes can precisely pinpoint LCM issues. But replacement of the entire module is often needed.
What to Do When the Headlight Warning Appears
Seeing your dashboard suddenly light up with the headlight indicator while driving should grab your attention. Here’s what you should do:
- Stay Alert – Be extra vigilant in watching for pedestrians, animals, and other cars since others may have difficulty seeing your vehicle. Put on hazards if concerned.
- Test Lights – Next safe chance, pull over and test lighting function. Turn headlights on and walk around car to inspect beams.
- Get Inspected – Schedule service appointment to have electrical system inspected and cause of warning light diagnosed.
- What Can Be Tested – Before heading to the shop, check bulbs first for burn outs and toggle the headlight switch several times to check for cut out issues. Also carefully inspect condition of wiring harness. These tests can provide helpful clues to share with your mechanic.
Ideally you should schedule repair work as soon as realistically possible. The indicator means critical safety lighting is compromised.
5 Key Things to Know About the Headlight Out Warning
Beyond understanding what causes the headlight indicator to turn on, here are 5 general key facts drivers should know about this dashboard symbol:
- Indicates an Electrical Problem – The light is signaling there is a wiring, switch, bulb, fuse, or component failure in the headlight electrical circuit.
- Doesn’t Specify Bulb – The symbol does not relay which headlight actually has an issue (left or right side) or if it signifies a high or low beam outage. You’ll need to visually inspect this yourself.
- On Solid or Flashing – Behavior of the light (solidly lit or flashing) depends on the vehicle make and model. Check owners manual for details.
- Alerts Other Drivers – Having an exterior headlight out puts you and others at risk. The indicator light serves to warn surrounding drivers one headlight may be out when illuminated.
- Often Required for Inspection – Most states require properly working headlights to pass annual vehicle inspection. The headlight warning light being on will result in an inspection failure until fixed.
So in summary – the headlight sign turning on is no small matter, even if it ends up being remedied by something as simple as replacing a bad bulb.
Frequently Asked Questions
Below we answer some of the most common FAQs about the headlight warning light:
Is it Safe to Drive With the Headlight Out Warning Light On?
It depends. Driving relatively short distances to get home or to a shop after dark is generally safe for a single burnt out headlight. However, taking extended night trips or driving in hazardous conditions should be avoided until repaired. Use extra precaution.
How Soon Does the Headlight Warning Light Come On?
In most cars, the indicator illuminates immediately or within a few seconds of an electrical issue occurring in the circuit. However, it may not appear until headlights are manually turned on.
Will My Car Pass Inspection With the Headlight Sign On?
Unfortunately no. Having the headlight indicator illuminated, even for a minor bulb outage, typically results in an automatic failure of annual state vehicle safety and emissions testing. It signals critical lighting equipment is not working as intended. Resolve the underlying cause first before attempting re-inspection.
What is the Average Cost to Fix an Issue Causing the Headlight Indicator?
Costs vary dramatically based on whether it is a simple bulb replacement vs complex wiring repair or control module replacement. Bulbs and fuses are under $20. On average, expect to pay $150-350+ to fix many wiring or switch issues causing the warning light.
Key Takeaways about the Headlight Out Warning
Driving with one headlight out is not only illegal in most states, but poses a significant safety risk to both you and other motorists not properly alerted.
Here are the core takeaways to remember about the headlight indicator:
- Illumination signals an electrical issue with the headlight system
- Should be diagnosed and repaired soon to restore night visibility
- Check bulbs first before assuming complex electrical faults
- Use hazards and drive cautiously until fixed
Don’t ignore this critical dashboard warning light! Schedule an inspection as soon as realistically possible.
Headlight Warning Light Symbol Design Varies
While all vehicles feature a similar headlight indicator light when issues arise, dashboard symbols can differ slightly in appearance between makes and models when illuminated.
Here’s a breakdown of key dashboard light specs by manufacturer:
|Abstract headlight with internal lines or beam
|Only when headlights on
|Realistic headlight housing depiction
|With engine start
|Simple circle with arc base meant to represent headlight bulb
|Only when headlights on
|Realistic headlight adaptation featuring lines suggesting housing and bulb
|Only when headlights on
|Realistic headlight portrayal with small circles as bulbs
|Only when headlights on
Check your own make and model to confirm the exact warning light appearance and behaviors. Symbols can also differ across model years. Refer to owners manual for specifics.
Pros and Cons of the Headlight Out Warning Light
While an annoyance and cause for concern when illuminated unexpectedly, the headlight warning indicator has several notable benefits but also a few downsides drivers should be aware of:
- Alerts driver immediately there is an outage
- Indicates to surrounding traffic potential issue
- Quick bulb or fuse fix in some cases
- Prevention of bumper and front end damage
- Doesn’t specify bulb location (left or right)
- Poor placement can make light hard to notice
- No warning if both lights fail
- Masks underlying issues if wiring or switch fault
So on balance – the warning light does more good than harm in making sure a headlight malfunction gets addressed. Just be aware it is not a perfect fail safe system.
Seeing the orange headlight indicator illuminate on your dashboard while driving should not be ignored. It signifies a very real problem with the electrical systems powering critical nighttime headlights – likely a burnt out bulb.
This warning symbol first and foremost serves to get a driver’s attention that one or both headlights may be compromised or not functioning normally. This alert is important both for the operator’s own visibility as well as surrounding cars.
Addressing the underlying trigger, whether a basic bulb replacement or complex wiring repair, should be done soon for safety. Use hazards when driving and take extra precaution until fixed. And when you see the headlight sign appear, at least you now know exactly what it means!