Skip the auto shop - Our mechanics make house calls

Symptoms of a Bad or Failing Hazard / Turn Signal Flasher

turn signal flasher

Bad or Failing Hazard / Turn Signal Flasher Inspection

by a top-rated mechanic at your home or office

The hazard and turn signal lights found on the vast majority of road going vehicles are controlled by a flasher, which is commonly referred to as a relay. The flasher is an electrical component that serves as the switch that allows the lights to flash on and off. They come in a variety of shapes, sizes, and designs, which will vary according to the specific needs of the vehicle.

When current is applied to the relay the circuit inside cuts on and off, which results in the clicking sound of the relay, as well as the flashing of the turn signal or hazard lights. While they are a very simple component in both design and operation, flashers play an important role in the overall driveability of a vehicle, and can compromise safety when they fail. Usually a bad or failing flasher relay will produce a few symptoms that can alert the driver of a potential issue.

HAVE SYMPTOMS OF CAR TROUBLE?
Get an $80 diagnostic
by a top-rated mechanic at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

1. Turn signals or hazards do not function

The most common symptom of a bad or failing turn signal / hazard flasher is hazards or turn signal lights that do not function. If the flasher breaks or has any internal issues it can cause the lights to malfunction, or not respond at all when the turn signal lever or hazard light button are pressed. While this will not necessarily cause engine performance issues, it will leave the vehicle without functioning hazard lights, and more importantly turn signals, which can be a compromise in safety.

2. Turn signals or hazards stay on

Another symptom of a faulty flasher relay is hazards or turn signal lights that stay on. If the flasher has any sort of internal short it may cause the hazards or signals to stay on when they are activated, instead of flashing. While they may still light up, the lights will not be able to serve their intended purpose of signaling a turn or emergency situation. These same symptoms can also be caused by electrical issues, so having the vehicle properly diagnosed is highly recommended.

HAVE SYMPTOMS OF CAR TROUBLE?
Get your car fixed at your home or office.

Get a quote · Book an Appointment · Our expert mechanics come to you.

3. Additional lights are not working

In some instances you may also find that certain other lights, such as headlights, running lights, and even brake lights may malfunction along with your hazards. Certain vehicles will wire other lights through or with the flasher, and as a result will also have an issue if the flasher fails.

While issues with the turn signal hazard relay will not normally affect the driveability of the vehicle, they can cause problems that can compromise vehicle visibility and safety. While flasher relays are not complicated components, they can sometimes be difficult to diagnose due to the highly complicated nature of electrical systems. If you suspect that your vehicle’s turn signal hazard flasher may be having an issue, have the vehicle diagnosed by a professional technician, such as one from YourMechanic, to determine if the relay should be replaced.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Still not sure about your car's issue?
Diagnose your car
What kind of issue are you experiencing?
Brakes are squeaking
Car is not starting
Car is overheating
Car is shaking (vibrating)
Fluids are leaking
Heating and A/C
Smoke or steam is coming out of the car
Warning light is on
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

More related articles

How to Get a Louisiana Driver's Permit
s licensing program. The first step in this program is to obtain...
Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
P0291OBD-II Trouble Code: Cylinder 11 Injector Circuit Low
P0291 code definition When your vehicle’s PCM registers the P0291 code, it means that a voltage reading came from the fuel injector circuit – for cylinder number 11’s fuel injector –...


Related questions

Q: Turn signals and emergency flashers not working

This is most likely due to a blown fuse or because the device that flashes the lights has failed. The component that flashes the lights interrupts the electricity flow to the lights to make them flash. This "flasher" as it...

Q: Brake light switch stuck.

From what is sounds like, your brake lights constantly appear to be on. It's not uncommon for aftermarket parts, such as brake light switches, to fail prematurely. I would have a certified mechanic like YourMechanic verify the problem with the...

Q: Turn signals are not working

Hello. The turn signal malfunctions you describe can be caused by a few different things. If you have already checked the fuses and replaced the switch then the next things I would look at are the turn signal relay and...