Turn Signal Blinking Fast: How To Fix In 5 Simple Ways?

Are you worried about your car’s LED bulb blinking too fast? Well, don’t worry as it is a common problem with a quick solution. To know how to fix the turn signal blinking fast issue, continue reading ahead with Car From Japan.

How Does The Turn Signal Work?

Turn signals are the flashing lights that indicate whether a vehicle is turning left or right. All cars feature high-mounted turn signals and brake lights.

Overall, the turn signal structure and its circuit is standard in most types of vehicle. They often include 3 main parts as follows.

Signal circuits

The signal’s source travels from the battery to the turn signal relay through the fuse. When you move the signal lever up or down to activate the signal to the right or left, the control circuit completes.

The lightbulb

It then activates and transfers electricity through a second load circuit that contains the lights in the direction you specify. The bulb is then turned on. Instead of a constant “on” state, electricity is routed through a flasher to produce the flashing action.

The flashers

Temperature-assisted flashers of turn signals are designed to bend at specific intervals dependent on electrical conditions. They are designed with a tiny ring of heat-resistant metal.

The electrical current that runs through the band causes the metal to warm up and cool down by stretching and bending in order to break or complete the circuit’s operation, resulting in the flashing action.

car blinker
Turn signals are the flashing lights that indicate whether a vehicle is turning left or right. . (Photo: Scott Goodwin Law)

Turn Signal Blinking Fast: Causes Explaining 

As we mentioned above, the turn signal is the device that indicates the direction via blinking rear and front headlights. The driver does this manually to inform other vehicles of the turns he is intended to take.

Seeing the importance of this electronic gadget, one can easily comprehend the value of its maintenance tips. However, in case the turn signals start blinking fast, there are several causes, which can lead to this unwelcome problem. 

So, before you delve deeper into its solutions, let’s take a look at what causes the fast blinking turn signal.

Bad shape of ground connection

If the combination switches are dirty and need cleaning, this issue clearly indicates that the ground connections are in bad shape. Another reason behind the turn signal flashing fast is that the screws are not installed tight enough to operate normally.

So, check your device and look for the cause, accordingly!

Faulty bulb

Even when you encounter a bulb failure in the headlamp then, also the turn signals start blinking fast. 

This mainly happens during the broken or damaged bulbs, when the resistance switches start acting abnormally by flashing the light repeatedly at a great speed.

why is my blinker blinking fast
Learn how to solve the turn signal blinking fast issues. (Photo: Hot Cars)

Insufficient voltage

Lastly, during the improper supply of voltage to the car, the indicator blinks fast; which also points towards the bad combination switch.

Thus, before you move ahead to fix the issue, determine the problem which is causing the turn signal blinking fast.

>> See more: Car Dashboard Warning Lights: Symbols and Their Meanings

Corroded light bulb socket

Typically, the bulb is inserted into the socket, and corrosion within the socket can occasionally prevent current from passing through the bulb. By scraping the interior contacts with a screwdriver, you may clean the socket.

If that limit is exceeded, you may need to use some electrical testing equipment (such as a voltmeter) to test both the socket and the bulb; or the grounding wire may be faulty or rusted. If you’re lacking in tools and knowledge, it might be time to call a technician.

While a quick flashing turn signal might be unpleasant, it also serves as a warning device for several severe problems to prevent. 

Overcharged battery by an alternator

Among all of the issues that lead to our problem today, overcharging batteries can be one of the most complicated and severe issues. 

You see, your alternator is responsible for converting the mechanical energy in your car into electrical energy so that the electrical components in your car can function properly.

However, if your alternator generates too much power, it can overcharge properly and damage your car’s electrical system. Besides the quick flash, some ways you can tell if your generator documentation is subject to excessive or non-acceptable recalls include:

  • Your battery is swollen
  • Your lights are unusually bright and blink faster
  • Your lights go out quickly
  • The battery is too hot
  • Your battery is leaking

If you think your alternator is not working properly, you should have it repaired as soon as possible to avoid further damage to your turn signal and other parts of your vehicle. 

why do my blinkers blink fast
Overcharging batteries can be one of the most complicated and severe issues. (Photo: Vehicle Freak)

The wrong type of signal bulb

If you notice your turn signal blinking fast suddenly after changing the light bulb, there may be a problem with your new-change light. You may have installed the wrong type of bulb for your turn signal. 

So if you are planning to change your turn signal at home, make sure that the new bulbs are going to fit the lighting system. Since a light bulb giving too much extra lighting might cause your blinker to blink quickly. 

Turn Signal Blinking Fast: How To Fix With 5 Simple Ways?

Check for bad grounds

For this, trace the ground wire to the termination point from the bulb housing. If the connection is loose or the wire is damaged, make sure to respectively retighten or change the wire immediately.

Else, you can clean everything in the system, if you want to be sure!

Change the turn signal relay

One of the easiest repairs ever, you can also do it on your own (if aware of the system).

To start with it, find the relay cluster and the turn signal relay in your car. Next, replace the old signal flasher relay with the new one, and the very next minute, your car is back to normal blinking.

Tip: You need not worry about the installation, as it would go in the right way easily.

Replace the turning signal bulb

Replacing the turn signal bulb in most cars is relatively easy. However, if you don’t feel comfortable changing the bulbs yourself, take your car to a trusted auto technician to do the job for you.

Remember to avoid touching the glass area of the new bulb with bare hands to avoid damaging the unit. Depending on the design of your vehicle, you may need to remove the mounts to remove the turn signal housing before starting the replacement steps.

how to fix a fast blinker
Replacing the turn signal bulb in most cars is relatively easy. (Photo: MotorTrend)

Here are the steps to follow to smoothly replace the turning signal bulb:

  • Turn off the old turn signal light by opening the hood and identifying the part that needs replacing.
  • Start the electrical connection by pushing the key down and back.
  • Turn off lights by turning the sockets counterclockwise. Depending on the vehicle type, you may need to pull the bulb straight out or push the bulb out during a turn.
  • Reconnect the new turn signal bulb. If the bulb goes out with adjustment pins on the bottom, make sure they align with the corresponding openings.
  • Reconnect electrical connections and change the housing if necessary.
  • Start your vehicle and check the turn signals to make sure the replacement bulbs are working.

The turning signal is an important component of driving. Signals help communicate with other drivers so you can safely change direction and lane or activate your emergency flash.

Resolve resistance-related problems

If you just changed your vehicle’s normal turn signal bulb with a new LED turn signal bulb, you can have a chance to encounter resistance difficulties.

Because the car flash module relies on circuit resistance to work properly, connecting a low-resistance LED signal bulb might cause the flash to cycle fast, as if the bulb’s filament was turned off.

In this case, inline resistors can be acquired and placed to restore the module-specific flasher’s operational characteristics.

Further electrical troubleshooting

If the above solution doesn’t make the turning signals operate normally then, you can go for further troubleshooting. During this, you can trace down any loose wire (it can be ground or power wire) and fix it as soon as possible.

No doubt, it can be painful for your neck as you have to bend down but that’s the only way you can get to it.

how do i fix a fast blinking turn signal
Factors causing turn signal blinking fast. (Photo: Alamy)

FAQs on Turning Signal Blinking Fast

1. How fast should turn signals blink?

Working turn signals have an average cadence of 60 to 120 blinks per minute, according to SAE Standard J590b. When anything is wrong, the blinking speed or clicking sound may increase.

2. Does every turn signal blink at the same speed?

The majority of turn signals are powered by an electromechanical mechanism. Two separate turn signals seldom flash at the same pace, even among automobiles of the same make and model, due to manufacturing tolerances, battery state of charge, ambient temperature, and a variety of other factors.

3. Are fast turn signals blinking illegal?

The turn signal flashes fast may be considered inappropriate by federal authorities.

4. How much do you have to pay to fix a fast blinking turn signal?

The typical cost to replace a turn signal bulb is between $80 and $110. Prices vary based on the type of automobile you own and the type/quality of the auto center you head to. 

5. What are the symptoms when a turn signal flasher of a car goes bad?

The danger or turn signal lights not working is the most prevalent indication of a damaged or non-functional turn/hazard light. 

When the turn signal lever or danger light button is engaged and the flash is broken or has any internal faults, the light may malfunction or become entirely unresponsive.


Hope this guide can be useful for you but in case you face trouble while following the second remedy then, it’s better to consult the manual guide of the car. Or else, you can contact the car’s professionals to help you with the turn signal blinking fast!

For more car maintenance tips, follow Car From Japan today!