What Causes Turn Signal Blinking Fast? How To Fix it

Automobiles have various lights that perform specific tasks. The use of the lights is among the basic things you learn from driving classes. The turn signal light comes in handy when the vehicle takes turns on the road. But what happens with the turn signal blinking fast?

Such a situation may seem pretty worrying but, it is very common, and there are easy ways to fix such. Undoubtedly, your car’s electronic gadget helps indicate the direction you’re turning while you drive.

In essence, it ensures that you keep safe driving and keep other cars from hitting yours. When the light of your turn signal starts blinking fast, it could be due to a bad bulb. Nevertheless, other components like turn signal relays and turn signal fuses could also be the culprits.

What Causes Turn Signal Blinking Fast

Why is my turn signal blinks fast, but all lights work? A quick check on your headlight and tail light, and notice your brake lights, reverse lights, and directional (turn) lights working. You may not necessarily see the lights blinking from within your car, but your dashboard’s indicators can reveal this issue.

why is my turn signal blinks fast but all lights work

Let’s say you find one or both turn signals blinking fast. Interestingly, the directional light is still working, signifying that they still receive power from the car’s battery. In some cases where you notice any of the turn lights not working, it could be due to a bad bulb, burnt from high amperage.

Then, you may have to look out for some dark colorings once you get the bulb out. With none of the turn signals working, the problem could result from the car’s fuse and relays. With that in mind, some common causes of your car’s turn signal blinking fast include:

Ground Connection Gone Wrong

The turn signal wires may soon appear old and brittle, and with time there must have been some disconnection. Thus, there is no provision of correct ground connection, which hinders the turn signal from working.

In essence, the ground connection going wrong can lead to your vehicle’s turn signals malfunctioning. A quick check on the wires would help you diagnose the problem. You can use your test light or a multimeter.

Insufficient Voltage

Another possible reason why your turn signal suddenly starts blinking fast could be the insufficient supply of voltage from the car’s power system. Such an issue further points towards the connection switch of your car has some issues.

Bad Bulb

Damaged bulbs can often cause the turn signals to blink fast, as the resistance switches may soon start malfunctioning. With this, the switch causes the light to flash repeatedly and at some greater speed.

When two bulbs in a specific direction are in good shape, the flasher relay would be conditioned to flashlights at the correct speed. You can attribute this to both bulbs draining a specific current amount. However, when you find one of the bulbs on either the left or right side damaged, it causes the relay to start flashing twice as fast.

Suppose you find your turn signal blinking fast with a new bulb; it could be due to the following:

Turn Signal Relay

A defect in the car’s flasher relay can cause the turn signal to blink at a faster speed. This case often results from water getting into the area, causing the relay pins to rust. Aside from this, the cause of the directional light blinking could be due to flasher relays that seem inadequate.

What does this mean? The original flasher relay that comes with your car is designed to suit the manufacturer’s configuration on your turn signal. In essence, it works well for the bulb’s wattage and gives off the targeted blinking speed.

Nevertheless, a replacement with brands that don’t match would cause the turn signal’s blinking speed to change. That could be the cause of your dodge caravan turn signal blinking fast. How do you tell if the relay in your car is in good shape? Well, you can listen to that “clicking” sounds that they give when power gets supplied to them.

Turn Signal Fuse

The signal fuse may be burnt, and it would help if you check to be sure that it is in good condition. If the turn signal fuse is bad, you would be needing a suitable replacement. There are various options available in the market. You can find the maxi fuse, mini fuse, and micro fuse.

Note: You may find the relay and fuse under the hoods or inside the vehicle. Kindly check with your car manual to determine the relay and fuse location of your car.

Ways to Fix the Turn Signal Blinking Fast

Whether your find your car or motorcycle’s turn signal blinking fast, it would be best to fix such problems. Doing so isn’t difficult, and you can follow the process below to fix yours. 

turn signal blinking fast with new bulb

Step 1: Inspecting the Light

It would help if you first step down from your vehicle to access the turn signal bulbs. The indication you get from your dashboard may not be enough. So, park the car and inspect the bulbs from behind and in front of your vehicle.

By now, you’ve already switched on the turn signal from inside the car. Check if any of the bulbs doesn’t turn on. Then, look further to see the bulb or bulbs that blink at a faster speed. If you find all lights working in good condition, then there are no problems to fix.

Step 2: Fixing Faulty Bulbs

In most cases, where the signal lights flash with greater speed, it is due to a faulty light bulb. Thus, you should open up the bulb’s encasing and take a close look at the bulb. You have to open your car’s hood to get to the bulb.

Some cars may require that you get out the battery, front bumper, and even the air filter box to reach the If you notice a dark fog, the bulb isn’t working correctly. Once confirmed that the signal bulb is burnt, a suitable replacement is needed.

Step 3: working on the Relay

If you notice the bulbs are in good condition but still find the turn signal hyper lighting, you should test the relay. Try listening for the click sound it makes, as a malfunctioning relay doesn’t make such a sound. Also, the signal bulb won’t receive power from a damaged relay.

Kindly note that a faulty relay would cause both the left and right signal lights to stop working. Replacing the relay may seem complicated for some folks. Hence, you may also decide to contact an expert to change the bad relay.

Step 4: Damaged Wires

Supposing the light bulb and the relay are in good condition, it could be that the turn signal light is flashing fast due to damaged wires. So, if you find your turn signal blinking fast with a new bulb, a test would be needed.

You have to conduct the test for each wire along with every connector. When you spot the malfunctioning wire, then you can fix the problem.

Frequently Asked Questions (FAQs)

Q: Is a fast blinker illegal?

Ans: A fast blinker is unlawful under the ruling of the Federal appeals court. This criminal act ruling was handed based on the incident on the 12th of December, 2013, in Georgia (Greene County). An officer had stopped a driver with his blinker working at a fast speed.

The panel of three judges considered the traffic stop that occurred that day and set up such a precedent. Nevertheless, the rapid blinking lights tell that something is wrong with the vehicle. It would be best if you get it fixed as soon as possible.

Q: How do you test a turn signal flasher relay?

Ans: You can access your car’s flasher relay after finding its location in your car. The location of the relay varies, and you can check your car’s manual for assistance. Then, move further to turn on the car’s ignition. Get your test light and ad probe the major wire that leads from the vehicle’s relay.

When you notice the light turned on, it signifies that the relay is working. Continue by getting the relay out and testing with the multimeter. You can do this by placing the meter’s wire to the control and power terminals.

Q: Where is my turn signal relay?

Ans: You may find the relay and fuse under the hoods of your car, covered with plastic that protects them from moisture. When you open the hoods of most cars, you find the relay and fuse inscribed on the plastic cover.

Nevertheless, the position may vary from car to car, as some models have the relay inside the vehicle. So you can also check the turn signal box below the steering wheel. Kindly check with your car manual to determine the relay and fuse location of your car.

Q: How much does a turn signal relay cost?

Ans: The turn relay of cars is pretty inexpensive, making it an excellent idea to get it replaced once they develop faults. You can find one at the price of $65, which seems quite fair. If you need to get your car’s relay changed yourself, then you can save some cost.

The labor fees for installing new relays often range from $102 to 122. Whether you find your turn signal blinks fast only sometimes or at all times, it could be due to a malfunctioning relay. Thus, a suitable replacement would help fix this issue.

Q: What is a LED flasher relay?

Ans: LED flashers to come constructed as integrated circuits acting like semiconductors that turn On/Off. The light emits diodes based on the car’s programs or does so sequentially. However, these lights can only get their power from the car’s battery.

Accessing this power is via the help of the relay, which supplies the power needed for the LED to give off light. Once the relay gets damaged, the LED does not get the power and stops turning the lights on.

Final Words

The turn signal is pretty essential for safe driving, and when it doesn’t light up, the driver and other motorists are in grave danger. The power for emitting the signal light comes from the car’s battery that passes through some fuse. This fuse then sends the current to the relay’s switch side.

Then, the signal light gets the power from the relay and flashes at normal speed. Still, what happens with your car’s turn signal blinking fast? It signifies a problem that you need to fix. Does your car have a turn signal blinking fast LED bulb? You can check out the possible cause and solutions in this article.

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Hi there, I am R. Hasan Tito, a mechanic, and owner of this website. My friend and I created this website to share our knowledge, expertise, and experience with our fellow mechanics' community and car users. I am a specialist and certified automotive mechanic (Both Heavy Commercial and Private Cars). I worked as a Mechanic and Mechanic Supervisor for over fifteen years at Global Rebound Automotive companies - Toyota, TATA, BMW, Nissan, TVs, and Others. Now, I enjoy my new role of leading a team of automotive experts (in their respective fields) and publish new content on a regular basis on my website and social media.

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