Why is My Turn Signal Blinks Fast But All Lights Work?

Sometimes turn signal blinks too fast than usual but all lights work fine. Do you know the actual reason? Why is my turn signal blinks fast but all lights work?

Car turn signal may blink fast when all lights are good due to lots of reasons including burnt-out bulbs, car sensor malfunction and faulty indicator lamps.

It can also be a result of driving on rough roads, bad ground or corrosion on the connection. Though it isn’t illegal to drive with this issue, it’s easier and cheaper to fix the problem.

Reasons Why is My Turn Signal Blinks Fast But All Lights Work?

The turn signal blinks fast mostly due to failed lamp and occasionally to a bad connection or bad ground. Driving on an uneven road may also cause the turn signal blinks faster. Below are some potential reasons of turn signal blinking fast but the bulb is good along with simple solutions:

1. Faulty Indicator Lamp

The turn signal may blink faster if your one of your car indicator lamps is out. To verify this, you have to diagnose the car system physically. If you have a car with an old system, there should be a circuit set up for every side light including the front and rear.

Remove one lamp to see if the lower draw on the circuit causing the faster blinks of the turn signal. If so, you have to replace the lamp. Otherwise, the turn signal will keep blinking faster as the lower current will take less time to do its job.

Though the circuit is set up differently in cars with newer systems, modern car electronic systems can also detect bulbs if it out. As a result, it can increase the flash speed. To fix this problem, bring the car to the auto repair shop.

2. Burn Out Bulb

Your car’s turn signal can also blink fast even when all the light working fine if the headlamp assembly, the mirror, or the rear light reaches the end of its cycle life. Burnout bulb is a common reason for this consequence. A burn-out bulb increases the output resistance and results in less current.

Hence the heater can’t become hot enough to saturate the bi-metallic strip. Since the bi-metallic dissipates a lower amount of heat than usual, it cools quicker and increases the flash rate. The insufficient current flow by a dead bulb can also electronically trigger the flashing circuit to blink fast. If so, you must replace the burnt-out bulb.

Do your car’s right turn signals flashes too fast while the left side flashes at normal speed? It is also an indication of a burnout bulb. Since taillight use LEDs, they have an internally built-in resistor to prevent hyper flashing. The resistor also fails due to getting very hot and causing the fast blinking of the turn signal.

3. Rough Road

If your car has LED and you often travel on uneven roads, you may notice the turn signal blinks fast. It’s not concerning as the LED flickering due to the vibration from road travel. As soon as you reach the flat surface, the blinking should also stop.

However, you can troubleshoot to determine if any faulty bulbs causing the issue. To do this, move the car’s taillight signal from right to left and left to right and travel for a few days. Do the same thing with the front light. If your notice any specific change on a bulb while applying rapid signal, change the bulb.

4. Lower Resistance

Do your car’s left turn signal blinking rapidly from the inside while the outside blinks fine and all lights work? It can be the result of replacing incandescent or halogens with LED headlights and Foglights. The reason is that LEDs are lower resistance and draw less voltage compared to halogen or incandescent.

So your car’s system thinks that one bulb is out. If so, replace the LED light with the correct assemblies and the problem will be solved. You can also fix this issue without removing the LED lights.

Install a resistor in series that match your car’s circuit to equal the stick resistance of a halogen system. However, you’ll have to do a little research to determine the resistance difference and pick a good spot to install the resistor.

5. Rusty Connection

Though its rear, corrosion on the contact can cause your car’s turn signal to blink faster than usual even when all the lights are working. For this particular reason, the left blinker can go into rapid fast mode and the light flashes extremely fast.

To troubleshoot, turn on the parking lights and hazards and then determine the light that isn’t blinking and causes corrosion. Then sand off all the corrosion to the light blinks at the right speed. If it doesn’t work, look for a bad socket or burn-out bulb.

6. Bad Ground

If your car fuses, connections and relays working well, still turn signal blinking fast, it can be the result of modified signal wiring or switch or bad ground. If so, the left side would blink fast intermittently, and a while back it should work fine after using hazard lights.

To verify, connect a ground wire to the negative battery terminal or clean the chassis’s unpainted part. Then connect the ground wire’s other end to the bulb socket’s metal part.

7. Other Possibilities

Some commercial cars’ turn signal bulb blinks faster due to using different tempo for their larger profile. So if you need to replace the bulb on your BMW car, make sure you are using the type of bulb that is intended for European cars.

Using non-European bulbs can cause a fast flashing situation. It is also common for LEDs to blink fast as they use minimal energy.

Are Fast Flash Turn Signals Illegal in the US?

Though it isn’t illegal to run a vehicle with a fast flash turn signal in the US by law, there have some limitations. The Department of Transportation allows max 120 flashes per minute. It means that your vehicle’s light makes 2 flashes per second while driving on the road in the USA.

In terms of your query, it’s almost impossible for a vehicle to make super-fast flashing to beat this limit. Some states may also set lower limitations than others. So whether a fast blinking turn signal is illegal or not is depend on the car’s speed and the state where you are traveling.

However rapid cycle of the turn signal is irritating to drive with and mostly indicates burnt-out bulbs. If you experience such a condition while driving, park the vehicle and investigate.

Follow your car’s owner manual’s instructions to replace the faulty bulb if required. While buying new bulbs from the parts store make sure it’s compatible with your vehicle’s system. Replacing a car’s build only takes around 15 minutes and a Phillips screwdriver.

How To Replace a Turn Signal Bulb?

It’s fairly easy to replace a car’s turn signal bulb you can perform it at a home garage. However, make sure you don’t touch the new light bulb’s glass area with bare hands. Otherwise, it can damage the bulb.

In some vehicles, you may require to remove mounting screws to take the turn signal housing before starting the replacement process. Then follow these steps:

• Open your car’s hood and find out the unit that you want to replace. Then replace the damaged turn signal bulb.
• Push down the locking tab and turn it back to take the electrical connector out.
• Rotate the socket anti-clockwise to remove the damaged bulb. In some vehicles, you may need to push the bulb down and pull out while turning to take the bulb out.
• Once removed the faulty bulb, insert the new one. If your new bulb has alignment pins, align them with the matching opening.
• Re-connect all the electrical connections and put the housing in its original place.
• Turn on the car and check the turn signal to see if it’s working properly.

FAQs

Final Words

Turn signals are crucial parts of a car for driving as these help communicate to other drivers to change direction safely. It also helps activates or lane emergency flashers. So if you experience your car’s turn signal blinks fast but all lights work, fix the problem immediately as it’s vital for drive carefully.

Remember, a malfunctioning turn signal can cost you a traffic violation and make driving annoying and risky. However, you can easily fix the too-fast blinking of the turn signal at any auto repair shop at a cheaper price.