Why is your turn signal blinking fast? And how do you fix it?

Updated Jul 11, 2021 | Same topic: Automotive FYIs

There’s definitely something wrong, so you better pay attention.

Turn signals lights or turn indicators are important to driving. It is one of the few devices on the car that conveys to other motorists as to which direction you’re heading. Using this ensures that other drivers are aware of your intended path, and can adjust their speed and/or direction accordingly.  

Sometimes though, a car’s turn signals can go bad. One of the more common faults of these lights is that they’re blinking too fast. In more technical terms, this is called hyperblinking. In some instances, hyperblinking turn signal lights can still do the job, but if you leave it alone unfixed it might end up not working in the long run. So how does one fix a signal light that’s blinking too fast? 

Why my signal lights are blinking too fast and how to fix it 

Incorrect resistance – If you’ve upgraded to LED turn signal lights but they’re flashing too fast, then they might be receiving too much voltage. As such, you might need a load resistor kit. This part increases the load resistance of a circuit to a certain level. This is particularly needed for cars that were converted from using halogen bulbs to LEDs. Without one, the car will think that there are no headlamps installed, and will flicker your LEDs faster. To install a load resistor kit, follow the instructions provided. Most often, these kits will include a diagram, and the load resistor itself will have color-coded wires. 

A picture of a load resistor

A load resistor connected with an LED light. The reistor is the orange metal thing at the bottom

Do note that you might have to find mounting points for the load resistor and some disassembly of the car’s front panels might be needed. 

Replacing the flasher module – Another way to fix an LED signal lamp that’s hyperblinking is to replace the flasher modules. These look like small round or box shaped parts with terminals jutting out on one of their sides and are used on both LEDs and normal bulbs. To use these, simply plug them in on the stock signal light’s flasher socket. For those unaware, a flasher module controls how fast the flasher should be. If your signal light is flashing too fast, you might need a replacement flasher module as pointed out. 

Faulty bulb – If you’re bulb-type signal lights are blinking too fast, it might be that they need replacement. Simply open the turn-signal light assembly and replace the bulb.  

A picture of a car's headlamps

Depending on the car, replacing the lights will either be easy, or a lot of work

Bad grounds – Bad ground can cause shorts and incorrect voltage. To repair this, trace the ground wire from the signal light’s housing. Note the condition of the wire and if it’s loose. Also check the points where these wires are connected to. Sometimes these are dirty, or corroded. Give these spots a wipe and/or retighten them. 

Overcharging alternator – If the aforementioned fixes still don’t work, then we advise having your car’s electrical system checked. As mentioned, there are many other things that can cause hyperblinking such as your alternator might be overcharging the battery. If the turn signal blinks slower than usual, then the alternator might be undercharging instead. 

A picture of the car's alternator

The alternator is technical the heart of your car's electrical system after all

These are the common fixes for addressing a turn signal that’s blinking too fast. If you’re unsure of how to do any of these, we advise hiring a car electrician, or taking your car to your nearest casa. For more helpful car maintenance guides, keep it here on Philkotse.com

Turn signals blinking too fast: FAQ 

1. Is having a turn signal that’s blinking too fast illegal? 

Answer: It is not stated specifically that driving around with a turn signal that’s blinking too fast is illegal. According to several laws however, all lights including the turn signal lights should be in working order. 

2. How much is a replacement turn signal light bulb? 

Answer: A cheap halogen turn signal bulb can cost somewhere between Php 50 to Php 100. 

3. Is hyperblinking really that bad? 

Answer: Hyperblinking can cause damage to LED or halogen bulbs in the long run. 

4. How can I tell if my turn signal bulb is going bad? 

Answer: Signs that you need to replace a turn signal include blinking very fast, not blinking at all, or not turning on at all. 

5. How much is an LED turn signal kit in the Philippines? 

Answer: From online shopping sites, a cheap LED turn signal kit can cost somewhere between Php 150 to Php 500 depending on the brand. 

Cesar G.B. Miguel

Cesar G.B. Miguel


Cesar Guiderone B. Miguel was born and raised in Iligan City, Lanao Del Norte. He graduated in 2010 with a Bachelor of Arts in English degree from Mindanao State University - Iligan Institute of Technology. He previously worked as a freelance writer for various websites, as a member of the Iligan City Disaster Risk Reduction Management's training staff, and as a medical sales representative.

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