Skip the auto shop - Our mechanics make house calls
  1. Home
  2. Articles
  3. How a Car Turn Signal Works

How a Car Turn Signal Works

turn signal

A requirement for all automakers is to equip each vehicle with proper, standard lighting. Every vehicle is equipped with several lighting systems including:

  • Headlights
  • Taillights and brake lights
  • Corner marker lights
  • Hazard or warning lights
  • Turn signal lights

Turn signal lights are important for the safe operation of your vehicle. They indicate your intentions to change lanes, turn a corner, or pull over to the roadside. While not everyone uses their turn signals as regularly as they should, their usage dramatically reduces the number of accidents and driver errors.

How Car Turn Signals Work

Turn signals require electrical power in order to illuminate the turn signal light bulbs. The circuit is protected by a fuse in the power junction block in case of an electrical fault. When the turn signal lever is activated in either direction, a circuit is completed that allows power to flow to the front and rear turn signal lights on the selected side.

When the signal lights are turned on, they are not illuminated constantly. They flash in a rhythmic pattern to draw the attention of other motorists and indicate your intention. This is achieved by routing the power to the turn signals through a flasher or module that sends pulses of power to the lights instead of a steady stream.

When you complete your turn and turn the steering wheel back to center, a cam on the steering column catches on the turn signal lever and cancels the turn signal operation. If the cancel cam on your steering column is broken or you only take a slight turn, the signals may not cancel on their own and you will need to turn the signals off by moving the signal lever on your own. Make sure to get your turn signal fixed as soon as possible.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
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

The Traveler’s Guide to Driving in Malaysia
CraigBurrows / Shutterstock.com Malaysia is a popular destination for many tourists today. The country has amazing sights and attractions that you will want to explore....
How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2422 OBD-II Trouble Code: Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed
Diagnostic Trouble Code (DTC): P2422 P2422 code definition Evaporative Emissions Control System (EVAP)...


Related questions

Q: My tail-brake lights are not working, but my top brake light is working, and the taillights are on when the headlights are on

Since the third brake light works your brake light switch is good. This vehicle has a rear brake light out sensor module in the left rear of the trunk that needs to be checked to see if brake signal is...

Q: When I shut my van off the left signal blinks. Hazards never work and the right blinker does not operate.

Make sure your hazard button is pushed in. If it's not it can cause your turn signals not to work, even when the switch is not working. Try pushing the hazard button on and off several times and see if...

Q: Turn signals

Try to turn on and off the 4 way flasher switch several times and then leave off then try turn signals again. If they still act up then you most likely have a bad turn signal switch internally shorted. ...