Skip the auto shop - Our mechanics make house calls

How Does the Turn Signal Switch Know to Reset When My Car Stops Turning?

turn signal switch

When you drive, it is not uncommon to see a motorist with a turn signal on when there is no approaching exit or turn, and obviously no intention on changing lanes or turning anytime soon. In this situation, either the turn signal cancel cam is not working or they have forgotten to turn their signal off manually. How does your car know when you finish a turn so it can turn the signal light off?

Turn signals operate in a few simple steps:

  1. Power is supplied to the turn signal lights when the signal lever is pressed. The flow of electricity to the turn signals is sent through a fused circuit and a flasher to the bulbs. The signal lever stays caught in place at this time.

  2. The turn signals continue to operate while the steering wheel is turned. Power continues to flow to the turn signals in that same manner while you make the turn. It isn’t until your turn is complete and you return your steering wheel to the center position that the signal lights turn off.

  3. The turn signals are cancelled when the steering is turned to center. As you turn the steering wheel back to the center position, a cancel cam on the steering column comes into contact with the turn signal lever inside the column housing. The cancel cam lightly presses on the signal lever and turns the signal lever off. The signal lights no longer flash.

If you are making a slight, gentle turn, or if the cancel cam is broken or worn out on your steering column, you will need to manually turn off your signal lights. A light press on the signal lever will let it spring back to the off position, turning off the signal lights.

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

Veteran and Military Driver Laws and Benefits in New Mexico
The state of New Mexico offers a number of benefits and perks for those Americans who have either served in an Armed Forces branch...
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...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance...


Related questions

Q: Steering wheel issue, side mirrors won't fold in

Hi there, thanks for writing in about your 1999 Mercedes-Benz S420. The accessories mentioned may share a fused circuit. Common faults in some electrical systems can range from blown circuit protection or a malfunctioning device such as a broken switch....

Q: Turn signals broken

The multifunction turn signal switch is the most common failure in this car line. I recommend that your have a mechanic, such as one from YourMechanic, come by and run a thorough diagnostic on your inoperative turn signal issue.

Q: When driving my car straight the steering wheel is still got play in it but what causes this?

Hi there. There are several things that can cause: tie rods, control arm bushings, tire balance, out of round tires, bent wheels, worn axles, failing wheel bearings. However, it seems like this could be a potential tire problem that I...