Turn Signals

Blinkers or turn signals help communicate our intended vehicle direction. By activating the turn signal switch you are able to alert people around your vehicle by flashing a light bulb at the front and rear of the vehicle. Turn signals first appeared on vehicles in 1939 and since then have become standard equipment for all vehicles. The turn signal system is operated by a turn signal switch, which can activate either the right or left side blinker. The bulbs at the front and back of the vehicle are connected to the switch.

Turn Signal Switch
Turn Signal Switch

A turn signal flasher unit is incorporated into the system and is used to break and reconnect the blinker bulb circuit. This device creates the blinking light action at the front and rear of the car. When a blinker fails the system stops flashing, the lights just stay on. The flasher unit has shorted internally and replacement is required. If the blinker system flashes quickly on one side or the other there is a failed bulb somewhere in the system. Inspect front and rear bulbs and replace as needed and recheck system.

Signal Flasher
Signal Flasher

If the blinker system is not operating check the fuse first, then try replacing the flasher. If the flasher short circuits, it will cause the connection inside the flasher to fail, replace the flasher and recheck system. Always replace blinker bulbs with manufacturers recommend bulbs, resistance is important and must be correct.

If further technical assistance is needed, ask our team of certified car repair technicians.

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Written by
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35 years in the automotive repair field, ASE Master Technician, Advanced Electrical and Mechanical Theory.


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Article first published (Updated 2013-11-21)