This device is used in both the hazard warning lights and the turn signal systems. The turn signal flasher itself will look different depending on the year make and model of the vehicle. General Motors vehicles most commonly use an aluminum cylinder type housing to contain the flasher assembly.
Ford and some other foreign car manufacturers make their flasher assembly look like a standard relay. In either case they contain a temperature sensitive bimetallic strip and a heating element. This bimetallic strip is connected to one side of a set of contacts.
When the current is disconnected it allows the bimetallic strip to cool. Then it will automatically close the circuit to illuminate the bulb once again. This intermittent on-off interruption of current flow makes the turn signals work correctly and notifies other drivers that you are turning.
Where are turn signal flashers
You can use this sound when they are functioning properly to track down the location of the turn signal flasher. When the turn signals or hazards are not working finding the flasher can be more difficult. I recommend that you get a quality online service manual that will provide pictures of the component location.
Turn signal problems
The turn signal and hazard systems are designed to operate a specific number of bulbs. If one of those bulbs has an open filament and is not working the turn signals may flash faster than normal and on some models may flash slower or not work at all. It is always a good idea to start by checking the operation and verifying that all of the bulbs are okay before you move on to checking the turn signal flasher.
Although it is not as common, problems with the switch are also one of the possibilities. If you're flasher tests good and all of the bulbs are working properly it may be time to check the turn signal switch itself. And the same thing goes for the flasher switch. Note on some models like the mid nineties Pontiac Grand Am the turn-signal switch is a common problem.
When it comes to electrical diagnosis it is a good idea to follow a set path and confirm failed components before you replace them. An automotive meter is an inexpensive and handy item to have in your toolbox. For more information about common auto repairs this next link will take you back to the main page for the blog about auto repair.