Turn signals are not only an important safety precaution, but also a legal requirement. You want to make sure yours are working, otherwise drivers behind you won’t be alerted to your turns, and you could end up getting pulled over and given a "fix-it" ticket. There is no warning light for when your turn signals aren’t working, but your signal will typically blink faster when the light is close to going out.
Common reasons for this to happen:
Blown fuse: Fuses provide overcurrent protection for electrical units. They are low-resistance resistors that limit excessive currents, which powers electrical devices without damaging them. Like all of the lights on and in a vehicle, turn signals rely on a fuse. When the fuse blows, electric power to the turn signals will be shut off entirely.
Burnt out bulbs: As with all light bulbs, turn signal lights can burn out and die. Turn signal lights usually last many years before burning out, however they can die earlier than expected with high frequency of use.
Dirty bulb sockets: If dirt or debris gets into the turn signal socket, it can interrupt contact between the socket and the bulb. This can make turn signals work intermittently, or not at all. Oxidization can also cause this issue, effectively interrupting the circuit.
Bad turn signal switch: The turn signal switch is responsible for sending the sign and current to the turn signals when you try and turn them on. If the switch malfunctions or breaks, there is no communication between the turn signal lever and the turn signal light.
Bad flasher module: Power on a traditional turn signal flasher unit is provided to the system via the flasher unit. A fused, switched lead is run from the fuse to the flasher, so that it only receives power in the "Hot in Run" position. If this malfunctions, your signals may turn on, but it usually won’t flash.
What to expect:
A top-rated mobile mechanic will come to your home or office to determine the source and cause of the nonworking turn signal, and will then provide a detailed inspection report that includes the scope and cost of the necessary repairs.
How it's done:
The mechanic will start by identifying which signal is the issue, and then examine the bulb, socket, and fuse to determine if one of these is at fault. If the problem does not reside with one of these parts, then the mechanic will shift their attention to the signal switch and flasher module.
How important is this service?
You won’t do damage to your vehicle by driving it with a malfunctioning turn signal light, but it is illegal and unsafe, so you should have a mechanic check it out immediately.