To replace a turn signal light, first purchase the bulb appropriate for the vehicle's make and model. Unscrew the tail light cover and remove the light casing as far as possible without detaching the wiring from the vehicle. Remove the plug holding in the bulb by turning it a quarter of the way around. Remove the problem bulb, and replace it.
Once the turn signal light is replaced, reattach the plug to the back of the bulb, and tighten. Place the light casing back into its structure. Screw the tail light cover back in place. Check the bulb by activating the turn signal to ensure it functions properly.
To change the front turn signal lights, first pop the hood, and remove the headlight assembly. Remove the plug holding in the turn signal light by turning it counterclockwise, and then take out the malfunctioning bulb. Replace it with a new bulb, and reinstall the plug. Replace the headlight assembly, close the hood, and test the turn signal.
Depending on the vehicle's make and model, a variety of tools can be used to replace a turn signal bulb. Gather a Phillips-head screwdriver, a ratchet, small wrenches and a socket set before beginning.
The process of replacing a turn signal light takes around 20 minutes when done at home, and the only cost incurred is that of the new bulb, which, depending on the vehicle's make and model, costs between $3.00 and $20.00. Opting to have a mechanic change the turn signal light incurs heavy labor costs. The procedure could cost upwards of around $120.00, as of 2015.