Troubleshooting a Turn Signal that Won't Turn On

turn signal light on the back corner of a vehicle

Your car's turn signal is a critical safety feature because it alerts other drivers and pedestrians to your intentions on the road. The following tips will help you troubleshoot your turn signal if it ceases to work properly.

1. Bulb

If the light fails to blink after operating the relevant lever inside the car, even though the clicking sound is normal, the problem is probably the light fixture. When you flip the lever, it may also make a quick clicking sound that can indicate a burnt-out bulb.

Determine whether the light needs to be disassembled from the inside or the outside of the car and remove it in order to replace the turn signal bulb. Before inserting the new bulb, use a clean cloth to wipe the inside of the socket in case any debris or rust has settled there. Make sure that the new bulbs are the correct voltage to ensure they do the job properly.

2. Fuse

pulling a blue fuse from engine fuse panel

If you find that you are experiencing problems with other aspects of the lighting system, it will be a good idea to replace the related fuse. Check the car’s instruction manual to get confirmation of the location of the fuse panel and gain access to it. Ensure that you have pinpointed the correct fuse before replacing it.

3. Flasher Unit

The flasher unit is used as part of the system that operates the turn signal and is necessary to make the light flash on and off. It connects and disconnects the circuit to create this situation. If this is faulty, it could prevent the light from working at all. Test whether the flasher unit is at fault by removing it and fitting a jumper wire between the two terminals. If the indicator lights remain on, the flasher unit must be replaced to rectify the problem. Ensure that the replacement is of the correct voltage so that the level of illumination is sufficient.

4. Wiring

hand on a turn signal arm

The lighting is part of the car’s electrical system and part of this goes towards powering the turn signal. If there is a problem with the wiring system, it is possible that this will affect the signal. If the wires have not been grounded properly, this is likely to affect the signal and stop it from working. Where the wiring has become defective, you are likely to find that other components attached to the electrical system are also failing to work correctly. Similarly, if the car has not been grounded properly, the electrical system can fail. Rectify this by checking the wiring within the car, or having a professional do it.

5. Signal Switch

The lever that operates the turn signal is attached to the steering column within the vehicle and can prevent the light from working if it is defective. This should be included as part of the wiring inspection to ensure that it remains securely fixed in place.