Turn signal doesn't light up on one side

Symptoms

• Turn signal doesn't blink on one side, front or rear
• Dash indicator arrow may blink faster than normal
• Other lights on that side work fine
• Issue is limited to a single bulb location

Likely causes

• CommonBurned out turn signal bulbTurn signal bulbs wear out with regular use like any other bulb.
• PossibleCorroded or damaged bulb socketMoisture or age can corrode the socket, preventing good contact even with a new bulb.
• PossibleBlown fuse for turn signalsA dedicated fuse failure can affect turn signals on one or both sides depending on vehicle wiring.
• Less commonDamaged wiring to that specific lightPhysical damage to wiring near that light, from an accident or debris, can cause failure.

What to do

1. Turn on the turn signal and check the dash indicator's blink speed, since a fast blink usually confirms a bulb is out somewhere.
2. Walk around the car with the signal on to identify exactly which bulb (front or rear, that side) isn't lighting.
3. Check the fuse box for a blown turn signal fuse and replace with the correct amperage.
4. Access the affected bulb and inspect it for a broken filament or dark glass.
5. Replace the bulb with the correct type and wattage, and test again.
6. If the new bulb doesn't fix it, check the socket for corrosion and clean carefully if present.
7. Check for any visible wiring damage near that light if the socket looks fine but the light still won't work.
8. Have a shop trace the wiring if a new bulb and clean socket don't resolve the issue.

Tools and parts

• Screwdriver (varies by vehicle)
• Fuse puller or pliers

When to call a pro

If a new bulb doesn't fix a dark turn signal, a shop can quickly test for a socket or wiring problem.

Safety