Symptoms
- One side's turn signal blinks much faster than the other
- Dash indicator arrow blinks quickly too
- Exterior light doesn't appear to be flashing on that side
- Issue is isolated to one specific corner of the car
Likely causes
- CommonBurned out turn signal bulbMost vehicles are designed to speed up the flasher rate as a warning when a bulb is out.
- PossibleBad bulb socket or corrosionA corroded socket can cause a poor connection that mimics a bad bulb.
- PossibleWrong wattage bulb installedInstalling a bulb with a different wattage than stock can cause fast blinking, especially with LED conversions.
- Less commonWiring issue to that specific lightDamaged wiring near that light can also trigger a fast blink pattern.
What to do
- Turn on the turn signal and walk around the car to see which specific bulb isn't lighting up.
- Check that bulb for a broken filament or dark, discolored glass, both signs of a burned out bulb.
- Replace the bulb with the correct type and wattage specified for your vehicle.
- If you recently installed LED bulbs, check if you need a matching load resistor to prevent fast blinking.
- Inspect the bulb socket for corrosion and clean gently if present.
- Test the turn signal again after replacement to confirm normal blink speed has returned.
- Check the same bulb again after a few days, since a fast return of the fault can mean a socket or wiring issue.
- Have a shop check the socket and wiring if a new bulb doesn't fix the fast blink.
Tools and parts
- Screwdriver (varies by vehicle)
- Replacement bulb
Turn signal bulbSearch: “turn signal bulb for [your car make model year]”
LED load resistor (if using LED bulbs)Search: “LED turn signal load resistor”
When to call a pro
If you're not comfortable accessing the bulb (some are behind panels or require removing the headlight assembly), a shop can replace it quickly.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.