Hazard lights won't turn on or flash

Symptoms

• Pressing the hazard button does nothing
• Hazards flash very fast or very slow
• Turn signals also don't work (often linked to hazards)
• Hazard button lights up but exterior lights don't flash

Likely causes

• CommonBlown hazard/turn signal fuseHazards and turn signals often share a fuse and flasher relay.
• CommonFailed flasher relayThis small relay controls the flashing rate and can fail, especially if turn signals are also affected.
• PossibleFaulty hazard switchThe hazard button itself can fail internally while other functions work fine.
• PossibleBulb issue affecting flasher behaviorA burned out bulb can sometimes cause faster-than-normal flashing on the working side.

What to do

1. Test the turn signals separately, since hazards and turn signals often share the same fuse and flasher relay.
2. Check the fuse box for a blown hazard/turn signal fuse and replace with the correct amperage.
3. Locate the flasher relay (check owner's manual or fuse box diagram) and try swapping with an identical relay if available.
4. Check all exterior bulbs related to turn signals and hazards for burnout, since a bad bulb can affect flash rate.
5. Listen for a clicking sound when pressing the hazard button, which indicates the switch and relay are functioning.
6. If there's no click and no lights at all, suspect the switch or fuse first.
7. Avoid driving without working hazards if you may need them in an emergency or breakdown.
8. Have a shop replace the flasher relay or switch if basic checks don't resolve it.

Tools and parts

• Fuse puller or pliers
• Replacement fuses

When to call a pro

If turn signals and hazards are both out, a shop can quickly test and replace the flasher relay, which is a common and inexpensive fix.

Safety