Lights

Third (center high-mount) brake light isn't working

The center brake light mounted above the rear window or on the trunk failing is usually a burned out bulb or LED strip failure, separate from the two main brake lights.

Difficulty
Moderate
Time
20–45 minutes
DIY cost
$15–$60
Pro cost
$60–$200

Symptoms

  • Center brake light stays dark when braking
  • Both side brake lights work normally
  • LED strip type light may have some segments lit and others dark
  • Noticed via reflection in a vehicle behind you or a walk-around check

Likely causes

  • CommonBurned out bulb (on incandescent third brake lights)Older vehicles use a standard bulb for the third brake light that can burn out.
  • CommonFailed LED strip or driver (on LED third brake lights)Most modern vehicles use an LED strip, which can fail partially or completely.
  • PossibleBlown fuse for the third brake lightThis light may be on its own fuse separate from the main brake lights.
  • PossibleWater intrusion into the mounting areaThird brake lights mounted on the trunk or spoiler can develop leaks at the mounting points.

What to do

  1. Have someone press the brake pedal while you check the third brake light specifically.
  2. Check the fuse box for a blown fuse related to the third brake light and replace with the correct amperage.
  3. Access the light (usually from inside the trunk or through a rear interior panel) to check the bulb or LED strip.
  4. For incandescent bulbs, inspect for a broken filament and replace as needed.
  5. For LED units, note if it's a full failure or partial segment failure, which affects whether the whole unit needs replacing.
  6. Check the mounting area and connector for any signs of water intrusion.
  7. Test the light again after any bulb replacement or connector cleaning.
  8. Have a shop replace the entire LED unit if individual segments can't be repaired and the whole assembly needs replacement.

Tools and parts

  • Screwdriver or trim tool
  • Fuse puller or pliers
Third brake light bulb or LED assemblySearch: “third brake light assembly for [your car make model year]”

When to call a pro

If the third brake light is an LED strip with partial failure, a shop can advise whether a driver module replacement is possible or if the whole unit needs swapping.

Safety

Use caution

A non-working brake light, even the center one, reduces your visibility to traffic behind you; fix this promptly.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.