Red · Important
Brake light bulb — out
The red rear-lamp icon with an exclamation mark warns that one of your brake-light bulbs is out. Traffic fine risk plus rear-collision risk when braking.
What this indicator means
Modern cars monitor current in the brake-light circuit. If a bulb burns out, circuit resistance drops sharply — the ECU logs it and turns on the indicator. On LED tail lights individual segments can fail while the lamp keeps glowing.
Common causes
- One of the three brake-light bulbs burnt out (most common)
- Oxidised socket or bulb base
- Blown brake-light circuit fuse
- Brake pedal switch fault
- Broken wire between the pedal and the rear lights
What to do as a driver
Have someone press the pedal, inspect all three rear lights. Found a dark one — turn ignition off, twist the bulb out, replace with the same type (P21W typical). LED brake-light modules cost $30–80 to replace.
Safety
Important: without a brake light rear-end collision risk rises. Fix before the next drive.