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Car lights & visibility

Every lamp on your car, explained: headlights, daytime running lights, indicators, brake, tail, reverse, fog and plate lamps. Tap the interactive diagram, learn the bulb types, and run a two-minute walk-around check.

Lamps explained
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Bulb types
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Check items
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Why light maintenance matters

Your lights are your only way to be seen and the road’s only illumination at night. A single dead bulb can make you invisible in rain, fog or darkness, and is a common reason for roadside stops and failed inspections.

  • A two-minute walk-around check every week prevents most problems.
  • Replace bulbs in pairs — the other side is usually near the end of its life.
  • Never touch the glass of a new bulb with your fingers; oil makes it fail quickly.
  • Cloudy lenses cut up to 50% of light output — clean or restore them.

A quick fault-finder

One light not working

Most likely a bulb (or its socket). Swap the bulb with the working side to confirm, check the fuse, then the relay and wiring.

Both sides dead

A fuse or relay is the usual cause — or the switch (brake switch, reverse switch). Check the fuse box first.

Fast-flashing indicator

Classic sign of one bulb burned out on that side. Check the bulb, then the flasher relay if both are fine.

Dim headlights

Faded lenses, old bulbs or a weak charging system. Clean the lens, test voltage at the bulb, and check the battery.

FAQ

Dull or yellowed lenses, old bulbs, a weak charging system or a dirty ground wire. Clean the lenses, check voltage at the bulb (about 12.6 V+ with the engine off), and replace bulbs in pairs.
Check the owner manual or the bulb base. Common types: H4 (dual low/high), H7 (single), H11, 9005/9006, W5W (side/parking), P21W (brake/tail), PY21W (indicator amber), C5W (plate light). LED retrofits are not road-legal on all cars.
A faster flash usually means one bulb is burned out on that side. Some cars also show a fast blink for a bad LED or a relay issue. Check the bulb first.
Yes — a headlight restoration kit (sanding + polish + UV sealant) works well. The lens must be re-sealed, otherwise it yellows again quickly.
A full walk-around every week takes two minutes: low/high beam, indicators both sides, brake, reverse, fog, plate and interior lights. Have someone help with the brake lights.
No. Daytime running lights are dim by design and do not light the road. Always switch your real headlights on in the dark, rain or fog.

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