Bulb failure (exterior light) warning

One of the outside lamps — a headlamp, brake light, indicator, tail or number-plate lamp — has failed or its circuit has a fault. The car tells you that something is out, not always which one.

Yellow / amber

Not defined by regulation: a maker convention

What to do

Walk round the car with the lights, the indicators and the hazard lights on, and ask someone to watch the brake lights while you press the pedal. Have the failed bulb replaced without delay, as both Volkswagen and SEAT say.

Makes differ: what this light means on your car, the other colours it may use for the symbol and what the car wants you to do are set by the manufacturer, so your car's owner's manual is the authority.

Symbol: Light bulb with rays and an exclamation mark
Colour: Yellow / amber
Standard: None — a maker convention, described here from 3 makers: Volkswagen, SEAT, Hyundai

Where makes differ

Volkswagen and SEAT draw an amber bulb with an exclamation mark. Hyundai's manual has a separate LED headlight warning light for LED headlamp faults and reports other exterior light faults with the master warning light and a message.

Not defined by regulation: a maker convention

Neither US FMVSS 101 (Tables 1 and 2) nor UN Regulation No. 121 lists this light, so no rule fixes its symbol or its colour. What follows is what the makers cited below say; other makes, and other model years of the same make, may draw it differently.

Neither FMVSS 101 nor UN R121 lists a lamp-failure tell-tale.

Related lights a regulation does define

Turn signal indicatorTwo arrows pointing apart

Other yellow / amber maker lights

Diesel particulate filter (DPF) lightBox full of dots with a pipe at each end · maker convention AdBlue (DEF) warning lightLiquid container with a wavy fill line and a drop · also red · maker convention EPC (electronic power control) lightThe letters EPC · maker convention Lane assist (lane keeping) lightLane markings running away from you, dashed line in the middle · also green · maker convention Forward collision warning lightCar seen from behind with radar arcs around it · also red · maker convention Blind spot monitor lightTwo cars side by side with signal waves between them · maker convention Adaptive cruise control (ACC) lightSpeedometer dial with a needle · also green · maker convention Auto Hold lightThe words AUTO HOLD · also green · maker convention Power steering warning light (EPS)Steering wheel, sometimes with an exclamation mark · also red · maker convention Water in fuel light (diesel)Fuel pump with water drops beside it · maker convention Gearbox (transmission) warning lightCog wheel with an exclamation mark · maker convention Key not detected lightKey with a question mark · maker convention Hill descent control lightCar pointing down a slope · also green, red · maker convention Auto stop-start lightLetter A inside a circular arrow · also green · maker convention

All yellow / amber dashboard lights, regulated ones included

Sources

No regulation defines this light, so it is described from 3 carmakers' own manuals or owner pages, each fetched and checked on the date shown:

Volkswagen: Volkswagen UK — Bulb monitoring (amber lamp) — Check the operation of all exterior bulbs and have the defective bulb replaced without delay. checked 2026-09-24
SEAT: SEAT UK — Warning lights explained (Exterior lights) — When amber, check that all exterior lights are working; a failed bulb should be replaced by a retailer immediately. checked 2026-09-24
Hyundai: Hyundai owner's manual, 2026 Palisade (US) — Warning and indicator lights ((23) Master warning light; (24) LED headlight warning light) — The master warning light covers an exterior light malfunction; a separate LED headlight warning light lights or blinks for LED headlight faults. checked 2026-09-24

Written in our own words; the makers' pages cover their own models only.