Airbag warning light
A malfunction in the airbag system. UN R121 allows the tell-tale in yellow, red or both, and says that if one tell-tale reports airbag faults (front and side), it must use this symbol (note 7). FMVSS 101 names the air bag malfunction telltale among those that must take over a shared display space (S5.5.5).
Yellow / amberRed
What to do
Have the airbag system checked promptly: while this lamp stays on, the system is reporting that it may not work as designed in a crash. It normally lights for a few seconds at start-up as a check and then goes out; if it does not come on at all at start-up, that also needs checking.
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
- Seated person facing a round airbag
- Colour
- Yellow / amber or Red
What the colour means
Yellow / amber — “caution”
The same colour code (Directive 2009/80/EC, Annex I, 2.1.4) gives “amber: caution”. FMVSS 101 and UN R121 write the colour as “yellow”; it is the colour both tables give to malfunction telltales such as ABS, stability control and low tyre pressure.
Red — “danger”
The colour code that UN R121 points to (ISO 2575, paragraph 5) is sold, not published. The EU wrote it into law for two- and three-wheel vehicles in Directive 2009/80/EC, Annex I, 2.1.4: “red: danger”. FMVSS 101 does not define colour meanings, but S5.5.6(b) says a telltale for which red is required must not be cancelable while its underlying condition exists, and note 4 to Table 1 allows red to be red-orange.
Where the regulations list it
| Rule | Row | Colour it sets |
|---|---|---|
| UN R121 | Table, item 22 “Airbag malfunction” — tell-tale | yellow and/or red |
| FMVSS 101 | S5.5.2 and S5.5.5 — “air bag malfunction” telltale | no colour required |
UN R121: Cars (category M) and light goods vehicles (N1) type-approved under the UN 1958 Agreement, which includes the EU, UK and Japan (para 1). Its table gives the symbol and colour of each tell-tale; note 2 says the symbols are substantially identical to those of ISO 2575:2004. FMVSS 101: Passenger cars, multipurpose passenger vehicles, trucks and buses sold in the US (S3). Table 1 gives the symbol or words and, where one is required, the colour of each telltale; Table 2 lists identifiers with no colour requirement.
Good to know
- FMVSS 101 S5.3.1(e): a telltale may light during a bulb check — that is why most lamps flash on briefly when you switch on.
Other yellow / amber lights
Other red lights
Sources
- EUR-Lex — UN Regulation No. 121 (01 series), Official Journal of the EU L 5, 8 January 2016: table 'Symbols, their illumination and colours' — checked 2026-09-23
- eCFR — 49 CFR 571.101, Standard No. 101; Controls and displays (current text) — checked 2026-09-23
- Directive 2009/80/EC, Annex I, point 2.1.4 — the tell-tale colour meanings as written into EU law (for two- and three-wheel vehicles) — checked 2026-09-23
Meanings are written in our own words from these public texts, not quoted from ISO 2575, and were checked on the date shown.