Dashboard lights follow a colour convention that tells you most of what you need to know before identifying the specific symbol.
Red means stop
Red indicates something that can cause serious damage or is a safety risk. Pull over safely and switch off.
Oil pressure – the most urgent. Continuing to drive can destroy the engine within minutes. This is not the oil level light; it means pressure has been lost.
Coolant temperature. Overheating warps components expensively. Stop and let it cool before opening anything.
Brake system warning, which may indicate low fluid or a fault. Do not continue.
Charging system, meaning the battery is not being charged. You have limited time before the car stops.
Amber means investigate
Something needs attention and is not immediately dangerous. Drive gently and get it checked.
Engine management, which covers an enormous range from a loose fuel cap to a genuine fault. If it flashes rather than staying lit, that indicates a misfire that can damage the catalytic converter, and you should reduce speed and stop.
Tyre pressure, ABS, traction control, and various others.
Green and blue are information
Something is switched on. No action needed.
The general rule
Red now, amber soon. If unsure, stopping is always the safe choice.
And a light that comes on and goes off has still recorded a fault code, which a garage can read even after the light clears.