Dashboard Warning Lights: What They Mean and What to Do
Dashboard warning lights are colour-coded: a red light usually means stop safely as soon as you can, while an amber or yellow light is a…
Dashboard warning lights are colour-coded: a red light usually means stop safely as soon as you can, while an amber or yellow light is a caution to get the car checked soon. Knowing which lights are urgent helps you avoid both breakdowns and unnecessary worry.
Key takeaways
- Red warning lights mean a serious problem; stop safely and seek help.
- Amber or yellow lights mean caution; the car needs checking soon, not necessarily immediately.
- The oil pressure and temperature lights are among the most urgent of all.
- An engine management light can be minor or serious, so it should always be diagnosed.
- If you are ever unsure, it is safer to stop and call for advice.
Red vs amber warning lights
The colour of a warning light tells you how urgent it is. Red lights warn of a serious fault that could risk your safety or cause damage, so you should pull over safely and stop. Amber or yellow lights are advisory, meaning the car can usually still be driven carefully but needs attention soon.
Green and blue lights are simply telling you a system is active, such as your headlights or indicators, and are nothing to worry about. When a red light appears while driving, treat it seriously and find a safe place to stop rather than carrying on.
The engine management light
The engine management light, often an amber engine symbol, signals that the car's computer has detected a fault somewhere in the engine or emissions system. It can be triggered by something minor like a sensor or loose fuel cap, or something more serious, so it always needs diagnosing.
If the light is steady and the car drives normally, you can usually continue carefully and book a check. If it is flashing, or the car is running roughly or losing power, reduce speed and get it looked at quickly. Our diagnostic equipment reads the stored fault codes to find the real cause.
Oil pressure and temperature warnings
The oil pressure light and the engine temperature warning are among the most urgent on the dashboard. Low oil pressure or an overheating engine can cause severe, expensive damage in a very short time, so both call for you to stop as soon as it is safe.
What to do
If the oil light comes on, stop and switch off the engine; running it with low oil pressure risks serious harm. If the temperature gauge climbs into the red or the warning shows, pull over and let the engine cool before checking coolant. In either case, don't keep driving in the hope it clears.
Battery and charging light
A red battery-shaped light usually means the charging system isn't working properly, often due to the alternator, drive belt or battery. It does not always mean the battery itself has failed, but it does mean the car may be running on stored charge that will eventually run out.
If this light stays on while driving, reduce your use of electrics and get the charging system checked promptly. We can test the battery, alternator and belt to find out exactly what is wrong. See our guide on battery testing and replacement if your car is also slow to start.
Brake, ABS and tyre pressure lights
The brake warning light can indicate something as simple as the handbrake being on, or as serious as low brake fluid or a fault, so never ignore it. The ABS light means the anti-lock system has a fault, and the TPMS light warns that a tyre is low on pressure.
- Brake light: check the handbrake is fully off; if it stays on, have the brakes and fluid checked.
- ABS light: normal braking usually still works, but the anti-lock function may not; get it diagnosed.
- TPMS light: check and adjust your tyre pressures, and look for a slow puncture.
Because braking is safety-critical, any persistent brake or ABS warning is worth checking quickly rather than leaving until your next service.
When to stop immediately vs book in
As a rule of thumb, stop as soon as it is safe for any red light, and especially for oil pressure, temperature or brake warnings. For most steady amber lights, you can usually drive carefully and book the car in within a few days for a proper check.
If a warning is accompanied by smoke, a strong smell, a loss of power, or unusual noises, treat it as urgent regardless of colour. When in doubt, it is always safer to stop and ask for advice than to keep going and risk a bigger problem.
Frequently asked questions
Is it safe to drive with the engine management light on?
If the light is steady and the car drives normally, you can usually drive carefully and book a diagnostic check. If it is flashing, or the car is misfiring, juddering or losing power, reduce speed and get it checked quickly, as continuing could damage the catalytic converter.
Why did a warning light come on then go off?
An intermittent light often points to an early or occasional fault that the car's computer has logged. Even if the light clears, the fault code is usually stored, so a diagnostic scan can reveal what triggered it before it becomes a recurring problem.
Can you tell me what a light means over the phone?
We can often give you initial guidance if you describe the colour, symbol and how the car is behaving. For anything red or safety-related, though, the safe advice is to stop and have it checked properly rather than guessing.
Seeing a warning light you're unsure about? Don't guess. Call Park Royal Tyre & Alignment Centre on 020 3886 2355, message us on WhatsApp at 07476 586 589, or book a check at our Park Royal workshop. We'll read the fault codes and tell you exactly what's going on.
24hr Emergency Mobile Tyre Service
Puncture repairs, new tyres, wheel balancing & battery jump-starts, fast response at home, work or roadside across West London.