Quick answer: dashboard warning lights follow a traffic-light system. Red means a serious problem: stop safely as soon as you can. Amber or yellow means something needs checking soon. Green or blue lights just confirm that a system, such as your headlights or cruise control, is on. Your owner’s manual shows the exact symbols for your car.
Key Takeaways
- A red oil pressure, temperature or brake light means pull over and switch off the engine as soon as it is safe.
- A steady check engine light means book a diagnostic check. A flashing check engine light means reduce speed and get it checked right away.
- A battery light while driving usually points to the charging system (alternator or drive belt), not the battery itself.
Red Warning Lights: Stop Safely
Oil Pressure Warning (Oil Can Symbol)
This means the engine has lost oil pressure. Driving on can destroy the engine in minutes. Pull over, switch off the engine, wait a few minutes, then check the oil level on the dipstick. If the level is fine and the light stays on, do not drive the car: have it towed.
Engine Temperature Warning (Thermometer Symbol)
The engine is overheating. Stop and switch off the engine. Do not open the radiator or coolant cap while it is hot, because pressurized coolant can cause serious burns. Once it has cooled, check the coolant level and look for leaks.
Brake System Warning
This is usually a circle with an exclamation mark or the word BRAKE. First check that the parking brake is fully released. If the light stays on, the brake fluid may be low or there may be a fault in the brake system. Have it checked before driving further.
Battery / Charging Warning
A battery symbol lit while driving means the battery is not being charged, often because of a failed alternator or a broken drive belt. The car will run on battery power only for a short time, so switch off non-essential electrics and drive straight to a garage, or stop safely.
Airbag Warning
This means a fault in the airbag system, so the airbags may not deploy in a crash. The car can still be driven, but get it checked promptly.
Amber and Yellow Lights: Get It Checked Soon
Check Engine Light (Engine Outline)
This means the engine computer has detected a fault. A loose fuel cap, a sensor or an emissions problem are common causes. If the light is steady, book a diagnostic scan soon. If it is flashing, the engine is misfiring and can damage the catalytic converter: reduce speed and get it checked as soon as possible.
Tire Pressure Warning (TPMS)
A horseshoe shape with an exclamation mark means one or more tires are under-inflated. Check all four tire pressures when the tires are cold and inflate them to the figures on the driver’s door sticker.
ABS Warning
This means a fault in the anti-lock braking system. Your normal brakes should still work, but the wheels may lock under hard braking. Have it inspected soon.
Traction or Stability Control
If it flashes briefly while driving, the system is working, for example on a slippery road. If it stays on, there may be a fault, or the system may have been switched off.
Green and Blue Lights: Information Only
These lights confirm that a feature is on: headlights, high beams (usually blue), fog lights, turn signals or cruise control. They do not mean anything is wrong.
Frequently Asked Questions
Can I drive with the check engine light on?
If it is steady and the car drives normally, you can usually drive carefully to a garage for a diagnostic check. If it is flashing, or the car runs badly, reduce speed and get help as soon as possible.
Why do all the warning lights come on when I start the car?
This is a normal bulb check. The lights should go out within a few seconds after the engine starts. Any that stay on need attention.
How do I reset a warning light?
Fix the cause first. Many lights go out on their own once the fault is fixed. A check engine light can be cleared with a diagnostic scanner, but it will come back if the fault is still there.
