Dashboard Warning Lights Explained
A light has come on and you want to know how worried to be. Find the symbol below for a plain-English guide: what it means, whether you can keep driving, what you can check yourself and roughly what the fix costs in Ireland and the UK.
What the colours on your dashboard mean
RedA serious fault or a safety warning. Stop as soon as it is safe and find out why.
Amber or yellowSomething needs attention soon. Most cars can be driven carefully to a garage.
Green or blueInformation only: a system is switched on, such as headlights or lane assist.
Stop driving9
Pull in when it is safe and switch off. Driving on risks your safety or serious damage.
Battery Warning Light
Your car's electrical charging system has stopped supplying power to keep the battery topped up.
Stop driving
Brake Warning Light
A red brake light indicates that your handbrake is engaged, your brake fluid is low, or the hydraulic braking system has failed.
Stop driving
Coolant Temperature Warning Light
Your engine coolant has reached a dangerously high temperature or the coolant level has dropped too low.
Stop driving
Door or Boot Open Warning Light
This light means your car detects that at least one door, the boot or the bonnet is not fully latched.
Stop driving
Electronic Throttle Control (ETC) Warning Light
The electronic throttle control light means the computer has detected a fault in the drive-by-wire accelerator system.
Stop driving
Gearbox Temperature Warning Light
Your gearbox oil is dangerously hot and can no longer protect the internal components.
Stop driving
Oil Pressure Warning Light
Your engine does not have enough oil pressure to protect its moving metal parts.
Stop driving
Power Steering (EPS) Warning Light
Your car has detected a fault in its power steering assistance system.
Stop driving
Turtle Light (Reduced Power) in a Hybrid or EV
The car has entered a protective reduced-power mode because of an electrical or thermal fault in the high-voltage drive system.
Stop drivingHybrid & EV
Service soon15
The car can usually be driven for now, but book it in soon before it gets worse.
ABS Warning Light
The anti-lock braking system has detected a fault and shut itself off to prevent unpredictable braking.
Service soon
Airbag (SRS) Warning Light
The airbag warning light means the supplemental restraint system has found a fault and switched itself off.
Service soon
Blind Spot Monitor Warning Light
The blind spot monitoring system has detected an electrical fault or its radar sensors are blocked.
Service soon
Bulb Failure Warning Light
A bulb failure warning light means the car has detected an issue with an exterior light, such as a blown filament.
Service soon
Check Hybrid / EV System Warning Light
A fault has been detected in your car's high-voltage electrical drive system or its cooling setup.
Service soonHybrid & EV
DPF Warning Light
Your diesel particulate filter is filling with soot and needs to clean itself through heat.
Service soon
Engine Management Light (Check Engine)
Your car computer has detected a problem with the engine, fuel system, or exhaust emissions.
Service soon
Glow Plug Warning Light
The coiled spring symbol means your diesel pre-heaters or engine management system have detected an electrical or operating fault.
Service soon
Immobiliser (Security) Warning Light
Your car does not recognise the security code from your key or key fob.
Service soon
Lane Departure Warning Light
A lane departure light means your car is crossing road markings without indicating or the detection camera is blocked.
Service soon
Low Fuel Warning Light
The low fuel light means your tank is down to its final reserve of petrol or diesel.
Service soon
Reduced Engine Power Warning Light
Your car computer has detected a fault and switched into a protective limp mode to prevent severe engine damage.
Service soon
Seatbelt Warning Light
A seatbelt is unfastened or the car thinks someone is sitting in a seat without their belt on.
Service soon
Traction Control (ESP) Warning Light
A solid light means the electronic stability and traction system is switched off or faulty.
Service soon
Tyre Pressure Warning Light (TPMS)
This warning means at least one of your tyres has lost air pressure or a sensor has failed.
Service soon
Safe to drive1
A minor issue with no safety risk. Sort it out when it suits you.
Which warning lights fail the NCT or MOT?
A warning light that stays on after the engine starts, under the rules of the National Car Test in Ireland (NCT) and the MOT in the UK. Get these fixed before your test.
- Airbag / SRS
- NCT
- Fail
- MOT
- Fail
- ABS
- NCT
- Fail
- MOT
- Fail
- Brake system (!)
- NCT
- Fail
- MOT
- Fail
- ESP / ESC / traction control
- NCT
- Fail
- MOT
- Fail
- Power steering (EPS)
- NCT
- Fail
- MOT
- Fail
- Tyre pressure (TPMS)
- NCT
- Fail
- MOT
- Fail (cars first used from 2012)
- Engine management light
- NCT
- Advisory on its own - fails if emissions are over the limit
- MOT
- Fail
On the MOT the engine light must also come on briefly when you switch on the ignition, so a removed or covered bulb fails too. Rules change, so if in doubt, ask your test centre.
Outside Ireland and the UK? Check the regulations of your own country or state before going for a vehicle test.
Can't find your light, or seeing more than one?
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