“How to Check Engine Warning Lights” is one of the most useful basic skills a driver can have — that small orange engine icon on your dashboard is your car’s way of flagging that something in the engine or emissions system needs attention, and understanding what it is telling you is easier than most drivers think. Knowing how to read it can save you from a breakdown on Sheikh Zayed Road, or from paying for repairs you did not need.
This guide walks you through what the check engine light means, how to tell a serious fault from a minor one, the simple checks you can do yourself, and when to head straight to a workshop in the UAE.
Quick Answer
To check engine warning lights: start the car and watch the dashboard — all warning lights should flash on briefly, then go out. If the check engine light stays on (solid), note whether the car drives normally; you can usually continue carefully and book a diagnosis soon. If it flashes, or comes on together with overheating, strange noises, or loss of power, pull over safely and switch off — a flashing light often signals a fault that can damage the engine or catalytic converter. For a precise answer, a workshop can read the fault code with a diagnostic scanner in minutes.
How to Check Engine Warning Lights: The Basics
Modern cars monitor the engine constantly through sensors and a computer called the engine control unit (ECU). When a sensor reading falls outside the expected range, the ECU stores a fault code and switches on the check engine light. The light itself does not tell you the exact fault — it is a prompt to investigate further.
The first and simplest check is the bulb test: turn the ignition to the “on” position without starting the engine. Every warning light on the cluster should illuminate for a few seconds, including the check engine light. This confirms the bulb works — a light that never comes on at all could mean someone has tampered with it, which is worth knowing before buying a used car.
Solid vs Flashing: What the Behaviour Means
| Light behaviour | What it usually means | What to do |
|---|---|---|
| Solid (steady) light | A fault is logged but the engine is running within safe limits — e.g. an emissions sensor or a loose fuel cap | Drive gently, avoid hard acceleration, book a diagnostic check soon |
| Flashing light | An active fault that can cause serious damage — commonly engine misfires | Slow down, pull over safely, switch off, call for assistance |
| Light that comes and goes | An intermittent fault, such as a sensor reading on the edge of its range | Note when it appears (cold start, highway, traffic) and mention it at the workshop |
| Light plus overheating gauge | Possible cooling system failure alongside the engine fault | Stop the car — overheating can destroy an engine in minutes; see our guide on common causes of car overheating |
Step-by-Step: Checking the Light Yourself
- Do the ignition bulb test. Key on, engine off: confirm the check engine light appears and then goes out after starting. If it never lights up, mention it to a mechanic — a dead bulb hides faults.
- Note the colour and behaviour. Amber or orange means “check soon”; red (on some cars the engine warning appears red) means stop. Flashing always means stop.
- Check the obvious first. A loose or cracked fuel filler cap is a classic cause — tighten it until it clicks and the light may clear after a few drives. Also glance at the temperature gauge, oil pressure light, and coolant level.
- Observe how the car behaves. Rough idling, hesitation, loss of power, or unusual smells narrow things down. Write down what you notice — it helps the technician enormously.
- Read the fault code if you can. An OBD-II Bluetooth scanner plugs into the diagnostic port (usually under the dashboard on the driver’s side) and pairs with a phone app to show the stored code, such as P0301. Affordable scanners are widely available in the UAE, and the code gives you — and the workshop — a concrete starting point.
- Get a professional diagnosis. A code points to a circuit or system, not a guaranteed failed part. A good technician confirms the fault with live data before replacing anything, which is how you avoid paying for parts you did not need.
Engine warnings are just one part of the picture — our guide to what different dashboard warning lights mean covers the rest of the dashboard.
Common Reasons the Check Engine Light Comes On
- Loose or faulty fuel cap — lets fuel vapour escape and triggers an emissions fault; often the cheapest fix there is.
- Oxygen sensor failure — the sensor that measures exhaust gases wears out, hurting fuel economy and emissions.
- Spark plugs or ignition coils — worn plugs cause misfires, rough running, and a flashing light if severe.
- Mass airflow sensor — a dirty or failed sensor confuses the fuel mixture, causing stalling or hesitation.
- Catalytic converter problems — often a downstream effect of driving too long with misfires or a rich fuel mixture.
- EVAP system leaks — small vapour leaks in the fuel system are common and usually minor, but they still light the lamp.
- Low battery voltage — a weak battery can trigger spurious sensor codes; if the car also cranks slowly, read our guide to car battery problems and warning signs.
None of these can be confirmed from the light alone — the fault code and a proper diagnosis are what turn a guess into an answer.
When Is It Safe to Keep Driving?
Use this simple rule of thumb: if the light is solid, the gauges read normal, and the car drives as usual, you can generally continue your journey and book a workshop visit within a few days. Ease off the accelerator, avoid towing or heavy loads, and do not take a long desert trip with an unresolved light.
Stop driving and switch off if the light is flashing, the temperature gauge climbs into the red, the oil pressure light comes on, you hear knocking or loud rattling, or the car loses power suddenly. Continuing to drive in these situations can turn a moderate repair into an engine replacement. If the car will not restart afterwards, our checklist on what to check when your car will not start can help.
Getting a Diagnosis in the UAE
Almost every independent workshop and all agency service centres in the UAE can read fault codes — a basic scan typically takes a few minutes. Ask what the code is and what it means before authorising any repair; a reputable workshop will explain the diagnosis rather than just quoting parts.
Keep in mind that an illuminated check engine light is also flagged during the mandatory vehicle inspection tied to UAE vehicle registration renewal, so resolving it before your test appointment saves a failed visit. Driving a car with a known serious fault can also carry penalties — see the UAE traffic fines guide. For keeping on top of all of this, the complete vehicle inspection and maintenance guide puts engine checks in a full routine, and RTA’s website lists official vehicle testing centres in Dubai.
Frequently Asked Questions (FAQs)
Can I check engine warning lights without a scanner?
Yes — partly. The bulb test, the colour and behaviour of the light, the gauges, and how the car drives tell you whether the situation is urgent. What you cannot do without a scanner is read the exact fault code. Many workshops in the UAE will read the code for a small fee or free with a service.
Will the check engine light reset itself?
Sometimes. If the fault was temporary — like a loose fuel cap you have since tightened — the light may go out after several drive cycles. But the fault code usually stays stored in the ECU’s memory, so a scan can still reveal what happened. Do not assume a cleared light means a fixed problem; get it checked if it returns.
Is a flashing check engine light an emergency?
Treat it as one. A flashing light typically indicates an active misfire that can overheat and destroy the catalytic converter, and in some cases damage the engine itself. Slow down, pull over where safe, and switch off. Call roadside assistance rather than driving on.
Can a weak battery trigger the check engine light?
Yes. Low voltage during cranking can confuse sensors and log fault codes that have nothing to do with the engine itself. If your battery is more than three years old or the engine cranks slowly, test the battery first — it is a cheap fix compared to chasing phantom sensor faults.
How much does an engine diagnostic check cost in the UAE?
Prices vary by workshop and emirate, but a basic OBD scan at an independent garage is typically inexpensive — often bundled free with a service — while agency service centres charge more. Always ask for the fault code and an explanation before approving repairs. Check official portals rather than relying on any single quoted figure you see online.
The Bottom Line
Knowing how to check engine warning lights comes down to three habits: watch the dashboard during the bulb test, learn the difference between a solid light (book a check soon) and a flashing one (stop now), and never ignore a light that keeps coming back. A quick diagnostic scan turns worry into information, and in most cases the fix is far smaller than drivers fear. Pair this with the rest of your dashboard knowledge and regular maintenance, and few car problems will catch you by surprise.
Last Updated: 8 October 2026
About the author: Zaviyar Sultan is a UAE-focused writer at Asandada24, covering driving, visas, banking, insurance and everyday UAE life. His guides are researched from official UAE government and regulator sources and updated regularly.
Asandada24 is an independent informational website, not affiliated with the UAE government or any agency mentioned; content is general information only, not legal, immigration or financial advice; verify critical details with official sources before acting.