What is an Engine Management Light?

03rd Feb 2022

By Daniel Hitchman

Engine management warning light

It's never ideal when something on your car goes wrong or develops a fault.

It's also unhelpful when a light appears on your dashboard that could be caused by a variety of things. One such example of that is the engine management light (EML), which is also known as the check engine light.

What does the engine management warning light mean?

In the majority of cases, the EML points towards an issue with the engine or exhaust system. It also depends on the way the light is displayed, because a solid light has a different meaning compared to one that's flashing.

Below, we explain what the different types of lights mean, what could be causing the EML to illuminate, and how it affects your MOT results.

What does each engine management light mean?

Volkswagen Polo GTI exhaust tip

Depending on the issue with your car, the EML in your car may present itself differently, as we've highlighted below.

As with any warning light, we recommend taking your car to your nearest Evans Halshaw retailer for a professional diagnosis.

Amber engine management light

This is the most common type of EML and is also the least severe.

Usually, you can keep on driving normally until you can get your car checked over by a professional.

Engine management light flashing

This is more severe than an amber light and is usually triggered by an issue affecting the car's performance, such as a misfire. You may notice a juddering sensation or a loss of power when this happens.

In some cases you can nurse the car to a safe place or your home, but we recommend pulling over and contacting a garage or recovery company for assistance.

Red engine management light

As you can imagine, the red light is the most severe type and means your car is unsafe to drive.

It's essential that you pull over as soon as it's safe to do so and contact a garage or recovery company for assistance.

What can cause the engine management light to come on?

MOT Technician inspecting a vehicle's engine bay

There are a variety of components fitted to your car that could cause the EML to illuminate if they're faulty, as we've outlined below.

Faulty Oxygen Sensor

The oxygen sensor is designed to keep your car's engine running efficiently by telling the ECU (the car's brain) how much unburnt oxygen is leaving through the exhaust.

If it's faulty, then the car can't operate efficiently, which in turn causes the EML to appear.

Faulty Ignition System (Petrol)

Petrol-powered cars rely on the ignition system to run the engine. You may have heard of components such as a spark plug or coil pack, which form part of the system.

If any part of the ignition system develops a fault, it'll cause the car to misfire and lose performance, and will therefore cause the EML to illuminate.

Damaged Catalytic Converter

The catalytic converter forms part of the exhaust system and is designed to reduce the harmful emissions created by your car's engine.

A broken or leaking catalytic converter is a major problem that needs rectifying as soon as possible.

Blocked Diesel Particulate Filter (Diesel)

The diesel particulate filter (DPF) is designed to prevent the soot produced by diesel engines from leaving the exhaust, which therefore reduces harmful emissions.

The causes of a blocked DPF, and what you can do to solve the issue, can be found in this useful blog.

Loose Fuel Cap

This is probably the most unlikely cause, but it's not unheard of.

If your fuel filler cap is loose or missing, then the vapours can escape from the tank. Reattach the fuel filler cap properly if it's insecure and the light should soon disappear.

Is an engine management light an MOT failure?

MOT Technician inspecting the underside of a MINI Hatchback

The engine management light is considered a major fault and will therefore result in your car failing its MOT if it remains illuminated.

It's understandable because if the light is illuminated then it's highly likely that your car is either unsafe or nowhere near as efficient as it should be.

Simply put, the issue causing the EML needs rectifying before it goes in for an MOT, or it'll fail.

How do I reset the engine management light?

Unfortunately, there's no quick or easy remedy for getting rid of the light if the problem hasn't been sorted on the car.

If the light remains after the issue has been fixed, then we would recommend taking the car to your nearest Evans Halshaw retailer, who will be able to clear the code for you.

Discover more motoring advice through Evans Halshaw

Like we said at the start, there's nothing ideal about a fault developing on your car, especially when there are several things that need checking in order to determine the issue.

With the advice and information above, we trust you'll have a clearer insight into the EML and what the causes and solutions are.

For more motoring advice, or general tips, then please head over to our blog section, which is frequently updated with fresh content.