Engine warning light: what should you do and when should you worry?

Has an orange engine-shaped warning light appeared on your dashboard? This light can indicate several types of issues, from an emissions system fault to a more serious engine problem.

The right approach is not to ignore it, but to assess how urgent it may be. At Garage David Queffelec, located in Quimper in the Moulin Vert district, we explain what to do next.

Why does the engine warning light come on?

Modern vehicles have many electronic sensors that monitor engine operation and related systems.

When a fault is detected, the engine control unit may store an error code and switch on the engine warning light. Different systems may be involved, including:

• Fuel injection.
• Ignition system on petrol engines.
• Engine sensors.
• Emissions control systems.
• Air intake system.
• Other electronic engine management components.

The warning light alone does not tell you exactly which part is causing the problem.

What should you do if the orange engine warning light stays on?

A steady orange engine warning light usually means the vehicle should be checked.

If the car seems to run normally, with no unusual noises, loss of power or other warnings, consult the vehicle manual and contact a professional as soon as possible for advice.

Avoid hard acceleration and long trips until the cause of the problem has been identified.

Important: a steady warning light does not automatically mean it is safe to keep driving indefinitely.

If the orange engine warning light flashes: be careful

A flashing engine warning light can indicate a more serious fault, such as engine misfires that may damage the emissions system.

In that case:

1. Reduce engine load immediately.

2. Stop as soon as it is safe to do so.

3. Switch off the engine.

4. Follow the manufacturer’s instructions and contact roadside assistance if necessary.

Do not continue driving if the light keeps flashing.

Likewise, if a red oil pressure warning light, an overheating warning or a message instructing you to stop the engine appears, stop the vehicle safely and seek assistance.

What is an electronic diagnostic?

An electronic diagnostic allows a technician to read the vehicle’s control units and retrieve stored fault codes. The information can then be analysed and followed by additional checks to identify the actual cause of the issue.

This process helps to:

• Identify the system involved.
• Read stored fault codes.
• Check live operating data.
• Look for the real cause of the fault.
• Determine the appropriate repair.

A fault code does not always point directly to the exact part that needs replacing.

A proper diagnosis requires data interpretation along with mechanical or electrical verification.

Why should you avoid clearing the warning light yourself?

Some scan tools can erase fault codes from a vehicle. However, making the light disappear does not mean the problem has been fixed.

Clearing the code may temporarily hide the fault and remove useful information needed for diagnosis. For that reason, it is better to identify the cause before resetting anything.

If your engine warning light stays on or your car does not feel right, Garage David Queffelec can carry out an electronic diagnostic on many makes and models.

Visit us at 45 bis route de Locronan, 29000 Quimper.