Car Engine Diagnostic Test

Book in for a car diagnostics fault code report at Kwik Fit Plus centres

On-board diagnostic check services are available at most Kwik Fit centres but you can now book online at any of our Kwik Fit Plus centres nationwide.

To book and find your nearest Kwik Fit Plus centre offering on-board diagnostics, please enter your vehicle registration below and click 'Search'.

What is a diagnostics fault code check?

When a car warning light illuminates on your dashboard or an error message or code appears, a car diagnostics check or fault code check can help identify the problem before more serious damage occurs.

Electric Control Units (ECUs)

Most modern vehicles today contain a network of on-board computers known as Electronic or Engine Control Units (ECUs) which continually monitor the performance of the vehicle and can self-diagnose faults. These are also sometimes referred to as ‘Engine Management Systems’ (EMS), ‘Engine Control Module’ (ECM) and ‘Electronic Control Modules’ (ECM).

Sensors all around the vehicle report back to the ECU if there are problems such as low fluid levels or increased engine temperature. When an issue is identified the ECU generates an error code. The relevant dashboard warning lights will then be displayed. These codes can be meaningless without the proper diagnostic code reader. At Kwik Fit, we use Bosch OBD II scanners to read the codes and find out more specific information about the nature of the problem.

There are hundreds of potential OBD2 error codes that can only be read by specialist on-board diagnostic fault code readers. While a warning light may display on the dashboard alerting you to an issue, an on-board diagnostics fault code check is required to start to understand the issue and determine if a more in-depth diagnostic test with a specialist technician is required.

The Bosch OBD II diagnostic equipment can also be used to reset service lights, test and adjust braking systems where an electronic handbrake is present, and adjust headlamp levels. For more information, contact your local Kwik Fit centre.

What are dashboard warning lights?

Dashboard warning lights are indicators on the dashboard of a vehicle that alert the driver of a potential problem or malfunction. They can range from simple reminders, such as low fuel or seat belt not fastened, to critical warnings, such as engine overheating, oil issues, or brake failure.

For a list of the more common dashboard warning lights and what they look like, visit our What Do Your Dashboard Warning Lights Mean? page.

Check Engine Light

One of the most critical engine warning lights you might see on your dashboard is the check engine light. Also known as the ‘engine malfunction light’ or, simply ‘the yellow engine light’, this symbol is a crucial indicator of your engine’s health. It is important to note that this light isn’t always yellow; in some vehicles, this light can show as a dull amber or a bright orange too.

If your check engine light is on, it’s important that a technician inspects your vehicle as soon as possible before further, more serious damage is caused to your car engine, especially if your check engine light is flashing as this usually indicates a serious problem or emergency.

In order to diagnose a check engine light fault, an OBD2 scanner must be used to find out where the issue lies. At Kwik Fit, we can read your check engine light fault codes using our Bosch OBD II diagnostic equipment to provide a full explanation of the issue. Our fully-trained technicians can then suggest any necessary repairs that may be required to get you back on the road and rectify the error. So, there’s no need to pay vehicle dealership prices to diagnose your check engine light issue. If the problem can be fixed, this will reset the check engine light.

For more information read our blog ''Everything You Need to Know About the Check Engine Light'.

Check Engine Light

On-board diagnostics for your vehicle’s make & model

Not sure what a specific BMW fault code means on your display? Has the check engine light come on in your Ford? No matter the manufacturer, by quickly plugging in our OBD2 fault code scanner to your ECU, we can read the fault codes displayed by all major vehicle makes and models including Vauxhall, Audi, Mercedes and Volkswagen to name a few.

Our diagnostic technicians are on hand to explain and interpret the fault codes and give advice on any remedial work required to fix the problem before it becomes serious.

What does a full car diagnostic include?

On-board diagnostics tests are incredibly useful when it comes to ‘listening’ to your car. Typically, a full on-board diagnostic test of your vehicle can provide vital information about the following things:

  • Engine management issues
  • Transmission problems
  • Any faults with your ignition coils such as firing failure or low/high rpm levels
  • Throttle performance
  • Exhaust quality
  • Brake health
  • Engine coolant levels
  • How well the fuel injection system is performing
  • Ignition timing
  • And so much more.

While on-board diagnostic tests are primarily geared towards the engine, depending on the vehicle, information about additional features such as the lights, tyres, and comfort controls can be gathered as well.

How much does a diagnostic scan cost for a car?

How much it costs to get on-board diagnostic tests for your vehicle depends on a number of factors such as where you get it done and the car model. Some models require more sophisticated equipment than others, while unique vehicles such as sports cars may need their own diagnostic equipment entirely.

On average, the cost of an on-board diagnostic test is between £50 and £100. In order to mitigate costs, it is recommended that you keep up with your vehicle maintenance and get regular diagnostic tests to avoid any unexpected major issues.

Book an on-board diagnostic fault code check

You can now book a diagnostic fault code check online at any of our Kwik Fit Plus centres nationwide where our trained staff are on hand to scan the fault codes being displayed on the OBD reader and provide help and advice to resolve any issues found.

If a warning light or fault code has appeared on your vehicle dashboard, Kwik Fit can help identify and troubleshoot potential issues using our on-board diagnostics equipment, otherwise known as an OBD2 scanner.

Please Note: Kwik Fit Plus offers a car diagnostic check for £39.95 If a warning light or fault code has appeared on your vehicle dashboard, Kwik Fit can help identify and troubleshoot potential issues using our on-board diagnostics equipment, otherwise known as an OBD2 scanner.

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