Check Engine Light
Check Engine Light

When your car developes a wiring or electrical problem or your Check Engine Light comes on it may not be as serious as it looks. Some faults do not cause the Check Engine Light to come on however a fault code or codes could exist in the computer (ECU) or sensor which can help diagnose the faulty component or wiring.

Our test equipment covers low voltage (9 volt to 30 volt) DC systems and can be used on cars, vans, lorries, motor bikes, quad bikes, boats, caravans,trailers and many more.

Since the late 1990's most motor vehicles have become more electronic with mini computers and sensors installed which control a lot of the functions such as engine spark timing, fuel injector pulses, automatic windscreen wipers etc etc. These controllers are linked to a central computer ie: ECU. This warns you of a problem by turning on the check engine light as shown above.

Vehicles are fitted with a diagnostic plug which a technician can plug an electronic tool which can reveal what caused the Check Engine Light to come on. Many garages do not have the necessary equipment to correctly diagnose the fault and simply replace components in the hope it will go away.

Often a garage may miss diagnose this as a faulty component which can prove costly to you especially the main computer (ECU) and may only resolve the problem short term. There could be several reasons for this warning light to come on.

Our testing can include motorcycles, quadbikes, motor boats, basically anything with 12 to 48 volt systems.


As a vehicle gets older, water and road salt ingress can cause corrosion in wires around connections which causes resistance to voltage. The computer (ECU) see this as a faulty component and therefore causes the Check Engine Light to warn you of a fault. With the correct equipment this type of fault can be detected and corrected making considerable savings to you.

Parasitic draw.

Is your battery going flat overnight or after a few days. Well thats when parasitic draw comes in. Its basically some circuit in the vehicle drawing current from the battery after everything is switched off. This problem can be quite difficult to find especially with modern cars that have multiple computers and sensors. Our tools can identify where the problem lies saving considerable time and money replaceing modules etc when it could be a simple wiring problem.

OEM Parts.

When a garage diagnosis results in new parts being fitted, often they will use non factory parts known as OEM parts. These may be cheaper than original parts however they may well be inferior or of less quality. This can therefore only be a short term fix and may be the cause of the Check Engine Light symptom. Perhaps you bought a second hand vehicle, you may not know its history or what new or second hand parts have been fitted to it.


Sometimes owners may fit additional equipment to the vehicle and not carry out the fitment correctly. It may work however there may be an underlying fault which only shows up later in life.


Did you know that modern vehicles can have up to ten keys registered for the vehicle. The computer (ECU) registers every key uniquely so you may not know when buying a vehicle if you received all the keys registered. We can see this information and deregister any keys not present. This will safeguard your vehicle from being stolen, usually, just after its purchase.

Buying a used vehicle.

It is always wise to take a vehicle technician with you who can check the vehicle over to reveal information about it that may not be visible to you. This information could affect your buying price.

Boats and fibreglass vehicles.

Boats and other fibreglass vehicles must provide a seperate lead for chassis ground. We can check easily power and ground issues with our equipment. This will save you time and expense trying to locate the fault. Remember diagnosis is a fixed fee - what you decide to do is upto you.


With the right diagnostic equipment all of the above and more can be detected and corrected saving you costly unnecessary repairs or replacement of expensive components. The fault codes may be historical and have never been cleared so these too can be reset.
Diagnosis of the vehicle is relatively inexpensive and should be the first call for action.

You might find this video interesting although its from the USA it applies around the world. I have had personal experience of this with my vehicle when it was recalled for airbag issues but the dealer reported a suspension issue. That was 4 years ago and 4 MOT's passed. !!

Please note this video has advertising links which have no benefit to us whatsoever. Worth watching

We offer a fixed cost at home diagnostic check of your vehicle.

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