So What Does Auto Electrics and Diagnostics entail?
Many people get mistaken as to what is involved in diagnostics. Whether it be an engine fault, or a fault with another system on a vehicle, making the correct diagnosis is paramount to modern day vehicle repair. Many people are under the impression that we simply plug a diagnostic computer on to your vehicle and it tells us exactly what is wrong and what is required to repair it. If only it were that simple an auto electricians job would be far more hassle free.
A modern day ECU is only as smart as the programmer, and is only capable of giving a certain amount of information about any fault that may exist on your vehicle. So why do we plug cars onto the diagnostic machine? An electrical fault with a car can be caused by a huge number of different things. For some you may get a warning light, for others you may not, and for some you should get a warning light and still may not. If we are going to accurately repair your car then we need to know where the best place to start looking is. So lets say you have a fault with your engine control system for example, then we would plug our diagnostic machine in and try to extract as much information out of the ECU available to locate the area at fault so we can investigate.
Now the computer will give us a fault code that will have a description for the fault at hand, but it is not going to tell us what is causing that fault, only that it exists with a certain component / circuit. This is where diagnostics comes into it, the computer is not smart enough to know if it is a sensor fault, a wire broken or whether any other module is the cause. We have to investigate this and begin to test the various components, wires and circuits that are linked to the fault codes that are retrieved. We will also make use of live data feeds to help assist in the fault finding process, looking for anomalies in readings that are being fed back to the ECU as sometimes fault codes alone are just not enough.
Many voltage readings are taken, and many tests performed on the wiring looms using a multimeter and oscilloscope to help us work towards accurately diagnosing your fault. Although this may seem like a straight forward process it is not always the case. Over the years we have seen many faults that have had us looking for hours. With diagnostics things are not always what they seem, and we have seen many faults that have been caused by things that you would least expect. These are the most challenging and time consuming jobs that we have in.
Accurately diagnosing a fault with a car is the most important. We don't believe in just changing parts and hoping for a fix. We like to test things thoroughly and prove that a part is failing before we opt to replace it. This in turn saves the customer money and makes sure the job gets done correctly. And with the price of many replacement parts these days nobody wants to be replacing parts that are not needed.