In my last blog, I compared Computerized Diagnostics to going to the doctor. This comparison hopefully explained the diagnostic procedure to where it’s easier to understand. Now I want to do that again and explain how more than one problem can give the same symptom.
In this example, let’s pretend you have a limp on your left leg. Now, remember trouble codes only give general explanations. Three months ago, you had a limp and I replaced your knee. This time, you set a code for your ankle. Both problems will give you the symptom of limp, but they are two totally different repairs.
On the car, it is the same. For example, we have all seen the check engine light flash on and off and the vehicle is shaking violently. This is usually caused by a misfire on one or more cylinders. Now a misfire is when a cylinder does not burn the fuel and does not help the engine run. This misfire can be caused by spark plugs not giving spark. Whether it’s a plug, plug wires, or coil. Also, if the fuel injector did not deliver fuel, this can cause a misfire. In a worst-case scenario, the engine itself could be bad causing it to misfire.
In this example, I am going to talk about something we all want down here in the south, Air Conditioning. There are several things that can fail that will cause the A/C not to cool. Is there a Freon leak? Did the A/C Compressor break internally or did a sensor fail causing you to be hot and sweaty in your car? All these problems are different repairs at different places.
Just remember, if your car had the same symptom last month, it does not mean it was the same problem. If you take it in to be repaired, find out what the problem is before assuming it was the same problem. It could be under warranty, or it could be a new problem causing the same symptom.
Many might wonder, “Why does it cost so much to correct a ‘check engine’ light?” In our last article, we looked at what car codes are and what a check engine light really means.
Since the engine light diagnostic process can be a bit technical, it can be described using a simple analogy that most all of us can relate to: Going to the doctor.
Going to the doctor when something is wrong with you, is like your check engine light coming on and getting it looked at. When the doctor asks you what is wrong or checks your vitals, that is similar to automotive technicians using a scan tool to retrieve a car code.
Let’s say you have pain in your left-hand index finger. If you use a cheap code reader, it will tell you your finger hurts on your left hand. If you use a scan tool, it will tell you that your index finger on your left hand hurts. This is similar to doctors using more advanced tests to diagnose your ailment. Doctors might think the problem can be fixed simply, with just a band-aid, if they don’t run all the tests.
Similarly, if you took your car code problem to an automotive parts house, they would likely say that the issue can be fixed with a simple part, without looking at all the factors. But, if you took your car to a certified technician upfront, they could diagnose the problem and correct the specific problem, and not just provide a temporary fix.
These are the basic diagnostic steps a doctor takes, when assessing your finger pain:
- The first step is the doctor would look at your finger to see if it is cut and decide if a band-aid will fix it.
- If it is not cut and not in the wrong position, then he must take an x-ray.
- If he does not see broken bones, then the doctor must use an MRI to check tendons and ligaments.
- If there is no problem found, he must check the nerves (wires) to your brain (computer).
- Now he must make sure all other components, nerves, fingers, blood flow, etc. are all correct. Once he determines that all other parts are good, then he will look at your brain (computer).
The problem with simple finger pain, is that it could be caused by a variety of issues, meaning that it could be overly complicated to fix it. This is also true when it comes to car codes and getting that check engine light to go away.
At White’s Automotive, every mechanic has undergone training to thoroughly understand and diagnose engine problems. The diagnostic problems could take anywhere from 15 minutes to 8 hours or more to complete. It may take one test or more to diagnose your vehicle and provide a viable solution.
Look for next month’s article from White’s Automotive Center, where they will look at the same system, but different problems.