Generic Diagnostic Approach

One common problem among technicians is misdiagnosing. Doing so results in comebacks that can turn into a major problem, especially if there are too many of them. Not following a structured approach to the diagnosis of a system is one of the chief causes for a misdiagnosis. In this blog, we will discuss several ways to improve your accuracy at finding and diagnosing an issue.

System of thought

One of the best ways to combat misdiagnosing is to create a systematic approach to finding the problem. One such system can be found below:

1. Determine the system

2. Think about how it operates

3. Think about the problem

4. Generate a list of possible causes

5. Diagnose and inspect in a logical manner

Digging Deeper

Now that you've read the steps above. Lets dig a little deeper into each step.

1. Determine the system:

All systems are not the same, and treating them the same can quickly become a problem. Because each vehicle is equipped differently take some time to identify the system that you are working on.

2. Think about how it operates:

This step takes the information from step 1 and applies it to the system's operation. Because of the variety of parts and problems you could face, it is important to understand how the system you are looking at works. Try to take each part into mind and think about how they all work together.

3. Think about the problem:

At this point, you should be starting to find the part of the system that is defective. Focus on that area and try to discover what is causing the issue. More than likely you'll be able to find other parts of the system that are affecting what you are working on.

4. Generate a list of possible causes:

Most problems you diagnose will have more than one possible cause. Two common mistakes at this stage include approaching the issue with an incomplete list, and or adding items to the list that can't cause the problem.  An example of this would be adding the master cylinder to our list for a low brake pedal. Conventional master cylinders cannon cause a low brake pedal.

5. Diagnose and inspect in a logical manner

If steps 1-4 are done correctly this step should be simple. Steps 1 to 4 will allow you to generate a flowchart that will lead you to pinpointing which part of the system is causing the problem.

Understand your system

To put it more simply, understand the system you are working on. By knowing the system, you can identify all possible causes, and find out witch one is causing the problem. By sticking to this process religiously you'll find that you are misdiagnosing less and less. For more help and interaction with mechanics of all skill levels, join our facebook group "Mechanic Mafia" on Facebook. Just click the button below.


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