The perplexity of electrical diagnostics

Basic principles of general fundamentals avoids confusion


Herein lies the difficulty. Even though the average person involved in maintenance can read this editorial and agree with it in principle, the average shop supervisor will still push and push and push a person to work faster on electrical problems, or rudely accuse them of wastefully using the schematics (read “tool”) the manufacturer provides.

If you put all of these factors together in proper context, you get a situation that makes you wonder why anything gets fixed at all. If not that, it creates an image of a situation that explains why it takes as long and costs as much as it does to solve electrical faults.

My purpose here is to get you to stop and ask yourself; Does it makes any sense that systems on vehicles that function using insanely simple concepts - literally hundreds of years old in some cases - should be so doggoned difficult to fix?

Until the trucking industry grabs the wheel at 9:00 and 3:00 o’clock position, assertively steers the discussion about this problem to a safe and productive location, and then applies the parking brake for the duration, nothing will change.

I have faith that all who read this will agree that electrical problems are the most costly and confusing, and that finding enough mechanics who have the moxie to become a “good electrical man” is next to impossible.

But I wonder if any will agree that the problem is one that is long past due for examination and one that if solved, could have the greatest impact on truck maintenance in the history of the industry. The manufacturers are not slowing down the electrification of the vehicles, but they didn’t invent, and they don’t own, the principles they use to build the trucks fleets operate.

Isn’t it reasonable that you are the ones who should be dictating to them how they will build them, rather than they being the ones who tell you what you have to accept?

I’m serious here. It really doesn’t have to be so difficult.

Dan Sullivan is a professional vehicle electrician and electrical trainer, member of TMC and the founder of Sullivan Training Systems - the only technician-owned training company dedicated solely to electrical training specifically for mechanics in the heavy equipment and heavy truck industries. He has more than 25 years experience as a mechanic and 20 years as a technical teacher. Since 1996, he has taught his streamlined diagnostic methods to more than 4,000 technicians employed by every major U.S. and European truck manufacturer. He is the author of Fundamental Electrical Troubleshooting, a 200-page practical electrical shopbook, and is the inventor of TESlite Voltmeter Leads - a tool that allows an instantaneous load test of wiring to locate corrosion with a digital voltmeter.

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