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The DIY Car Repair Owners Fear and Do Wrong The Most

Here's a great introduction to how to properly begin any repair involving the one automotive system most car owners fear and do wrong the most.
Conquer Your Car DIY Repair Fear

In earlier articles we've discussed one of the most common mistakes mechanics (and some service centers) make whenever working on a car with a problem that is not immediately self-evident: Firing the parts cannon hoping replacing an older component with a new one will solve a problem.

Related article: Common Car Maintenance Mistake Owners Make When Diagnosing Their Car's Engine Problems

DIY Repairs Without a Proper Diagnosis

That was the message underlying a recent Royalty Auto Service YouTube channel episode where the host demonstrates one aspect of how to tackle a repair that many car owners fear attempting and/or attempt in the wrong way: The electronic module in their vehicle's electronics system.

There's no doubt about it. The more electronics automakers put into cars, the more problems you can expect. In fact, there is no end in sight of just how many chip-stuffed modules will be designed in today's and tomorrow's cars. I believe that this will extend even further when redundancies for every system component will be heaped upon vehicles toward creating the first truly no-maintenance, throw-away, disposable cars of the future.

Related article: $5,600 Repair Bill for This Ford F-150 Owner's Tail Lamps

But I digress.

The point of the referenced YouTube video is that many of us are guilty of firing the parts cannon by replacing electronic control modules willy-nilly, hoping that will solve a car's electronic problems. This is especially true when it comes to something less visual than a mechanical problem and more mysterious to the novice DIY mechanic—present company included…at times.

In other words, replacing a module just because you know it is a link in the affected system and you suspect (i.e., "hope") it has "gone bad" is a poor way to solve a problem. It's a haphazard approach that will cost you needless dollars and cause delays.

However, that said, sometimes it is the module that fails or fails intermittently making a diagnosis more difficult.

How to Check a Module Before Deciding to Replace It

Follow along with the host as he talks about and demonstrates the most basic checks you should do on any suspect module―its power and ground specs.

In the video you will learn that checking suspect modules can be done with inexpensive test equipment (some of which you can make yourself) and a systems schematic detailing which modules are in what system so that you can make sense of the module(s), wires, and connections you should focus your diagnosis and repair on.

The value of this video is that it is a good start toward familiarizing yourself with working on your car's electrical system, while the host makes a good point of why some commercial pen-style lightbulb test probes you will find in any auto parts store will not suffice because they might not be rated for the voltage and current you really need to diagnose with.

 

My Recommendations for Learning From the Video:

  • Watch the video in its entirety without taking notes or worrying too much about some details that are not immediately clear to you.
  • Read this article titled "The $20 Car Battery Tester Will Save You Over $200" to understand what the host is referring to when he discusses "loads" on an electronic component or circuit.
  • Read this article titled "Car Battery Maintenance, Testing, and Replacement With This Ultimate Guide" to supplement the car battery tester article because many times, an electrical problem is tied to a weak car battery, and this is the first place you check with any electrical problem before messing with any components in your car's electrical system.
  • Watch this informative short video on making and using your own probe for a simple car circuit test.
  • Watch the video above a second time because now it should make more sense about what the host is demonstrating. Take notes to reinforce your learning.
  • Either make your own or buy a multi-bulb test light (similar to what the video host demonstrated) that works on a range of voltages.
  • Practice disconnecting some of the components in your vehicle's electrical system to gain familiarity with using a test probe under load and see how simple your car's electronic problems can be once you know how to trace down and test a problem. Be sure to start with something small and use your car repair manual for some additional guidance where they discuss checks but might not explain exactly how to do it. Your vehicle's electrical system schematic should be in the repair manual.

Here are a few useful articles related to your car's electronic systems:

Timothy Boyer is an automotive reporter based in Cincinnati. Experienced with early car restorations, he regularly restores older vehicles with engine modifications for improved performance. Follow Tim on Twitter at @TimBoyerWritesfor daily news and topics related to new and used cars and trucks.

COMING UP NEXT: 8 Situations When You Should Never Buy That Used Car

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