The car in your bay isn’t talking, and providing you with few clues as to what ails it. The schematics laid out on your workbench may as well be the undecipherable ramblings of a toddler for all the sense they make to you. The flow chart you’re using says something about measuring 5.0 volts on pin “A” of the sensor connector but you’re not sure why it should be 5.0 volts and not the 12.5 volts you measured at the battery. You remember something that instructor said at the electrical training class you attended a few months back about something called “voltage drop”. Would that explain why you’re reading the 5.0 volts on your meter?
You go back to the car and hook up for the next test the trouble tree is instructing you to do. You don’t know why you’re taking this test. And it isn’t the easiest connector in the world to get to. Maybe you can skip this one and move on to the next? For that matter, why don’t we just skip to the bottom and “replace with a known good component” to see what happens?
Your frustration is building. You’ve been at this for most of the day and still don’t see the light at the end of the tunnel.
Then you look across the shop at Bob. Bob thinks he’s just the greatest tech who ever lived. He loves doing electrical work, says it’s clean work and requires very little heavy lifting. And, as much as you hate to admit it, he’s pretty good at it. You’re betting he’d have this car fixed by now if he’d had pulled the ticket before you.
There are three areas you need to know you know before you’ll be as comfortable tackling electrical problems as Bob seems to be. First, you need to understand some basic electrical theory. Second, you need to understand how to read an electrical schematic. And third, you need to understand the voltage drop testing technique. In the May 2013 edition of the Trainer, we’ll focus on strengthening your electrical fundamentals foundation so you’ll have a solid base to build on. And we guarantee that if you study the basics enough to make them automatic in your thinking, you may even be better than Bob when tackling electrical gremlins in the future. Click this link to subscribe to Motor Age! http://bit.ly/MA_YT_freesub