Posts Tagged: automotive electrical repair
How To Diagnose Automotive Wiring Faults Like a Pro
How to Read an Auto Wiring Diagram and Find Electrical Problems Fast Quick Summary If you can read an auto wiring diagram and understand how a circuit is supposed to work, you can diagnose almost any electrical problem. Most wiring faults fall into three categories: 1) A short circuit, 2) An open circuit, or 3) Excessive resistance causing a voltage drop. The key is testing correctly—using proper back probing techniques, voltage drop testing under load, and continuity checks without damaging connectors. Done right, you protect sensitive modules and avoid creating … Read More
What Causes Car Battery Corrosion? Answers and Prevention Tips
The Real Cause of Battery Terminal Corrosion Quick Summary If you’ve ever opened your hood and found a white, blue, or green crust growing around your battery terminals, you’re not alone. In most cases, battery corrosion is caused by escaping sulfuric acid vapors reacting with the metals in the battery cable terminals. The vapors escape due to overcharging, undercharging, heat, or gaps between the battery case and the battery posts, most often in aging batteries. The good news is that battery terminal corrosion can usually be prevented with proper maintenance … Read More
How to Find What’s Draining Your Car
Step-by-Step Guide to Locate What’s Draining Your Car Battery Quick Summary If your battery keeps dying overnight or after sitting for a few days, you’re probably dealing with a parasitic battery drain. The good news is that you can find what’s draining your car battery with either a current-draw test or a voltage-drop test. In this guide, I’ll explain both methods, show you the tools I use, and reveal the most common causes of battery drain, including stuck relays, malfunctioning modules, glove box lights, aftermarket electronics, and charging system issues. … Read More
How to Test an Alternator With a Multimeter the Safe Way
How to test an alternator using a multimeter Quick Summary You can safely and accurately test an alternator with nothing more than a digital voltmeter—no special tools required. Never disconnect the battery while the engine is running, especially on modern vehicles. The correct method involves checking battery voltage at rest, monitoring charging voltage under load, and understanding how newer computer-controlled charging systems behave. Article Why Testing an Alternator the Wrong Way Can Destroy Electronics Over the years, I’ve seen plenty of well-meaning DIYers ruin perfectly good vehicles by using outdated … Read More