How to Determine Automotive Circuit Faults?
2 Answers
Automotive circuit fault diagnosis methods are as follows: 1. Sound detection method involves checking faults by listening to the instantaneous operational sounds of certain electrical assemblies. 2. Test lamp inspection method - With increasing electronic devices in modern vehicles, the traditional spark test method should be abandoned in favor of test lamp inspection. 3. Short-circuit inspection method involves directly powering electrical components with wires. For example, if the starter doesn't rotate, you can short-circuit the 'battery' terminal and 'starter' terminal of the starter relay with a wire. 4. Sectional inspection method: For faults in certain long circuits of vehicles, divide the circuit into sections and use the 'test lamp inspection' method to locate the faulty section.
As someone who enjoys tinkering with cars, diagnosing electrical circuit issues should start with the basics. First, visually inspect the wiring for any obvious signs of peeling or scorching, especially around connectors where poor contact is common. Then, use a multimeter to check voltages—for example, the battery voltage should stay around 12 volts; if it drops below 10 volts, the alternator might be the issue. Next, inspect the fuse box for any blown fuses and try replacing them with new ones. If the headlights flicker or the engine struggles to start, focus on the starter-related circuits, disconnecting connections step by step to observe symptom changes. Don’t forget safety: turn off all electrical devices and wear insulated gloves before working to prevent electric shock. Regularly monitor wire aging, especially in humid seasons when corrosion increases short-circuit risks—treating connectors with anti-rust spray periodically can extend their lifespan.
