What are the methods for checking electrical leakage in a car circuit?
2 Answers
Methods for checking electrical leakage in a car circuit are as follows: 1. Visual inspection: First, check the battery's inspection hole and the exterior of the battery to see if there is any leakage. 2. Multimeter measurement: Use a multimeter to measure the battery voltage and charging output to ensure they are normal. The normal voltage should be above 12V, and it should not drop below 10V after continuous discharge for 10 seconds. 3. Turn off devices: Turn off all electrical devices in the car, ensure the doors and trunk are locked, disconnect the negative terminal of the battery, wait for 20 minutes, then connect one end of a test light to the negative battery cable and the other end to the negative battery post. If the light turns on, it indicates that electrical devices or circuits are still leaking electricity.
Oh, when it comes to checking for parasitic battery drain in a car's electrical system, I feel quite experienced. The key is to use a multimeter to measure the static current—that is, the current at the battery terminals when the car is parked, the engine is off, and all devices are turned off. Normally, it should be around 30 milliamps; if it exceeds 50 milliamps, it indicates a parasitic drain issue. At this point, you can pull out the fuses in the fuse box one by one and observe the current changes. When removing a specific fuse causes a sudden drop in current, you've found the source of the drain—common culprits include the anti-theft system, audio system, or OBD port, which may be quietly consuming power. Don’t forget to check for damaged wiring harnesses causing shorts or corroded battery terminals. These small details are easy to overlook but can lead to major problems. My personal advice is to record the current values before and after testing, and avoid hastily disassembling components to prevent misjudgment.
