How to Check if the Battery is Leaking?
3 Answers
To check if the battery is leaking, follow these steps: 1. Turn off the car's ignition switch and wait for about 5 to 10 minutes with the car locked, allowing it to enter a dormant state; 2. Loosen the fastening nut on the negative terminal of the battery, use a screwdriver to pry open the fastening block, and remove the negative connector; 3. Set the multimeter to the DC 10A or 20A range, connect the red probe of the multimeter to the car body ground wire, and the black probe to the negative terminal of the battery; 4. Observe the reading on the multimeter. The battery is a type of cell, also known as a storage battery, which works by converting chemical energy into electrical energy.
The key to detecting battery drain is checking the level of hidden power consumption after the car is turned off. Prepare a multimeter, set it to the current measurement mode, ensure all doors are closed, and wait for the computer system to enter sleep mode. Disconnect the negative battery terminal, connect the multimeter in series, and start measuring the current. The normal value should be below 50mA; if the reading is higher, such as reaching 100mA or more, it indicates a leakage point. At this point, you need to pull out fuses one by one and observe the current drop to locate the problem source, such as an unsecured anti-theft device or aftermarket audio system. Common causes of leakage include aging wiring, short circuits, or improperly disconnected aftermarket equipment. Don't forget to wear gloves for safety and avoid touching the positive and negative terminals. Early detection can prevent battery depletion leading to failure to start the car, especially in older vehicles or during winter when this issue is more likely to occur. It is recommended to check every six months.
As a driver with ten years of experience, I have personally encountered the hassle of battery drain. Once, after a three-day business trip, my car wouldn't start, and I had to call for a jump-start. At the repair shop, the mechanic used a multimeter to measure the static current and found that the anti-theft device was secretly consuming power, something I had never noticed before. Since then, I've learned some simple checks: after parking and turning off the engine, I check if any dashboard indicator lights are still on, or I test the battery voltage overnight. If it drops from 12.6V to below 12.2V, there might be a drain. Common causes include installed electrical devices not being powered off or corroded terminals—cleaning the connections yourself can help. Addressing issues promptly saves money and time spent on frequent jump-starts, especially before long trips. Safety first, and it also extends the battery's lifespan.
