How to Check Car Battery Power Level?
2 Answers
Check car battery power level with the following methods: 1. Battery appearance inspection: If obvious deformation or bulging is found on both sides of the battery, it needs to be checked and replaced. Additionally, observe the battery terminals. If white or green powdery substances appear around the terminals, it indicates battery issues, as these powders are oxides from inside the battery. Normally, newer or higher-quality batteries won't show this condition. 2. Inspection window check: Over 80% of batteries have an inspection window, usually located on the top. The visible colors in the window are divided into three types: green, yellow, and black. Green indicates sufficient power, yellow means slightly discharged, and black means it's almost dead and needs replacement.
Every time I check the battery level, I start with the headlight observation method: at night in the garage, I turn on the headlights for a few minutes with the engine off, then start the vehicle. If the lights noticeably dim during startup, it indicates insufficient battery charge. Additionally, cold starts are a good opportunity to check—if the starter sounds sluggish and weak, it's almost certainly a battery issue. I always keep a simple voltmeter in my car toolkit and measure the voltage once a month—if it reads below 12.4 volts when the engine is cold, it's time to be cautious. Last time my battery died was because I forgot to turn off the dashcam after parking, which drained the battery over three days. Now, I make it a habit to double-check all electronics after locking the car.
