The replacement of car batteries is relatively simple, requiring a wrench and a multimeter. The main steps are as follows:

1. First turn off the car, open the engine hood, and find the location of the car battery.

2. Use a digital multimeter to check the car battery voltage. If the battery voltage is lower than 12V, charge the battery and perform a battery load test to determine whether the car battery is good or bad.

3. After confirmation, first remove the battery negative cable, and then remove the battery positive cable.

4. Next, remove the car battery fixing clip. At this time, you can take out the battery. Be careful not to tilt the battery angle during the removal process, and there will be problems such as liquid leakage on the side.

5. After cleaning thecar battery tray, put the new battery into it and reinstall the car battery fixing clip.

6. Next, connect the positive cable first, and then connect the negative cable.

7. After the new car battery is installed, start the engine and check the charging system with a digital multimeter. The car battery voltage should be between 13.5-14.5V.