Final answer:
Before testing the charging system in a car, it is common practice to check the condition of the car battery.
Step-by-step explanation:
Before testing the charging system in a car, it is common practice to check the condition of the car battery. The car battery is a crucial component in the charging system as it provides the electrical energy needed to start the engine and power other electrical systems in the car. To test the condition of the battery, you can use a battery tester or a multimeter to measure its voltage and check for any signs of damage or wear.