If a red warning light with a plus and minus sign in the center of a rectangle illuminates on your car, this indicates a malfunction in the vehicle’s charging system. There are many possible causes for this issue; the specific causes and solutions are as follows:

1. The alternator belt may be worn, carbonized, or too loose, causing the belt to slip and produce abnormal noises. This results in the alternator losing speed, triggering the warning light. This can be resolved by replacing the alternator drive belt. When replacing the belt, be sure to select one that is compatible with your engine.

2. Damaged alternator bearings can also cause the alternator to spin freely. The alternator’s rotor and stator may come into contact and rub against each other, leading to overheating. In this case, the bearings must be replaced.

3. Loose or corroded battery terminals. If the terminals are loose or have a poor connection, simply reconnect them securely. If the cables are corroded, they must be replaced.

4. Ground loop fault: Turn on the ignition switch. Without starting the engine and while the charging indicator light is on, disconnect the alternator’s wiring harness connector. The charging indicator light should now turn off. If it remains on, it is likely a ground loop fault, and the relevant wiring should be properly reinstalled.

Additionally, a faulty charging system is often accompanied by various symptoms. When starting the vehicle, you may notice significant difficulty in turning the engine over, making it hard to get the starter motor running normally. It is also possible that when you turn the ignition switch on, none of the lights on the instrument panel illuminate. If this occurs, you can troubleshoot the issue step by step using the methods described above. If you are unable to identify the specific cause of the problem, you should promptly visit an authorized dealership or repair shop for inspection and repair.