What is the reason for the wrench warning light appearing in the car?

[McJaxson]

The wrench light is a maintenance reminder light. It illuminates when the vehicle has reached a certain mileage, indicating that maintenance is required. The maintenance cycle of the car is preset at the time of manufacture, and the wrench light will appear at regular intervals to remind the driver to perform timely maintenance. For some car models, the wrench symbol will disappear after maintenance is completed; however, for others, it may not automatically disappear and must be cleared via a computer. The hazards of long-term lack of car maintenance are as follows: Brake fluid deterioration: Since brake fluid contains ethylene glycol, it deteriorates when exposed to water. The brake system is external and easily absorbs moisture from the air. If not replaced for a long time, moisture will mix in, leading to brake failure or inability to stop the car. Engine failure: If the car is not maintained for a long time, the engine may fail. Due to deteriorated or insufficient engine oil, internal components will wear severely. Thickened oil prevents proper lubrication of the engine, leading to issues like cylinder burning, cylinder scoring, or cylinder seizure. Brake pad wear: Frequent braking while driving, combined with long-term lack of maintenance, can cause severe wear on the car's brake pads, resulting in brake failure.