What's wrong with the small wrench in the car?

A small wrench appeared in the car to remind the vehicle to be maintained. The small wrench fault light is a maintenance indicator light, and this light is not a vehicle fault. The function of the maintenance indicator lamp is to remind the driver to maintain the vehicle after it has traveled for a certain mileage. When the small wrench lights up, you should go to the 4S shop for repair. After the maintenance, the maintenance light will go out after returning to zero. The function of automobile maintenance: to ensure the excellent performance of vehicles; Improve driving safety; Reduce engine noise; Extend the service life of the vehicle. Vehicle maintenance items include: replacing oil and oil filter; Replace oil filter, air filter, gasoline filter, air conditioner filter and gearbox oil filter; Adding glass water, antifreeze and air conditioning refrigerant; Check whether the drive belt is worn; Clean the carbon deposit on the throttle and cylinder; Check whether the chassis is damaged; Check the body and tires.