The common steering assist system is divided into electric steering assist system and hydraulic steering assist system. Because the electric power steering system is more precise and is not easy to have problems, it is suggested that the maintenance station be repaired for the fault of the electric steering system. First, let's get a general understanding of the principle of hydraulic steering assistance system. The power source of the hydraulic steering system is from the steering aid pump driven by the engine belt. It turns to the power pump to produce the oil pressure and the mechanical device in the steering wheel, so that the steering wheel is easy to operate. When the steering wheel is full, the steering mechanism will reach the limit position. At this time, if the steering wheel continues to turn, the oil pressure in the steering system will continue to rise, but the oil pipe of the steering system will not break, and the safety valve is set in the hydraulic pipeline, and the high oil pressure will be discharged through the safety valve, and the abnormal noise is at this time. It is due to pressure relief. However, if this operation is done for a long time, it will cause premature damage to the steering pump or steering tube. In addition, if the tape of the driving steering pump is aging or slack, the abnormal sound will occur when the steering wheel is filled. Therefore, the vehicle should be maintained regularly to check the working conditions of the easy to wear parts.