What functions need to be verified during the low-speed test drive of a new car at the port

The new car has undergone long-distance sea transportation, and the bumpy and salt spray environment may cause component displacement and seal deformation. Many potential faults are difficult to detect in a stationary state. High speed testing also poses safety risks. Low speed testing is the safest means of arrival inspection, with a focus on slowly driving within 5km/h for item by item verification. At the starting stage, check the clutch and transmission system first. For manual models, slowly release the clutch and observe whether there is any slippage, impact, or abnormal noise during the start. For automatic models, check whether the forward and reverse gears are smoothly engaged without any jerking or delay. Switch back and forth several times to confirm that the power take-off and gear shifting mechanisms respond normally. The steering system is a necessary inspection item. Turn the steering back and forth at low speed and small angle, feel whether the steering is stuck or heavy, pay attention to whether there is any abnormal friction or noise, whether the left and right steering limits are normal, and check whether there is any leakage in the steering pipeline joints. Next, test the braking function by lightly tapping the brakes at low speed to check for timely braking response, deviation, and abnormal noise. For trailer models, test the trailer brakes separately to confirm the synchronization of the trailer brakes. For air brake models, pay attention to whether the brake exhaust sound is normal, whether the brakes can fully return to their original position after releasing the brakes, and whether there is any drag brake heating. Then check the lighting and various electrical functions, turn on the high and low beams, turn signals, brake lights, clearance lights, and reverse lights in sequence, while testing the horn and wipers, and observing the dashboard indicator lights, ABS, Are there any abnormal alarms for air pressure, engine oil, and malfunction lights during idle and low-speed driving. Also pay attention to chassis noise, low-speed straight driving and small turns, carefully listen to the suspension, steel plate bushings, and transmission shaft areas for intermittent creaking and impact noise, and determine whether there are loose fasteners or damaged rubber parts. The hydraulic system is designed for dump truck models, and the lifting action is tested in a small amplitude at low speed in place to observe whether there is any jamming or abnormal noise during lifting, and whether the hydraulic pipeline joints are leaking oil. Do not lift at full load throughout the entire process, only perform functional verification. During the test drive process, observe the changes in instrument air pressure and oil temperature synchronously, confirm that the rate of air pressure rise is normal, the pressure remains stable, and there is no continuous pressure drop. After the test drive is completed, check the chassis pipelines and joints again to identify any leakage issues that only appear after low-speed operation. Many acceptance personnel are accustomed to conducting static inspections directly, ignoring low-speed dynamic testing. Some looseness problems caused by sea transportation are only exposed after the vehicle undergoes slight load-bearing movements. The new car undergoes low-speed testing upon arrival at the port to verify the basic functions of transmission, steering, braking, electrical, and hydraulic systems under low load. Hidden faults caused by sea transportation are checked in advance to avoid sudden problems after delivery to customers and reduce overseas after-sales disputes.