An Dongfeng EQ1118GA car. User response: when the car opens the ignition switch and starts the engine, the starter sends out the dangling sound. Fault detection: after checking and identifying the fault in the starter, the starter will be removed and tested, and there is still a slight "Dangdang" sound in the starter. It is found that the armature axis of the starter is too large and the gap between the armature axis and the supporting copper sleeve is too large, so that the unidirectional clutch on the axis of the armature swings too much. Troubleshooting: after replacing the front and rear support copper sleeve of the starter armature into new product, the failure phenomenon will disappear. Failure analysis: because of the long use of the starter without maintenance, the lubrication between the front end of the armature shaft and the copper sleeve is not timely, the time is too long to wear, so that the copper sleeve is damaged, the armature shaft and the supporting copper sleeve are too large, and the swing of the unidirectional clutch on the armature axis is correspondingly larger when starting, and it can not be accurately meshed with the flywheel gear ring. It causes collisions, resulting in the phenomenon of dangling sound.