System fault diagnosis of all actuators of the excavator and related fault code display!
A-1 Excavator all actuators are slow and no related fault codes are displayed.
1) Due to some reasons or due to the failure of the pilot system, the flow of pump 1 and pump 2 is reduced, which can cause this kind of failure.
2) Even if the speed is satisfactory, but the power is weak, the fault diagnosis of the overflow valve (F-1) should be carried out at this time.
During the inspection, check whether the wiring harness connector is loose or not.
A-2: During a single walking operation, left walking is not possible; the speed of a single rotation operation is low; the speed of the stick is slow when the stick is pushed horizontally (all faults occur at the same time) This fault has related fault code 09 , 11, 13, 14, 21 display.
1) For some reason, the flow rate of pump 2 is reduced, so that the left travel motor and the swing motor driven by the hydraulic oil of pump 2 move very slowly.
2) The hydraulic oil from the pump 1 also flows to the stick and boom hydraulic cylinders so that the stick and boom can move at a slower speed during a single operation. However, in the horizontal pushing operation, the hydraulic oil flows to the boom before it flows to the stick, so the speed of the stick becomes very low.
3) If the turning speed is normal, monitor the pilot pressure of turning and check whether the pressure of the turning joystick is 0MPa when in neutral.
When checking, check whether the wiring harness connector is loose or not.
A-3: In a single walking operation, right walking cannot be performed; the bucket is operated at a slow speed alone; the boom cannot be raised normally during the horizontal push of the stick (all faults occur at the same time) there are related fault codes 08, 10, 12 , 20 display.
1) For some reason, the flow rate of pump 1 is reduced, so that the right travel motor driven by the hydraulic oil of pump 1 and the bucket hydraulic cylinder move very slowly.
2) The hydraulic oil from the pump 2 also flows to the stick and boom hydraulic cylinders, so that the stick and boom move at a slower speed during single-one operation. In the horizontal pushing operation, the hydraulic oil flows to the stick before it flows to the boom, so the boom can hardly be lifted.
During the inspection, check whether the wiring harness connector is loose or not.
A-4: Return the joystick to neutral, and the actuator action will not stop. This fault has no related fault code display.
When this failure occurs, first suspect that the pilot valve spool is stuck or the main spool in the control valve is stuck.
