Hydraulic Self-propelled scissor lift Common electrical system faults
Aiming at the faults of the scissor platform, this topic is specially listed for analysis, comprehensively reviewing some fault problems encountered in the work in the past few years, analyzing the fault phenomena from the perspective of technical analysis, and digging out the problems from the phenomenon to the essence to provide a solution for the scissors platform. Scissor lift service personnel provide detailed technical analysis.
1. Electrical connection problem
This kind of problem is the most common type. The electrical components on the scissor truck are complicated, and the connection between the various components is also closer. As the car is constantly working, as time goes by, the wiring harness connection on the car will inevitably be damaged. There is damage, especially at the articulations and connector connections. We select one of the common faults for analysis.
1 The vehicle system is powered off
Fault phenomenon: When the vehicle key is turned on to prepare for operation, it is found that the vehicle work indicator light does not work, the digital tubes of ECU and PCU do not light up, and there is no response to the operation of the vehicle.
Troubleshooting: (1) Power switch, Anderson connector, key switch, connector plug connection inspection (2) Power cable connection at the battery (3) Whether the power cable and ground connection on the car are loose
2 02 failure occurs frequently
Fault phenomenon: 02 fault occurs after the vehicle is turned on or during use, and the handle or wiring harness is activated again to communicate normally.
Troubleshooting: (1) Connection of PCU spring wire (2) Inspection of connector (3) Inspection of PCU wiring harness (4) Inspection of main wiring harness terminal connection
3 Control action failure
Fault phenomenon: Occasionally, the input signal of a certain switch cannot be detected or the output signal cannot control the normal operation of the vehicle, and the on-off performance is normal when using a multimeter to measure the on-off. Troubleshooting: (1) Check whether the spring back of the limit switch contact is normal and whether it can be restored to its original position (2) Whether the terminal connection at the ECU connector is normal
Two drive problems
The power drive problem is mainly caused by the faults of the vehicle involving motor movement. It often encounters problems such as the inability to walk, steer, and lift. It may also be accompanied by the appearance of fault codes. When there are fault codes, there is a rough judgment on the fault. The direction of the power drive problem is basically the abnormal output signal of the motor, motor driver and electronic control, which affects the movement of the car.
1 The power of the whole vehicle is insufficient, sometimes good and sometimes bad
Symptoms of failure: Intermittent poor contact, unstable vehicle movement, and sometimes even stop working, unstable motor speed, high surface temperature of the motor, sometimes accompanied by sparks. Troubleshooting: (1) Check whether the speed control signal is normal (2) Observe the inside of the motor during operation, disassemble the motor if necessary, and check the carbon brush and reversing slip ring
2 After the system is powered on, the motor cannot run
Fault phenomenon: The system can be powered on normally, but there is no response when performing walking or lifting actions Normal response signal, which can be verified by power-on test
Three sensor failure
The sensor on the scissor truck is used to measure the body state, tilt alarm, and important safety function. If this function is damaged, please do not use the car to lift the work. The scissors with weighing function are equipped with angle sensor and pressure sensor. These two sensors are important parts of weighing function and an integral part of weighing function vehicle.
1 LL alarm on level ground
Fault phenomenon: The vehicle is on a level ground, and LL alarm occurs after lifting
Troubleshooting: (1) Check and measure the output signal of the inclination switch, whether the output level state can be switched between high and low levels when it is horizontal or inclined (2) Reset the inclination switch, and place the inclination switch on a horizontal plane to perform the reset operation
2 OL alarms occur frequently in vehicles
Fault phenomenon: During the use of the vehicle, there are no heavy objects on the platform, and OL alarms occur frequently.
Troubleshooting: (1) Check whether the installation of the angle sensor and pressure sensor is loose (2) Check the change range of the angle sensor, whether the voltage changes from large to small or small to large according to a certain ratio (3) Check the pressure sensor , During the lifting process, whether the voltage change is a U-shaped change curve (4) Re-calibrate the weighing function, re-calibrate with no load and full load.
Four electronic control system failure
The faults of the control system come from the hardware and software of the system. For products used in the market, when the control system fails, the proportion of software problems is smaller. When the product is debugged at the factory, it will go through a full factory debugging process. Generally, there are not many software faults, unless It is some problems caused by reflashing the software during the use of the vehicle, and insufficient verification of the software. The stability of hardware is a major culprit of controller failure. EMC problems, insufficient circuit protection design, and unreliable materials may cause some hardware problems.
1 The operation is not normal after updating the software
Fault phenomenon: It was used normally before, but the software was updated without replacing the parts, and the vehicle moved abnormally
Troubleshooting: (1) Check the controller parameters to see if there is any modification compared with the original (2) Flash back to the previous version of the software, and compare and verify whether the function is intact
2 Controller 02 failure
Fault phenomenon: 02 alarm occurs after the handle is connected and turned on, check that the wiring harness connection is normal
Troubleshooting: (1) Replace the handle, reconnect and check (2) Replace the lower control ECU, and re-power on for inspection
3 The vehicle cannot move, and the signal has no output
Fault phenomenon: After the system is powered on, the vehicle does not respond to a certain action
Troubleshooting: (1) Check whether the wiring harness connection is normal (2) Measure the output signal of the corresponding action with a multimeter, and observe the measured value
4 Power-on controller displays 8.8
Fault phenomenon: After the vehicle is powered on, the ECU or PCU displays 8.8, and there is no action response
Troubleshooting: (1) Measure whether there is a short circuit in the power supply (2) Replace the device that displays 8.8 after confirming that there is no short circuit.
For more information about the hydraulic self propelled scissor lift. Welcome to contact us.
Shandong Cathay Machinery Co., Ltd
www.cathaylift.com
Email:sales@cathaylift.com
