Went to use my lift, soon as I disengaged the emergency stop button on the control box, the pump kept running it wouldn't shut off. Had to engage the emergency battery disconnect switch. The DC power solenoid was no good. Changed it out with another solenoid from a spare lift. It would drive, but when I tried to raise the platform, the solenoid failed and the pump kept running. Had to engage the emergency battery disconnect switch again to shut it off. What is causing the Solenoid to fail? Thank you in advance.