Troubleshooting: Ejector Not Working on a Vertical Machine

If the ejector does not move, work through these checks in order:

• Confirm the hydraulics. Start the motor and pump and, in manual mode, move the injection unit forward and back or run injection and recovery. If these work, the pump, proportional pressure valve, proportional flow valve and their circuits are fine.
• Check settings and signals. Verify ejector pressure, speed, position and count. Press the ejector button and check whether the directional valve solenoid receives a signal — usually 24 V DC (a few older machines use 220 V AC). If there is no signal, look for a disconnected signal wire, check whether the I/O board output port has voltage, and then check the output power transistor or intermediate relay.
• Check the solenoid coil. Measure coil resistance; a coil can break internally or burn out and must then be replaced.
• Check the valve spool. Debris — often from aged seals or worn metal parts in the oil circuit — can jam the spool. Disassemble and clean the valve.
• Check the ejector cylinder. Damaged seals causing internal leakage, or a broken piston rod, will also stop the ejector.
• Check the limit switch next to the ejector cylinder.