Fault Phenomenon: Palazzani RJI52 telescopic boom aerial work platform after engine stall, operating the emergency pump, the boom cannot be retracted.

Troubleshooting Process:
– Checked emergency pump battery: battery dead.
– Checked emergency pump motor: motor burnt.
– Checked manual valve: manual valve not opened.
– Checked hydraulic oil: level too low.

Root Cause: The Emergency Power Unit (EPU) battery is depleted or the motor is faulty.

Required Parts: Emergency pump battery or motor assembly.