Fault Phenomenon: XCMG truck crane operating the control handle, the corresponding action does not respond or is uncontrollable, handle feels sticky.

Troubleshooting Process:
– Checked control lever mechanical connection: connection ball joint detached.
– Checked multi-way valve spool: spool stuck due to oil contamination.
– Replaced ball joint, disassembled and cleaned multi-way valve.

Root Cause: Hydraulic oil contamination caused the multi-way valve spool to stick.

Required Parts: Multi-way valve repair kit, hydraulic oil.