Fault Phenomenon: SANY SW956 wheel loader high hydraulic oil temperature, inspection reveals cooling fan not spinning or spinning slowly.

Troubleshooting Process:
– Checked motor: fan drive motor internal leakage or seized.
– Checked control valve: fan motor control valve spool stuck.
– Checked temperature sensor: water/oil temperature sensor signal error.
– Checked belt: mechanical drive belt broken.

Root Cause: The hydraulic drive fan motor is internally worn with internal leakage, unable to obtain sufficient torque to drive the fan at high speed.

Required Parts: Replace cooling fan hydraulic motor.