Fault Phenomenon: Shantui DH46 fan runs normally when cold. After reaching operating temperature (water temp 95℃), the fan stops spinning, water temperature continues to rise, and the dashboard shows a high-temperature alarm.

Troubleshooting Process:
– Checked fan belt tension: normal, no slipping.
– Checked water temperature sensor resistance: changes normally with temperature, linear.
– Checked fan clutch supply voltage: voltage reaches connector normally.
– Measured temperature switch signal at operating temperature: found the temperature switch signal cannot be transmitted to the actuator.

Root Cause: Internal temperature-sensing element of the silicone oil fan clutch fails, preventing it from locking.

Required Parts: Silicone oil fan clutch assembly.