Sparc T4-1 + Sensor | minor: Temperature : /SYS/MB/DVRM_M1/T_EXT : Lower Non-critical going low : r

Hello team,

I'm facing on problem on Sparc T4-1.The server twice hang

Often the System have an outage and shut down  and on the sp you may see various problems in the logs as :

Sensor | minor: Temperature : /SYS/MB/DVRM_M1/T_EXT : Lower Non-critical going low  : reading -10 <= threshold -5 degrees C

Fault | minor: Warning: System Temperatures approaching operating limits

SDM | minor: (Part Number:N/A, Serial Number:N/A, Reference Document:http://support.oracle.com/msg/)

I need your help please

Best regards

Lou