SF fault em231 & em232

hi all..
i am facing SF(red led blinking) in my TWO analog cards,,cards are
1-EM231
AI8*TC PID
2-EM 231
AI8*16 BIT

how i can rectify these fault,,whether fault are from field or its hardware fault of analog module?? or any other method??

https://support.industry.siemens.com/tf/ww/en/posts/em231-rtd-problems/25098/?page=0&pageSize=10

The above thread may help you out.
Regards,