We should expect Rx light no lower than –13.50 [Expected range between –9.0 to –13.50]
show controllers [interface] phy | i “Rx|Tx” – to display light levels on IOS XR
show interface [port number] trans det | i Power
show int [port#] tra det | i Tx|Rx
show hw-module subslot 0/2 transceiver 1 status
To check SFP Tx
show int [interface] transceiver
show int [interface] transceiver detail