ET200X fault

I have an ET200X rack talking to an S5 main chassis. The 200X has 4 2-channel RTD cards pt100 type. Two of the RTD's have failed and cannot be replaced at this time. When I looked at the rack, it had power, Steady System fault and blinking Bus Fault. When I disconnected the two failed RTD's, the faults and the power go away. Reconnecting either failed RTD causes power and the faults to come back. Any ideas? Thanks for looking and the help.

Al Anderson