Hi,
the problem you are experiencing is most likely due to a bad connection on the FP modules' terminal bases. First of all you should check for any bent pin on the Terminal basof the FP-2000 and/or the FP-AI-110. If the system has more than 1 module in the FP bank, try and swap the terminal bases until you find the faulty one.
HINT: you know which Terminal Base is faulty because every module downstream from it should show a Ready LED in the off state.
AlessioD
National Instruments