異常 is certainly abnormal but try to avoid using it as much as possible. You must know that Japanese writers use 異常 much more often than English writers use abnormal in this context. Many of those 異常 would be something other than abnormal if the same writer were writing in English.
I cannot tell what it is for sure just from this sentence, but try to read what it is from the wider context. It could be anything that they don't expect in a normal operation, i.e. faulty output, unexpected output, or just error.
構成要素 is components. but の異常出力 is likely "from" those component, not in.