@chefrp
Why would this plane be flying around so long with this known fault?
In addition what Volume mentioned, compounding the issue was AirAsia's use of two different, non-integrated fault reporting systems (the MR1 technical log and the PFR post flight report).
Specifically, intermittent faults from the PFR which were "resolved" by simple resets were not being logged into the MR1. The PFR was mainly used as an aid to troubleshooting.
However, AirAsia's maintenance management system (AMOS) was only based on the MR1. So procedures in place to identify and fix recurring issues did not flag this problem.
Also, AirAsia pilots did not report many of the FAC failures. Maintenance work arising from pilot reports would have been logged in the MR1, and could have resulted in the issue to be flagged as recurring.
But some AirAsia pilots apparently had simply reset the problematic FACs in flight and not subsequently report the issue to maintenance.
Lots of holes in the Swiss cheese.