Issue
After an attempt to cold start the controller by removing AC power with the batteries disconnected, the unit started up with its CPU light flashing very rapidly (hard failure mode)
Environment
ACX780
ACX781
Cause
Partly cleared memory.
The random access memory (RAM) on the ACX78x take a long time to erase.
Resolution
Remove the batteries
Power down the unit
Wait 5 minutes
Power up the unit