I have been working on an older (90's) style 460 volt 3 phase VFD. Upon slowing down, the precharge contactor slams in and out several times and then gives a drive fault light and has to be reset to run. I also receive an overtemp and drive lock LED. All voltages are stable including the 120 volts across the precharge contactor coil. I have swapped the main control board, power interface board, the options board and all six gate boards with no effect. Has anyone out there experienced this, and what was the fix?