Just a long shot.
Anybody else else suspected the EEPROM in a DE-5000 LCR ?
Mine started displaying really suspect readings after sitting for a year or two and will no longer calibrate getting stuck at "Srt -00-".
So I think it might be stuck waitingg for the (passed) calibration to write to EEPROM.
I have not yet properly probed or replaced the device.
Jon