8 Troubleshooting
8.9 Error codes
Instrument display
Error
code
51
I/O-box
Error
code
20
21
22
23-28
420
Description
High temperature
Description
High temperature
Analog in signal below -2V
Analog in signal above 2V
Internal instrument error
Action
See Instrument display, on page 411
Action
See I/O-box, on page 410
Check the external equipment connected
to the I/O-box.
Check the external equipment connected
to the I/O-box.
Restart the instrument. If recurrent please
contact Service.
ÄKTA avant User Manual 29035184 AE