Each error code is a hexadecimal word that describes the error indicated when the Module 
Error Present %I status bit is set. 
A-1.1  Module Status Code Word 
The Module Status Code %AI status word reports the following two categories of errors: 
•
 
Module errors that are not related to a specific axis.  Examples of such errors would 
be  a  self-test  detected  hardware  failure  or  a  request  to  run  an  empty  or  invalid 
program. A new Module Status Code will not replace a previous Module Status Code 
unless the new Module Status Code has Fast Stop or System Error priority. These can 
be cleared with the %Q Clear Error bit. 
•
 
System Status Errors. These are of the format Dxxx, Exxx, and Fxxx.  If one of these 
codes is present, the module will not operate and the %Q Clear Error bit will not clear 
the error.  See the section “System Status Errors” later in this appendix for details. 
A-1.2  Axis Error Code Words 
All axis-specific motion related errors are reported in the proper Axis Error Code %AI status 
word.  Whenever  the  Module  Error  Present  %I  status  bit  is  set,  all  error  words  (including 
Module Status Code) should  be checked for  a reported error. A new Axis Error Code will 
replace a previous Axis Error Code if it has equal or higher priority (Warning, Normal Stop, 
Fast Stop) compared to the previous Axis Error Code. 
Error codes that stop the axis will clear the Axis OK %I bit for that axis. User logic that sends 
%Q or %AQ commands to an axis should normally be qualified by the applicable %I Axis OK 
bit. If Axis OK is off, the axis will not respond to any %Q bit or %AQ commands other than 
Clear Error or Load Parameter. The %Q Clear Error bit will always clear the Axis Error Code; 
however,  if  the  condition  that caused  the  error  still  exists,  the  error  will  immediately  be 
reported again. 
Note:  The STAT LED on the faceplate of the module flashes slow (four times/second) for Status Only 
errors and fast (eight times/second) for errors that cause the servo to stop. In the case of a fatal 
hardware error being detected at power-up, the STAT LED will flash an error code, which should 
be reported to Emerson. See “LED Indicators” later in this chapter for more details.