Question edited for clarity.
Error codes should be on the rear label according to the Technical Manual
https://www.partstown.ca/modelManual/HOB-AM15T_spm.pdf
There is no E1 error code for that machine and is is suggested that the display may be faulty.
https://www.google.com/search?q=hobart+am15+e1+error+code
The only reference to E1 is here, for the AM-16 and an electrical 'type'.
https://www.hobart.ca/wp-content/uploads/pdfs/warewash/AM16-BAS-Base-Electric-CF48568.pdf
For LXi machines
Drain and fill error messages are displayed as E0, E1, E2, E3, E4, E5, E6 or E7. In all cases, the dishwasher will terminate current cycle operations, turn off all heat sources and display the message until the OFF button is pressed. (A power drain will not occur when turned off.) (See Troubleshooting.) If problem persists, contact your local Hobart Service Office
Phone Hobart Support. there are no Hobart Techs here, just me as caterer, career long Hobart user and Expert finder of information. Or try JustAnswer dot com.
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