There should be a card included with the postscript kit. The dealer should have submitted the registration code with the machine's serial number in order to obtain a product key which they are then supposed to write down on the card, make a copy for themselves, and send you the card in the PK1 box.
Here is the manual link
Press CTRL+F Type in 'tax' top right, press Enter. Scroll through the 19 mentions, Number 3 shows it. Copied and pasted below, but it doesn't show symbol image. The first paragraph covers getting into setting mode and setting date and time, then comes 'Tax Rate'.
https://www.manuallib.com/download//SHARP-EL-1801PIII-OPERATION-MANUAL.PDF
GT • RATE SET GRAND TOTAL / RATE SETTING MODE SELECTOR: "GT": Grand Total "•": Neutral "RATE SET": To set the date, time, and tax rate, set this switch at the "RATE SET" position. Date: • Enter in the order of month, day and year, then press to complete the entry. • Use to separate month, day, and year. • When is pressed, the number entered is evaluated and displayed as "date" if the value is within the following range; "Error" is displayed otherwise, and the previously set date is restored. Month: 1 - 12; day: 1 - 31; Year: 2000 - 2099 (in 4 digits) or 00 - 99 (in 2 digits) Time: • Enter in the order of hour, minutes, then press to complete the entry. (There is no entry available for the seconds value. The clock starts at zero second.) • If the hour/minute digit is less than 10, it is not necessary to enter the first digit "0". • Use to separate hour and minute values. • When is pressed, the number entered is evaluated and displayed as "time" if the value is within the following range; "Error" is displayed otherwise, and the previously set time is restored. Hour: 0 - 23 (24-hour system for the hour entry), Minute: 0 - 59
Tax rate: • Press three times, enter the tax rate, followed by . • A maximum of 4 digits can be stored (decimal point is not counted as a digit). • Only one rate can be stored. If you enter a new rate, the previous rate will be cleared.
more here and videos
https://www.google.com/search?q=sharp+el-1801piii+set+tax+rate
..
Sharp Global
https://global.sharp > pdf > ERR_Message_EN
PDF
002-500. An error occurred during the scan job. Execute the operation again. Also, check whether or not the account limit for the. Scan service is set. 003-311.
114 pages
PrintCopy .info
https://printcopy.info > brand=Sharp > model=MX7090
Causes: Scanner expansion PWB (ACU) (ACRE) ROM data error. An error occurs during firmware upgrading for some reasons. Remedy: Perform firmware upgrading again.
Question edited for clarity, add magic word.
Question moved from Misc category.
This says;
How do I reset my printer toner chip?
Press the tiny reset button located beside the chip and hold for 10 seconds. Depending on the brand and model of the cartridge, you may not need to hold the button for 10 seconds, but it won't harm the cartridge so do it anyway just to be safe.
What OS does your computer have? I have found a site that claims to have the PCL6 drivers for Vista and Windows 7 (32-bit) and earlier versions of Windows. https://www.driveridentifier.com/scan/sharp-ar-m420u/download/1550221446/A13F4E2F524A4FE29DF6E43348CDEF86/LPTENUM%5CSHARPAR-M420U8CB4 . However, several of the drivers are listed as 3rd party and in the .rar format. (You need 7-Zip or a similar program to extract that archive.) If you have a recent version of Windows, the above driver packages won't help. Windows 10 and 11 require manufacturer signed 64-bit drivers.
I don't see an AR-M420 listed at https://global.sharp/restricted/print/select.html?view=2& . I tried several regions. It looks like the manufacturer stopped supporting the unit.
Unfortunately, this all-in-one printer will not interface with any wireless phone or gadget. (If it has a Fax function, it might let you daisy chain it to a landline wired phone.) I wish that I had better news for you.
Cindy Wells
A common cause of faded or faint printouts from your inkjet printer, is dried ink particles causing a blockage. The printheads on an ink cartridge can be become blocked if the printer is not used for a period of time, so it is recommended to print a few pages each month to maintain the print quality
A quick way is to disconnect from the mains wall plug for one minute, then press and hold the Power button for 30 seconds. Plug back in.
Or the Manuals
e7-23Laser beam Sensor trouble (Yellow)
REBOOT - if fault returns on first use consider disabling function or informing user not to use function that is causing problem until sharp technician arrives
https://www.copierrental.com/post/sharp-error-codes-list
