How to check the page count on it?

Any ink level feedback is non-existent, just a best guess.

If the new firmware is applied, I believe that the engine code has been updated too.

After the code update, you will need to force a calibration.

a. Press Menuon the printer's Op panel.
b. Look for Settings.
c. Select Quality Menu.
d. Select Color Adjust.

Note - Some cartridges may trigger toner low soon after a few (maybe 20 or more) pages have been printed, this should be expected.

If the long calibration persists, look at the Page Count for each cartridge by printing the Device Statistics page.

Note: If you are unable to print, you may check the page count using the printer's Embeded Web Server (EWS).
a. Launch the Internet Explorer browser.
b. Type the IP address of the printer.
c. Click on "Reports."
d. Select "Device Statistics."

If any of the Page Count is close to the expected yield (example: 8500 page count for a 10K yield cartridge), but the device statistics, says 'OK' in Supply Levelor it reports FULL on the Status/Suppliesfrom the printer's Op panelor Supplies Menu. Replace the cartridge with a new one of the same yield.

For further assistance, please contact Lexmark Technical Support.

The instructions for getting the page count for the C210SF should be the same as for the C231SF:

- Press User Tools.
- Scroll down until you see Reports Print.
- Press OK.
- Scroll down to either Configuration Page (2 pages long, prints in black and white) or Maintenance Page (1 page long, prints in color).
- Press OK.

Both the configuration page and the maintenance page will show the page counts. For page count instructions on other models of copiers or printers, check out ConfigPages.Blogspot.com.

You can't physically change the printer's page count; it's stored in the non-volatile memory or read-only memory. Did you mean check the page count? You can check the page count by printing out a configuration page:

- Press Setup.
- Scroll to Reports.
- Press OK.
- Scroll to Config Report.
- Press OK.

You can print a printer status report,print self test page from printer as standalone.there are details mentioned there about the page printed by your printer since you set it up.Page count started from the first time printer prints anything when you set it up and it collates all of it till present.

You also need to consider the ype of printer you have.

You can also print test page from PC to printer

this is example for windows xp.
windows xp is printers and faxes
windows vista is hardware and sound then printers
windows 7 is devices and printers

Learn how to print a self-report page from the product with Windows. Printing a self-test report from Windows
NOTE: The exact steps to open the Printers or Printers and Faxes window might vary depending on the version of Microsoft Windows being used.

1. Click the Start or the Windows Vista button ( ).
2. Click Printers or Printers and Faxes .
3. Click the desired printer icon to highlight it.
4. Click File , and then click Properties .
5. Click the Services tab.
6. Click Print a Test Page .

Usage page
Shows a page count for each size of
paper printed, the number of one-sided
(simplexed) or two-sided (duplexed)
pages, and the average percentage of
coverage.
1. From the Home screen, touch Administration.
2. Touch Information.
3. Touch Configuration/Status Pages.
4. Touch Usage Page.
5. Touch Print

Configuration page
The configuration page lists current settings and contains a status log report.

To print the configuration page from the printer, press GO for 5 seconds, until the yellow light comes on, when the printer is in the ready state.
NOTE Make sure that you hold the GO button for less than 10 seconds.

Press menu and scroll thru selections, look for reports and select config page. When it prints it gives all the toner levels and print counts.

You have to print out the meter report.

1. Press the [Reports] button on the Control Panel
   
   
   
   
2. Press the [Up] or [Down] arrow until 'Systems Data' is displayed on the Display Screen.
3. Press the [Enter] button.
   
   The System Data list will be printed with the following information:
   • Total Page Counts: Total number of pages printed
   • CRU Prints: Number of pages printed using the current Toner (Dry Ink) Cartridge
   • Replaced Toner Counts: Number of new Toner Cartridges installed in the machine
   • Replaced Drum Counts: Number of new Drum Cartridges installed in the machine
   • Current Drum Page Counts: Number of pages printed using the current Drum Cartridge
   • Platen Scan Page Counts: Number of pages scanned using the Document Glass
   • ADF Scan Page Counts: Number of pages scann

If the printer was reset recently then you will not et the entire or exact page count till day, but you can still run a Print self test report and check for the information:
To Run:

1. On the front panel of the product, press Menu (or Setup) .
2. Press the Right Arrow until Print Reports displays, and then press Enter, Start, or OK .
3. Press the Right Arrow until Self-Test Report displays, and then press Enter, Start, or OK .

It will print a self test page and you will find the page count in thie page

Good Luck