Affected Products:
Single-Function: B2338, B2442, B2546, B2650, M1242, M1246, M3250, MS32x, MS42x, MS52x, MS62x
Multifunction: MB2338, MB2442, MB2546, MB2650, MX32x, MX42x, MX52x, MX62x, XM1242, XM1246, XM3250
Issue Description:
A 938.04A Service Engine Electronics Error appears on the printer display.
Solution:

Power off the printer, wait for a few minutes and power it back on.

Remove the toner cartridge and replace it with a known good cartridge. Observe if the error remains.

Remove all the supplies (toner cartridge and imaging unit) from the printer.

Power off the printer, wait for a few minutes and power it back on.

Observe whether the printer posts a 31.xx and not 938.04A error after removing the supplies.
Should the printer posts 31.xx, reinstall back the supplies one at a time (imaging unit first then toner cartridge) until the 938.04A error re-appears.
Replace the defective supply once it is narrowed down.
Still Need Help?
Have the following available when calling Lexmark Technical Support;
Printer model(s)
Printer serial number
Toner/imaging unit/waste toner bottle part number and serial number
Capture the Logs Gzip Compression file. Refer to
xref_FA958_xref for the steps.
LEGACY ID: SO8891