What you will see
A 901.00 Service Engine displays upon entering the Diagnostic Menu to test or implement countermeasures that may address an initial service error; for example, 133.xx or 121.xx errors.
Solution
Firmware LHS42.TQ(P).P538, or greater, is known to address this issue. Contact Lexmark Technical Support andreference this article ID# SO7939 when you request this firmware.
NOTE: Firmware updates require the printer be in a Ready state; therefore, any existing printer error will prevent a successful firmware update. Hence, you will have to force the printer into an Entering 'Invalid Engine Code' state to allow firmware updates state to allow the printer to accept the firmware flash file.
If the issue persists, search for more information related to this issue or contact support for further assistance.
LEGACY ID: SO7939