Lexmark C750 Service Manual page 127

940 Error code
Cyan toner metering cycle (TMC)
Toner metering cycle (TMC) is where the code and electronics in the printer sense an addition of toner in the
cartridge developing area. If the printer is expecting a toner addition cycle but one is not detected, a 94x TMC
Error is displayed.
Replacement of the cartridge may fix the problem temporarily if the problem is with the printer. Only replace the
cartridge if there are no problems with the printer or if the cartridge is known to be defective.
Note: Before proceeding with this service check, observe the error log for repetitive occurrences of a 94x
service error.
Step Actions and questions
1 Check the toner metering cam (A) on the rear of the
cyan cartridge.
Note: In some cartridges the toner metering cam is
black.
Is the cam present on the cartridge?
2 Check the TMC pin (B) in the cyan cartridge contact
assembly to make sure it moves freely.
Does the pin move freely?
A
B
Yes No
Go to step 2 If the toner
metering cam is
not present, check
the printer to make
sure it is not inside.
Replace the
damaged
cartridge.
Go to step 3 Replace the
cartridge contact
assembly.
Diagnostic information
5060-00x
2-93