I have a lexmark T520,
Hello thanks for using Fixya
929 Service Toner Sensor error indicates a problem with the toner
sensor, the front harness cable, or the developer drive. It could also
mean that the toner cartridge is defective.
The most likely cause of
this error is the toner cartridge itself. This is especially true if it
is a new cartridge and the error started after you installed it.
To solve it try this:
the cartridge out of the printer and locate the encoder wheel on the
right-hand side of the cartridge. The encoder wheel can be found on the
right side of the cartridge (usually over a bar code sticker). It is a
thin, black, plastic wheel with small rectangular notches cut into it.
This wheel will sometimes get stuck, but you can free it by turning it
Try moving the wheel forwards and backwards a little. If
it does not turn correctly, you will receive a 929 Toner Sensor error on
the printer when you try to use the cartridge it is attached to
The encoder wheel moves only a little bit each way. It should not make a
complete revolution. If it does, the wheel is probably broken.
to move it a little bit each way a couple of times to see if you can
free it up. Caution! DO NOT force the wheel as you could break it.
the wheel on the toner cartridge is stuck, try another new toner
cartridge. ( If you do not have another new toner cartridge available,
an old toner cartridge or another cartridge from a working printer of
the same model will also suffice for this test.)
Power the printer off
and install the second toner cartridge. Then power the printer back on.
If another toner cartridge clears up the 929 error, the printer is fine
and the problem is with the toner cartridge.
If the error does not
clear, there may be a problem with the printer.
If you narrow down
the problem to the toner cartridge, call the point of purchase and
explain the situation to them. They may have a replacement policy.
you receive this error with a second toner cartridge, you may want to
check if the Front Harness Cable is plugged into the Toner Sensor then Do
Turn off the printer and remove the toner cartridge.
inside the printer at the place where the cartridge goes (on the
right). You should see the Toner Sensor. On the back of the sensor
assembly, you should be able to see a white cable connector.
Push this white cable connector into the toner sensor assembly by pushing the connector towards the front of the printer.
If you continue to receive the 929 error the final option is your printer will probably need service.
I hope this solution will helpful 4 u
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on Feb 11, 2011