Lexmark C920 - HVU Error; 926(K), 927(C), 928(Y), 929(M) - Toner Sensor Error

2-12 Service Manual
5056-XXX
925 - HVU Error
926(K), 927(C), 928(Y), 929(M) - Toner Sensor Error
Step Questions/actions Yes No
1 Has the high voltage power board (HVU) been
removed/replaced?
Inspect the
secondary card
on the high
voltage board
(HVU) for a
broken
component
(Q906). Replace
the high voltage
board (HVU) if
necessary.
Go to step 2.
2
Is connector CN9 on the printer controller board
connected properly?
Replace the
printer controller
board.
Go to step 3.
Plug the
connector in
securely.
3
Did replacing the printer controller board fix the
problem?
Problem solved. Replace the high
voltage power
board (HVU).
92x Service
Toner Sensor
Step Questions/actions Yes No
1 Is the toner cartridge the correct type for the printer? Go to step 2. Recommend the
customer replace
the cartridge with
the correct type.
2
Is the toner cartridge encoder wheel dirty? Clean the
encoder wheel
and toner sensor.
Go to step 3.
3
Replace the toner cartridge for the color with the error.
Did this fix the problem?
Problem solved. Go to step 4.
4
Test the sensors.
While actuating the sensor, does the voltage fluctuate
between 0 V and +5 V between pins 1 and 4 and 5, 8
and 9, 12, and 13 on CN1 on the printer controller
board.
Replace the
printer controller
board.
Replace the
affected toner
sensor.