Brother DCP7010 Service Manual page 216

I-1 Light
(1) Check the printer's environment. Conditions such as humidity, high
(2) If the whole page is light, toner save mode may be on. Disable toner save
(3) Try installing a new toner cartridge or drum unit.
Possible cause
Step
Toner sensor 1
failure
(printer side)
Toner sensor 2
failure
(toner
cartridge side)
Drum 3
connection
failure
HVPS / Main 4
PCB failure
Dirt on the 5
scanner
window
Laser unit 6
failure
User Check
temperatures, etc. may cause this situation to occur.
mode within Printer Properties tab of the driver.
Check
Can printing be started
with the drum unit and
toner cartridge removed?
Is the problem solved when
4 or 5 pages are printed
after the toner cartridge is
replaced with a full one?
Are all the contacts
between the drum unit and
printer body connected
correctly?
Is the harness connection
between the HVPS and the
main PCB correct?
Is there any dirt on the
scanner window?
Is the problem solved after
replacing the laser unit?
9 -2 8
Remedy
Result
Yes Check if the toner
sensor is dirty and check
the toner sensor
connection.
Yes The wiper of the toner
cartridge is defective.
Replace the toner
cartridge.
No Clean contact electrodes
both on the drum unit
and in the printer body.
Yes Replace the HVPS or
the main PCB.
Yes Wipe it off with a soft
clean paper.
Yes Replace the laser unit.
Ground
contacts
(1), (4)
(5), (6)
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