Brother 1240 Service Manual page 153

I-9 White vertical streaks
(1) Try to wipe the scanner window with a soft cloth.
(2) The toner cartridge may be damaged. Install a new toner cartridge.
(3) Check the printer's environment. High temperature and high humidity conditions
can cause this problem.
(4) Damp (wet) paper might be used. Try to change to freshly unpacked paper.
Possible cause Step
Transfer failure 1
Condensation 2
I-10 White horizontal stripes
(1) Check the paper used meets the recommended paper specifications. A rough
surfaced paper, damp paper or thick media can cause the problem.
(2) Check that the appropriate media type is selected in the printer driver.
(3) The problem may disappear by itself. Try printing multiple pages to clear this
problem especially if the printer has not been used for a long time.
(4) The drum unit may be damaged. Install a new drum unit.
Possible cause Step
Developing bias 1
contact failure
User Check
Check
Is the transfer roller scratched?
Has condensation occurred
inside the printer?
User Check
Check
Are the developing bias
contacts between the printer
body and toner cartridge dirty?
Result
Yes Replace the drum unit.
Yes Try to print several pages or
leave the printer 2 hours to allow
it to reach room temperature.
Result
Yes Clean the electrodes
at both sides.
6-31
CHAPTER 6 TROUBLESHOOTING
Remedy
Ground
Remedy
contacts