Brother TD-4000 Service Manual page 123

(5) Check the Cover Sensor (Cover sensor check)
Inspect whether the cover sensor works correctly.
1) Click the "Cover sensor check" button.
2) Open and close the top cover of the machine. The message in the "Results"
column is changed to "off" or "on". If the states of "off" and "on" are detected,
"Undo" in the "Results" column is changed to "Done".
Figure 15. Cover sensor of "off" and "on" states
3) If the "Cover Sensor 0" and "Cover Sensor 1" are changed to "Done", click the
"Quit sensors check" button to finish the inspection. If "OK" appears, the
inspection is completed correctly.
The judgement is "OK".
Figure 14. Check the cover sensor
If the states of "off" and "on" are
detected, "Undo" is changed to "Done".
If open and close the top cover,
the message is changed to "off" or "on".
Figure 16. Check the cover sensor
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