Janome MC9900 Service Manual page 36

Reverse
stitch button
Start/Stop button
Needle plate is attached:
Needle plate for straight
stitch is attached:
Fig. 4
Needle plate replacing bar
4. Turn the power switch ON while pressing the Start/
Stop button and the Reverse stitch button to enter the
factory setting mode.
Press "Other sensor" key.
5. Be sure that "Straight" indicates "L", and "ZigZag"
indicates
"H" when the needle plate is attached.
6. Replace the needle plate with the needle plate for
straight stitch. Be sure that "Straight" indicates "H",
and "Zigzag" indicates "L".
If not, adjust the micro switch base plate position (see
page 33).
* To remove the needle plate, press the needle plate
replacing bar in the direction of arrow with a
screwdriver.
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