Changing The Buttonhole Sensor - Pfaff expression 2014 Service Manual

38. Changing the buttonhole sensor

Note:
The buttonhole sensor is only exchanged complete.
Removal:
Remove the machine's mains lead.
Remove the needle and presser foot.
Remove the folding cover.
Unscrew and remove both torx screws from the housing insert.
Remove the housing insert.
Raise both lugs 1 slightly and remove the facing panel of the front housing panel.
Place the machine on its back.
Unscrew and remove the three screws in the base plate.
Tilt the base plate to the front and remove both connection plugs 3 and 4 from the circuit board
(fig. 108).
Unscrew and remove both screws 5 from the free-arm cover (fig. 109).
Bring the feed-dog lowering mechanism into its normal working position.
Disengage both feed regulators 6 using a small screwdriver (fig. 109).
Remove the cable clip.
Remove connection plug 16 from the circuit board of the front housing panel and pull the cable
downward (fig. 110).
Remove the free-arm cover from the housing to the left.
Remove connection plug 13 from the circuit board of the front housing panel and pull the cable
downward (fig. 110).
Remove cable guide 20 (fig. 109).
Dismantle buttonhole sensor 138 complete with the spring.
Fitting:
Install buttonhole sensor 138 complete with the spring.
Insert the cable with cable guide 20 in the housing.
Turn the machine upside down.
Place the cable, using a spring hook, between the motor and the housing wall.
Mount connection plug 13 on the circuit board of the front housing panel (fig. 110).
Put the machine in its working position.
Mount the free-arm cover carefully and secure with both fastening screws 5.
Bring the feed-dog lowering mechanism into its normal working position.
Engage both feed regulators 6 (fig. 109).
Turn the machine upside down.
Place the cable, using a spring hook, between the motor and the housing.
Mount connection plug 16 on the circuit board of the front housing panel (fig. 109).
Attach the cable clip.
Mount both connection plugs 3 and 4 on the circuit board of the base plate (fig. 108).
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