JUKI LK-1900AN Engineer's Manual page 108

Trouble
From the previous page
4. Sewing machine locked
5. Severe vibration
6. Malfunction of vertical movement
of work clamp foot
Cause (1)
From the previous page
3-5) Inadequate adjustment of
the X sensor position
3-6) Inadequate adjustment of
the Y slit plate
4-1) Large needle compared
with the hole diameter of
the needle hole guide
5-1) Inadequate crank balancer
positioning
6-1) Looseness of thread trim-
mer cam screw
6-2) Presser pulse motor mal-
function
6-3) Defective circuit board
Cause (2)
4-B) Friction is excessive between the
Y feed arm and the cloth feed
support plate.
4-C) The feed plate or the work clamp
foot is caught by the needle hole
guide.
2-A) Defective the presser pulse mo-
tor.
2-B) The presser pulse motor is
wrongly connected.
3-A) Circuit board programming flaw.
3-B) Connector connections are
wrongly made.
Check and corrective measures
Install the cloth feed support plate.
Tighten the set screw further for the needle
hole guide.
Adjust the X sensor position correctly.
Adjust position of the Y slit plate correctly.
Replace the needle hole guide.
Define the correct crank balancer position.
Define the thread trimmer cam position and
fix the cam.
Replace the presser pulse motor.
Check the connector connections.
Replace the circuit board.
Check the connector connections.