Specifications

B) Check that the UTC does not falsely signal the CHECK BOBBIN message when
thread is still on the bobbin.
1. Test for this by simply sewing with the test design. For reliable results,
embroider the design for at least 5 minutes, or about 4000 stitches at
750 stitches per minute.
2. If you get false CHECK BOBBIN messages, slightly loosen the UTC sensor
body at the screws shown in Figure 4-26, and at the slotted screw hole
(left side) move the sensor
a very small amount closer to the needle.
Re-tighten the screws.
UTC sensor
body screws
slotted
screw hole
UTC
sensor body
VIEW from UNDER the
UTC ASSEMBLY
(assembly shown removed from
needle plate support bracket,
but is actually attached during
this adjustment)
Figure 4 - 26
Sew Test 4 - 33
110291-01, Rev D 4. Trimmer Maintenance