30. Changing the base circuit board
Note:
The base circuit board is only exchanged as a complete unit.
Removal:
•
Remove the mains lead from the mains socket and from the machine.
•
Remove the detachable work support.
•
Unscrew and remove the three fastening screws on the base plate.
•
Tilt the base plate to the front.
•
Remove the connection plug of 12-wire flat cable 4, remove 6-wire flat cable 5 and motor cable 6
from the circuit board (fig. 72).
Fitting:
•
Set the new base plate complete against the machine.
•
Mount three connection plugs 4, 5 and 6 on the circuit board.
•
Fold the base plate against the machine and secure it with the three screws.
•
After a running-in time of 10 - 15 min. check the adjustment of equal forward and reverse stitch length
in accordance with section 22 of the service manual.
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