2-20
5 Troubleshooting hints
5.1 Error – possible solution
The machine does not start and the control lamp on the operation
device MT800 is off – replace 10 A melting fuse; if the new fuse melts, too
or the machine does not start: replace control board KK66.
The devices will not be enabled – the motor functions but the devices like
thread cutter, foot lifting or needle cooling will not be enabled – replace 3 A
melting fuses, then cut off all devices electrically from the motor control;
switch on the machine and connect all devices one after another; after every
connection, switch on the machine and check melting fuses; in this way, the
defective device can be detected (possibly magnetic valve); if the electrical
elements of the devices are ok and the replacement of the fuses brought no
success: replace I/O-module, replace control board KK66.
The operation device MT800 is switched on, but the display is not clear
or without function – switch machine off and on; pull out the connecting
cable of the operation device MT800, check and remount it; possibly do the
same with the connecting cable between control board KK66 and I/O-module;
replace operation device MT800, replace I/O-module, replace control board
KK66.
5.2 Error messages in the display – possible solution
Fault in the control board (KG) – replace control board KK66.
External fault (KE) – switch machine off and on; check power supply; check
environment for disturbing devices (spark-generating devices, high-frequency
machines, a.s.o.).
Program defective (KP) – delete defective program and program it again; if
several programs are defective, all programs should be loaded from the
storage module; if the loaded programs are defective: replace control board
KK66.
Position actor defective (SG) – check the connecting cable of the position
actor; check the connecting cable between I/O-module and control board
KK66; replace position actor, replace I/O-module, replace control board
KK66.
Driving belt loosened (CA) – make correct belt tension; check, whether the
motor is fixed properly on the base frame.
Motor overloaded (MS) – there can be many reasons: e.g. missing oil in the
sewing head, oil too cold, possibly sewing thread wrapped around the belt
disc, ...
Motor blocked (MB) – possible causes: machine blocked, needle blocked,
...
5.3 Hints for several repair duties
Replacement of the I/O-module – the replacement of the I/O-module does
not require any adaption duties.
Replacement of the position actor – after replacement, the setting of the
needle zero position is required.
Replacement of control board KK66 – procedure: demount rear cover, pull
off four cable connectors to the control board, loosen both fixing screws, pull
off control board from the motor. Be aware to avoid damage to the electroni-
cal components; put the control board into a bag protecting it from electro-
statical load and avoid any contact to metal things. After replacing the control
board, all setup data and the sewing programs must be loaded into the
machine.
