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Service Manual STG5/7 intelligent STW5/7 intelligent form 9123999 rev. 05/2010
TROUBLESHOOTING
Description of part
Symptoms
Possible causes
Solving: checking/action
Display/CPU on operation
panel and power I/O
board
no illumination on
display
Wiring.
Check the wiring.
Check the power on the
power I/O board by the
green LED.
Fuse burned.
Check the 125 mA fuse on
the power I/O board.
Check the fuse F1 and F2.
Flat cable.
Check grey flat cable
connection.
Check functions after
connecting a new grey flat
cable.
Display malfunction.
Check power to display by
the 2 green LED’s and the
red flashing LED on the
CPU board.
Check the connectors of
the display on the display
and CPU board.
Check functions after
installing a new CPU
board with display.
Power board malfunction. Check functions after
installing a new power I/O
board.
One or more functions
don’t work or stay
activated.
Relay malfunction.
Check relay on function
with problem.
Display shows strange
things.
Parameters not on right
settings.
Check parameters.
Wrong software or loss of
data.
Check software version or
upload latest software.
Dipswitches on CPU board Dipswitch 1 + 2 = off.
Dipswitch 2 + 3 = on.