–105–
Checking code
Meaning, detecting method
Cause
Checking method & Countermeasure
Serial
transmission
abnormality
0403
Serial transmission cannot be es-
tablished between the MAIN and
INV boards.
1) Wiring is defective.
2) Switches are set incorrectly on the
INV board.
3) A fuse (F01) on the INV board has
been blown.
4) The circuit board is defective.
Check the connections, contact at the
connectors, and for broken wires in the
following wiring:
CNRS2 - CNRS3
CNAC2 - TB1B
SW1-4 on the INV board should be
OFF.
Find out if the fuse is blown, (if the re-
sistance between the both ends of fuse
is
∞
), replace the fuse.
If none of the items in 1) to 3) is appli-
cable, and if the trouble reappears even
after the power is switched on again,
replace the circuit board according to
the following procedures (When replac-
ing the circuit board, be sure to con-
nect all the connectors, ground wires,
etc. securely).
1
If serial transmission is restored af-
ter only the INV board is replaced,
then the INV board is defective.
2
If serial transmission is not restored,
reinstall the INV board and replace
the MAIN board. If serial transmis-
sion is restored, the MAIN board is
defective.
3
If serial transmission is not restored
by peforming both procedures
1
and
2
above, replace both boards.
[3] Self-diagnosis and Countermeasures Depending on the Check Code Displayed
(1)
Mechanical