
6 - 100
(7) Self-diagnostics list
The following table shows the self-diagnostics performed by the CPU module.
To check the error messages in the "Error message" column of Table6.29, select [Diagnostics] [PLC
diagnostics] of GX Developer.
: Self-diagnostics is performed. : Self-diagnostics is not performed.
(To the next page)
Table6.29 Self-diagnostics list
Diagnostics Error message Diagnostic timing
CPU
module
status
LED status
Q00UJ
CPU
Q00U
CPU,
Q01U
CPU
Q02U
CPU
QnUD(H)
CPU
Built-in
Ethernet
port QCPU
RUN ERR.
Hardware
failure
CPU error MAIN CPU
DOWN •Always Stop Off Flashi
ng
END instruction
not executed
END NOT
EXECUTE
•Execution of the
END instruction Stop Off Flashi
ng
SFC program
execution error
SFCP. END
ERROR
•Execution of a
SFC program Stop Off Flashi
ng
RAM check RAM ERROR •Power-on/reset Stop Off Flashi
ng
Operation circuit
check
OPE.CIRCUIT
ERR.
•Power-on/reset
•Execution of the
END instruction
Stop Off Flashi
ng
Fuse blown*1 *2 FUSE BREAK
OFF •Always Stop/
continue Off/on Flashi
ng/on
I/O interrupt error I/O INT.
ERROR
•Occurrence of an
interrupt Stop Off Flashi
ng
LAN controller
failure
LAN CTRL.
DOWN •Power-on/reset Stop Off Flashi
ng
Intelligent function
module error *1
SP.UNIT
DOWN
•Power-on/reset
•Execution of the
FROM/TO
instructions
•Execution of the
intelligent
function module
dedicated
instruction
•Execution of the
END instruction
Stop/
continue Off/on Flashi
ng/on
Control bus error CONTROL-
BUS ERR.
•Power-on
•Execution of
END processing
•Execution of the
FROM/TO
instructions
•Execution of the
intelligent
function module
dedicated
instruction
•Always
Stop Off Flashi
ng
Momentary power
failure AC/DC DOWN •Always Continue On Off
Multiple CPU high
speed bus error
MULTI-C.BUS
ERR. •Power-on/reset Stop Off Flashi
ng