User`s manual

Error code list Troubleshooting
MELSEC System Q, Hardware 11 – 27
1010
END NOT EXECUTE
Entire program was executed without the execu-
tion of an END instruction.
– When the END instruction is executed it is
read as another instruction code, e.g. due to
noise.
– The END instruction has been changed to
another instruction code somehow.
 Collateral information

Common Information: —
 Individual Information: —
 Diagnostic Timing
When an END instruction executed
– Take noise reduction measures.
– Reset the CPU module and RUN it again. If the
same error is displayed again, this suggests a
CPU module hardware fault.
Contact your local Mitsubishi representative.
OFF Flicker Stop )
1020
SFCP. END ERROR
The SFC program cannot be normally terminated
due to noise or other reason.
 Collateral information

Common Information: —
 Individual Information: —
 Diagnostic Timing
When SFC program is executed
– Take noise reduction measures.
– Reset the CPU module and RUN it again. If the
same error is displayed again, this suggests a
CPU module hardware fault.
Contact your local Mitsubishi representative.
OFF Flicker Stop Q00J/Q00/Q01
(Function
version is B or
later)
QnPH
QnU
1035
MAIN CPU DOWN
Runaway or failure of CPU module or failure of
main CPU
– Malfunctioning due to noise or other reason
– Hardware fault
 Collateral information

Common Information: —
 Individual Information: —
 Diagnostic Timing
Always
– Take noise reduction measures.
– Reset the CPU module and RUN it again. If the
same error is displayed again, this suggests a
CPU module hardware fault.
Contact your local Mitsubishi representative.
OFF Flicker Stop QnU
1101
RAM ERROR
The sequence program storing program memory
in the CPU module is faulty.
 Collateral information

Common Information: —
 Individual Information: —
 Diagnostic Timing
At power ON/ At Reset/ When an END instruction
executed
– Take noise reduction measures.
– Reset the CPU module and RUN it again. If the
same error is displayed again, this suggests a
CPU module hardware fault.
Contact your local Mitsubishi representative.
OFF Flicker Stop )
1102
RAM ERROR
– The work area RAM in the CPU module is
faulty.
– The standard RAM and extended RAM in the
CPU module are faulty.
 Collateral information

Common Information: —
 Individual Information: —
 Diagnostic Timing
At power ON/ At Reset/ When an END instruction
executed
OFF Flicker Stop
Error
code
Error contents and cause Corrective action
LED status
CPU
status
Corre-
sponding
CPU
RUN ERR.
Tab. 11-3: Error code list (1000 to 1999) for PLC CPUs of MELSEC System Q