Chapter11 Troubleshooting - Mitsubishi QJ71MB91 User Manual

11
TROUBLESHOOTING

CHAPTER11 TROUBLESHOOTING

This chapter explains the details of errors and corrective actions.
11.1 Troubleshooting
(1) Troubleshooting of errors indicated by LEDs
No. Symptom
1 The RUN LED turned off.
2 The ERR.LED turned on.
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- 1 11.1 Troubleshooting
Table11.1 Troubleshooting list of errors indicated by LEDs
Check point
Check the mounting status of the
QJ71MB91.
Check the power supply capacity.
Check the programmable controller CPU
for an error.
Check for a watch dog timer error (X1F).
Check the operation mode setting value of
the intelligent function module switch.
Check the transmission setting status
value of the intelligent function module
switch.
Check the station number setting value of
the intelligent function module switch.
Check that the QJ71MB91 is not mounted
with an A-mode QCPU.
Check if the module is in the hardware or
self-loopback test mode.
Refer to "The RUN LED turned off."
Check if the automatic communication
parameter setting, error completed (X5/
XD) is ON.
Check if the MODBUS device
assignment parameter setting, error
completed (X9) is ON.
Corrective action
Switch OFF the power and remount the
QJ71MB91.
Replace the power supply module.
If the programmable controller CPU is
faulty, take corrective actions according to
the QCPU User's Manual (Hardware
Design, Maintenance and Inspection).
• Reset the programmable controller CPU
or reapply the power.
• If the problem persists even after the
reset, a possible cause is a hardware
fault. Perform a hardware test, and
replace the QJ71MB91.
Check the setting range of each intelligent
function module switch, and correct the
value.
Mount the QJ71MB91 on a Q-mode
QCPU.
• Perform the test again after checking
the mounting status of the QJ71MB91.
• If the ERR.LED turns on again, a
possible cause is a hardware fault.
Replace the QJ71MB91.
Refer to "Automatic communication
parameter setting, error completed (X5/
XD) turned on."
Refer to "MODBUS device assignment
parameter setting, error completed (X9)
turned on."
(Continued on next page)
Reference
Section 6.1
Section 3.1
-
Section 6.4.1
Section 6.6
Section 2.1
Section 6.4.1
Section 6.4.2
This section
(1)-1
This section
(2)-3
This section
(2)-4