Mitsubishi Electric Melsec QJ71LP21 Reference Manual page 120

4 SETUP AND PROCEDURES BEFORE STARTING THE OPERATION
RUN MNG
T.PASS D.LINK
SD RD
ERR. L ERR.
4 - 14
(3) Starting a test/checking the result
The self-loopback test is executed when the CPU module is powered on from off
or reset.
Check the status by the indicator LED of the network module.
The T. PASS LED flashes during the test.
When the T. PASS LED flashes 20 times (approx. 10 seconds) or more and the
ERR.LED does not flash, this condition indicates normal completion.
If the test is abnormally completed, the ERR. LED flashes.
Upon detection of an error, the test will be terminated (abnormal completion).
Before test

T.PASS : Off
If a test has completed abnormally, check the error detail by GX Developer and
locate the error in the following method.
Network system
Optical loop system
Coaxial bus system
Twisted bus system
REMARKS
Testing status and the result can be checked in the following link special registers.
Baton pass status (host)
Cause of baton pass interruption
Offline test execution item/faulty
station (requesting side)
Offline test result (requesting side)
For details of how to check the error contents, refer to Chapter 8.
During test Normal completion of test

: Flashing : Flashing 20 times (approx. 10 seconds) or
more
Abnormal completion of test
ERR. : Flashing
SW0047
SW0048
SW00AC
SW00AD
MELSEC-Q
Checking method
Replacing the cables
Replacing the terminating registers
Replacing the module
1F : Offline test
H
2 : Offline test
H
7 : Self-loopback test
H
0 : Normal
1 or larger : Error code
4 - 14