Checking The Leds; If The Run Led Turns Off; If The Err. Led Or Com.err. Led Turns On - Mitsubishi Electric QJ71E71-100 User Manual

16.4

Checking the LEDs

The following describes how to troubleshoot the problem by checking the LEDs.
The on/off status of the INIT. LED, OPEN LED, ERR. LED, and COM.ERR. LED is stored in Area for module status (address:
C8 ) of the buffer memory. (
H
16.4.1

If the RUN LED turns off

The following table lists the items to be checked and the actions to be taken if the RUN LED turns off after the E71 is
powered on.
Check item
Is it a watchdog timer error?
Is the E71 mounted properly?
Is the power capacity of the power supply module sufficient?
If the action above does not solve the problem, perform the following tests on the E71 to check for hardware error.
• Hardware test (
• Self-loopback test (
16.4.2

If the ERR. LED or COM.ERR. LED turns on

Connect the CPU module connected to the E71 with the ERR. LED or COM.ERR. LED on to a programming tool to
identify the cause. (
If the action above does not solve the problem, perform the following tests on the E71 to check for hardware error.
• Hardware test (
• Self-loopback test (
The COM.ERR. LED does not turn off even after the error cause is removed. To turn it off, refer to "How to Turn Off the
COM.ERR. LED". (
Page 37, Section 3.5.2)
Reset the CPU module and check that the RUN LED turns on. If the RUN
LED still does not turn on, the E71 may be faulty. Please consult your local
Mitsubishi representative.
Securely mount the E71 on the base unit.
Check if the power supply module has enough power capacity.
Page 374, Appendix 6.2)
Page 373, Appendix 6.1)
Page 282, Section 16.2)
Page 374, Appendix 6.2)
Page 373, Appendix 6.1)
Page 339, Section 16.8)
CHAPTER 16 TROUBLESHOOTING
Action
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