Siemens PLC program has an output and the output module does not have an output lamp does not light up, what are the causes of failure, hardware replacement failure is still there, seek expert guidance, the more detailed the more
1 Other places use the output point, such as may be reset in other places.
2 PLC module backplane (S5 or S7_300) failure, replace the backplane to confirm
3 address is correct?
Program a forced output program at the end of OB1 to confirm
3 Is the address correct?