Digital inputs not affecting/showing in software S7-300

[Callicantzaro 0]

Hello all So I have the following problem: Several digital inputs (all in the same section) aren't working in the program. The inputs are physically connected and the diodes on the PLC are showing high which in this case they should be. However in the software reads them as low. For example: I1.4 is connected and diode is showing high, in the program I1.4 is low. As far as I can see the hardware setup is correct and so are the addresses. I have a second installation here with the exact same hardware and software which is working fine. Anyone have any ideas what could cause this?

[mechatronic_hieu 1]

You need to set "size of the process -image input area" in your HW configuration. Your input address should be inside the range what you put in HW conf.

[dekor 12]

Please check the voltage value Must be on corect range for "1" logical level

[Bryll 31]

Is the I/O unit the last one in your rack? If you have any I/O units to the right of the not working, are they working ? It can be that someone forgot the rack connection between the modules when they where installed. Another thing, is the CPU in run mode ? No fault LED's on the CPU lit ? What software are you using ? Edit: Sorry, just noticed it was an old post. Suspects that the problem is solved by now Edited 3 Dec 2015 by Bryll