First thanks for raising this issue here in the Forum.
I answer shortly here, as I explained the issue in detail on a shooted movie. The URL link of the movie is shared in this post.
firstly, LED No.4 blicking is NORMAL. most probably is it because of a factory setting to check the I/O module. since there was not any sensor connected it was blinking to alarm users: something is missing.
As immediate as you connect the sensor it won't blick anymore. As you also shot in your video. Same here on the video I did.
Sensors LEDs will blick for another scenario! if the sensor channels are not configured( By VampSet engineering tool of V321) but the sensor is connected physically to its channel. Then again to alarm users the related LED will blink.
Last but not least, I grab your attention to the fact that any kind of sensor configuration change( enabling, disabling ...) should be updated to the V321 central unit by the VampSet engineering tool.
In the movie you shared, I/o module itself & V321 central unit both are in a faulty condition. I mean wrench LEDs are RED. the reason is you've not connected them together. It must be done by Schneider standard cable. The characteristics and ref. The numbers of these cables are available in our manuals.
To have a better understanding please take a moment to watch the video I shot. you may download it from below URL link, please.
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