HM-Sec-SC-2 doesn't report status but battery about raspberrymatic

[soosp]

Meanwhile I made more tests.

• The LED of sensors signs the open and close events, but RaspberryMatic doesn't detect it.
• If you remove a sensor from it's base, the error/saboutage event appears on the GUI so the communication is OK.

[jens-maus]

Sorry, but this can't be a general issue in RaspberryMatic since other (ten of thousands of other users) would immediately jump in here. In addition, I do have a HM-Sec-SC-2 myself and didn't notice a problem with it last time. Will try to reproduce, but I am 99% certain that this isn't an issue/bug really but rather points at some local issue in your installation only.

[PH89]

@jens-maus I can confirm exactly the same issue.

@soosp
This is what I did to make it working again:

1. Switched AES transmission back to standard. It was working fine.
2. Switched back to AES transmission. It was broken again.

Solution was to change the System-Security-Key (I was changing it already many years ago)
After reconfiguration of all my devices (AES-Key-Change) it was working again with encryption.

[jens-maus]

Thanks for the hint and testing.Perhaps @jp112sdl knows of this is an already known issue with the HM-Sec-SC-2 ?

[soosp]

@PH89 Thanks for this solution! Inspired by this, I tried an another fix:
I reset the devices to factory defaults by long pressing the config button (without removing them from RaspberryMatic), re-paired them as usual, and voila. They work again.
But unfortunately we still don't know what caused the malfunction.

[jp112sdl]

@soosp

I tried an another fix:
I reset the devices to factory defaults by long pressing the config button

This works even with a custom key? Actually the reset shouldn't work.
That's the reason why people often have problems with 2nd-hand-devices that are not completely removed with factory settings from the CCU of the original owner.

@jens-maus

Perhaps @jp112sdl knows of this is an already known issue with the HM-Sec-SC-2 ?

No, this is the first time I've heard of it for the HM-Sec-SC-2.
I believe the HM-Sec-SCo and/or HM-Sec-RHS sometimes has a similar bug, that can be solved by re-enabling AES.

But that it only works with a new key?
Hmm... I've never researched the challenge response procedure in detail.
From the AskSinPP project I know, that not only the aes key is necessary but also the key index.
Maybe not the key is broken in the EEPROM of the HM-Sec-SC-2 but the index?