Hello @BenjaminKubitschek,
I assume the reset_b pin is reconfigured to another function too, otherwise the debugger should be able to reset the MCU and establish connection.
The JTAG/SWD/Reset_b pins are set to their default JTAG/SWD/Reset_b functions after each system reset.
The debugger can use it until it is reconfigured by the application SW.
So, you should be able to connect the debugger within this short time window.
If the reset_b pin is also reconfigured, you can power-cycle the MCU to reset it.
Something similar was discussed here (S32K144):
https://community.nxp.com/t5/S32K/S32K144-EVB-got-corrupted-after-Running-a-SDK-based-project/m-p/16...
As mentioned in the thread, PE Micro have an utility for this.
With Lauterbach, we can use a script like this
system.CPU S32K344
wait state.power()
system.attach
Somewhat related thread is below (S32K312).
The MCU was erased using J-link commander:
https://community.nxp.com/t5/S32-SDK/failed-to-power-up-dap-after-program-s32k312-with-pll0-equal/td...
Unfortunately, I'm not aware of any solution using iSystem.
I believe iSystem support should be able to help you with this.
Regards,
Daniel