Unable to connect j-link on nRF9160 custom board

Does anyone have some troubleshooting tips for how to test a custom board with nRF9160.

It is a new design, the schematic is based on the DK, including the j-link/swd connector.

We have a 3V3 supply.

I have been wondering about the inversion of the SWD RESET signal on the DK board so we implemented the schematic with both inversion and direct connection just to be sure. I assume connection of SWD nRESET signal to pin 32 throuth a 1k resistor with a capacitor is how it should be. 

Is the a guide on checking the CPU bootup etc...?

I have tested by J-Link on the DK by powering it through the external power connector and using the P18 connector. On the DK my J-Link interface connects.

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  • I have been looking on the reset circuit... Strange as it is copied from the development board.

    But it is clearly wrong. I have modified it to look like this:

    So a direct connection from j-link reset to the nReset. There is only the filter with a 1k (R10) and capacitor 100 nF (C12). 

    But I only measure ~ 1V on the reset pin. I have 3V3 on the VDD_GPIO pin. Looking on the data sheet I belive I should measure around 2.2V. It goes to 0V when debugger is disconnected... (VDD_GPIO still at 3V3)