How to get a XMC14xx running without Debugger

Hello.

I've a big problem: my XMC14xx microcontroller doesn't start the program in flash after a reset.

I've set the BMI to 0xF8C3 -> User Mode Debug enable over SWD.

Programming and debugging over SWD0 is working without problems.
The programm is working fine in debug mode or after a neu flash/program process.

But if i turn of power (and disconnecting the SWD-Interface) and turn it on again,
the microcontroller do noting, like a none existing program in flash, or a ASC-Boot strap loader...

Is there a additial secret in the Chip to start the program from flash?
I didn't configure the HWCON-Pin's for startup. The SWDIO and SWDCLK-Pins (P0.14 and P0.15) have pullup's.

The app note: Infineon-ApplicationNote_XMC1000_Microcontroller_BootModeHa ndling-AN-v01_00-EN.pdf
says: User Debug Mode -> run user code (flash)

There is no RAM-Code in my program.

Any idea?