# PMIC and Board Power Up Sequence

The FS26 onboard PMIC by default implements a challenger window watchdog that will reset the S32K344 MCU continuously if the challenge is not handled in software.

To avoid this, the FS26 must be put into debug mode. This is done manually by removing the JP1 and then supplying exactly 12.0V on P27 or P28 and then inserting the JP1 jumper.

<figure><img src="/files/agNoYR2vyBwVVxs8z1h4" alt="" width="393"><figcaption></figcaption></figure>

After this is done, the reset LED D24 should no longer blink and the S32K344 will not be reset continuously by the FS26.


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