https://devzone.nordicsemi.com/f/nordic-q-a/78034/custom-board-with-nrf52840-unable-to-start-application-until-swd-connectedDear Nordic team, We have designed custom boards with nrf52840 chip. We observed that in one of the boards the application is not running until the swd pins of the custom board are connected to swd connector on nrf52840 development kit. We are unableen-USTelligent Community 13Thu, 29 Jul 2021 12:30:25 GMThttps://devzone.nordicsemi.com/thread/322453?ContentTypeID=1Thu, 29 Jul 2021 12:30:25 GMT137ad170-7792-4731-bb38-c0d22fbe4515:57700c1e-952f-4185-b78d-fb803e84325eJared<p>Hi,</p> <p>What percentage of produced samples are you seeing this issue on?&nbsp;</p> <p>What voltage do you measure on the nRESET pin and on VDD on the failing samples?</p> <p>Could you share the schematic for you design?</p> [quote user=""]We observed that in one of the boards the application is not running until the swd pins of the custom board are connected to swd connector on nrf52840 development kit.&nbsp;[/quote] <p>&nbsp;You just connect the SWD pins, you do not go into debug mode?</p> <p>regards</p> <p>Jared&nbsp;</p><div style="clear:both;"></div>