iBoot DC Power Supply Battery Connector Squid-- UPDATED FOR iPHONE 14 SERIES
This cable is the "least crappy" of all the similar Chinese-made cables we've tried. The convenience can't be beat for using your DC power supply to troubleshoot "no power on" problems in iPhones. Connect the cable to your DC power supply, set the voltage to battery voltage, and then use the right adapter on this cable to connect to your device. Once you prompt to boot you can see if your device is consuming high current (i.e. short circuit), low current (i.e. dead chip/bad data line), or shows the normal signature current consumption 'heartbeat' of a device that is alive.
This cable set comes with adapters for iPhone 6 through iPhone 14, as well as Samsung, so you can work on all modern devices with one cable.
* Note the polarity of the battery connector for iPhone 12 and newer. You may need to reverse the leads for some models.