3.3V Regulator Checks

t he ic just above the audio ic (labelled en xx), is the 3 3v regulator t he en chip receives the vsys power (from the bq24193 chip) it outputs 3 3v when working it has an output limit of about 150ma, so if something on the 3 3v rail is shorting out, you will not see a dead short current draw testing for shorts if there is a short on the 3 3v rail, the output would be 0 5v or less for example, so it may not be a faulty regulator to test for shorts on 3 3v rail, solder a wire to ground, and a wire to the 3 3v out capacitor or test pad and use your bench power supply to inject 1v into the rail if it draws more than 0 1a then you likely have a short somewhere on a component connected to the rail use a thermal camera or ipa fluid or a resin pen to look for the shorts components connected to the 3 3v rail these are the current known components that are connected to the 3 3v rail and could be shorting it out p13usb usb chip m 92t36 power delivery chip bluetooth/wifi module there may be more components so far unconfirmed such as emmc and smaller regulators that are connected to this rail too i will update this list as i confirm them