First rule out solder bridges and stray pieces of wire on your board. ?My experience in this kind of short on a QMX main board is that it’s from a failed chip. ?5V is supplied to the chips in the receive path (mostly), a few capacitors and the display. ?Remove the display first to rule that out. ?Then it’s a matter of elimination. ?Once you find the fault, then you have to ask why. Chips don’t fail without a reason.
