Chosen Solution
Hi, Dropped A1586 here that had a short on PP3V0_NAND. faulty cap located and replaced. Device now boots up with no image on the screen. PP6V0_LCM and PP_5V7 next to this are ok. There is backlight but I’m wondering because the PMIC did get very hot before the initial NAND short was removed, the adjacent Oscar gets hot now. I’m wondering what would be the next thing to test/look for?
The first thing to do is to properly probe (and compare to known-good) the Chestnut circuit as that is responsible for display and Touch. Also probe the LCD and Digitizer FPC connector against a known-good to see if other rails and signals are problematic. Then I would start probing the main outputs from the PMIC to see if one of them is shorted. This can cause a cascade of effects as most circuits also use other power lines, especially the 1V8 line.
