Fault Finder

Board draws 0 A, no fan spin, no boot attempt at all.

1. PPBUS_G3H voltage (expect 12.6 V)
2. PP3V42_G3H present?
3. Charger IC output rails
4. Blown fuse on PPVIN path

Won't charge, charges only on one port, slow charge, wrong wattage.

1. PPBUS_G3H — should rise with charger attached
2. Diode mode on USB-C VBUS pins
3. CC1/CC2 lines continuity
4. Charger IC gate drive signals

Machine boots (fan spin, SSD activity) but no display on LCD or external output.

1. External HDMI / Thunderbolt display test
2. eDP cable continuity
3. PPVCORE_GPU present?
4. GPU die diode mode to ground

Faint image visible with torch; display panel OK but backlight never fires.

1. PPVOUT_S0_LCDBKLT (expect 25-45 V)
2. BL_EN signal present?
3. Boost converter output in diode mode
4. Gate drive on LED driver IC

Post-spill diagnosis: corrosion tracking, shorts, intermittent operation.

1. Resistance to ground on PPBUS (expect > 50 ohm)
2. Visual corrosion under microscope
3. PP1V8_S3 / PP3V3_S5 shorts
4. Clean with IPA + ultrasonic before probing

Random shutdowns, kernel panics, thermal throttle, fan always at max.

1. Thermal paste condition on CPU / GPU die
2. PP3V3_S5 stable under load?
3. SMC thermal sensor continuity
4. RAM rail voltage (PP1V8_S3) under load