The most common issue with MSI gaming laptops is a failure in the power delivery system. The schematic allows you to trace the from the jack, through protection MOSFETs (often labeled PQxx), to the charging IC (typically BQ24735 or similar), and finally to the 3.3V/5V regulator (PUxx). Without the schematic, you cannot verify which voltage is missing.
| Symptom | Likely Cause | Schematic Reference | |---------|--------------|----------------------| | No power, no LED | Blown DC-in MOSFET (PQ1/PQ2) | Page 2 – “DC_IN” section | | Powers on, no display | Corrupted main BIOS (U19 – Winbond 25Q64) | Page 25 – “SPI Flash” | | Short on +VCC_CORE | Dead CPU power phase (high-side MOSFET shorted) | Page 4 – “CPU VRM” | | Battery not charging | Failed BQ24735 (PU1) or sense resistor (PR3) | Page 2 – “Charging Circuit” | | Overheating / fan full speed | Damaged thermistor network (TH1/TH2) | Page 22 – “Thermal Sensor” | ms-16j91 schematic
You can find the MS-16J91 schematic diagram through various online sources, including: The most common issue with MSI gaming laptops
: This site offers a dedicated download page for various MSI motherboards, including the MSI MS-16J91 Schematic. | Symptom | Likely Cause | Schematic Reference