When a broken NM-C561 board lands on your desk, follow this structured diagnostic routine to locate the fault quickly: Step 1: Visual Inspection
of this schematic, such as the power-on sequence or the charging circuit?
If the laptop shows no signs of life and draws 0.00A on a bench power supply, the primary 3.3V/5V controller (often a RT8243 or SY8286 type chip) may be damaged or missing its enable signal.
Lenovo Ideapad 3 (15ARE05) Laptop Repair Guide: NM-C561 (GS44B/GS54B) Schematic Analysis gs44b gs54b nm-c561 schematic
A: The board itself is nearly identical (GS44B/GS54B NM-C561), but there may be hardware or firmware differences. Some technicians have found that BIOS dumps for the S145 do not work correctly on the V15-IKB.
If you discover a short circuit on a major power rail, set your variable DC laboratory power supply to a low voltage (always start at 1V to prevent destroying delicate logic lines) and limit the current to 1A. Inject this voltage onto the shorted rail. Use a thermal imaging camera or isopropyl alcohol to watch for the exact component that heats up instantly. Replace that component. 5. Safety Protocols for Component-Level Repair
For those interested in exploring further, here are some additional resources: When a broken NM-C561 board lands on your
Lenovo Ideapad 3-15IML05 (GS44B/GS54B NM-C561) Motherboard Schematic & Boardview Guide
The "Always-On" power rails. Generated by a dedicated step-down PWM controller immediately after connecting the power adapter. These rails power the Embedded Controller (EC) and the power button circuit. If these are missing, the laptop will exhibit completely "dead" behavior. Secondary and Core Rails (Post Power-Button)
The NM-C561 motherboard is designed to support 8th generation Intel Core processors (like the i3-8130U and i5-8250U) but may also be found with 7th generation CPUs (i3-7020U) in the Lenovo V15-IKB. It was produced by Lenovo's ODM partner, LCFC (Lenovo China Feng Chuan). Some technicians have found that BIOS dumps for
If +3VALW is missing, the laptop will exhibit no signs of life, no charging LED, and will not respond to the power button. 3. Power-On Sequencing and Signal Flow
Supports both UMA (Integrated Intel Graphics) and DIS (Discrete Nvidia N16S-GTR/N17S-G1 + GDDR5) models. EC (Embedded Controller): ITE IT8586E. Components of the GS44B/GS54B Schematic
Faulty MOSFETs are a frequent cause of power failure; if 19V is missing at the drain, the component likely needs replacement. Where to Find Files