Locate the two large coils near the standby IC. One should read exactly 3.3V and the other 5V as soon as the power adapter is plugged in, even before pressing the power button. Memory & System Rails ( +1.2V_Memory and +1.0V_PCH )
The LA-F952P motherboard (also referred to by the platform code ) is found in several popular Acer laptop models:
9th Generation Intel Core i5/i7 (Coffee Lake Refresh-H) la-f952p rev 1.0 boardview
Generated by the Power Management IC (PMIC / Step-Down controller). These rails power the Embedded Controller (EC) and the BIOS chip.
Search for the main DC-in jack or the first input MOSFETs (often labeled PQ series). Click on the output drain of the second MOSFET to highlight the entire primary power rail. The boardview will light up dozens of ceramic capacitors across the board. You can now use a thermal camera or voltage injection to find which highlighted capacitor is shorted to ground. 2. Missing Always-On Rails ( +3VALW / +5VALW ) Locate the two large coils near the standby IC
For micro-soldering technicians and hardware enthusiasts, relying on standard repair steps is not enough when dealing with complex multi-layered motherboards. A boardview file maps out every electronic trace, pad, component name, and test point, making it the most critical tool for diagnostic success. What is a Boardview and Why Does It Matter?
| Symptom | Suspect Component(s) | Proposed Solution(s) | Real-World Example | | :--- | :--- | :--- | :--- | | | Charging circuit (ISL88739A), Input MOSFETs (PQ306) | Check for +19V at the DC jack, then trace to the charger IC. Replace any blown MOSFET or the charging IC. Verify the charging IC's enable signals. | A client replaced a keyboard, losing the insulating layer, which shorted PC302 and PQ306, and blew the ISL88739A charger. Replacing these restored power. | | Random freezes, screen glitches | Faulty system RAM, GPU-related component | Run thorough memory diagnostics (e.g., MemTest86). If the issue persists, use the boardview to locate the GPU power management ICs and related capacitors. Visually inspect for swollen or leaking components. | A user with an oxidized board (maybe from water damage) experienced a 1-second power-on then shutdown, and the problem was never fully diagnosed, possibly due to multiple component failures. | | No display, but backlight works | EDP cable, LCD panel, LVDS circuit | This often points to a lack of image data reaching the screen. Measure the EDP lanes for voltage and clock signals. If they are present, the problem is likely the LCD panel or its cable. If they are absent, trace back to the GPU or its power management. | A forum post about a "no image" symptom mentioned that the voltage on the EDP (embedded DisplayPort) pairs was the same, which could indicate a missing data signal or a fault further down the line. | | Battery not charging, laptop runs on AC only | Battery connection, ISL88739A charger IC | First, check the physical battery connector for damage or poor contact. Test the battery in another laptop or test a known-good battery in the target machine. If that fails, the charger IC is the main suspect. | A common report: "The laptop works fine, but it won't charge the battery." Replacing the ISL88739A IC often resolves the issue. | These rails power the Embedded Controller (EC) and
Set your multimeter to Resistance mode (Ohms). Connect the black probe to a known chassis ground (like the metal shielding of a USB port or a screw hole). Use the red probe to check the resistance of all major power inductors (coils): Should be around 100+ Ohms. 3.3V / 5V Coils: Should be in the Kilo-Ohms range.
Trace the power line from the input connector pads to the first and second protection MOSFETs.