The Rev 2.0 update provides better detail for diagnosing the "No Power/No Light" syndrome common on this board. PQA1/PQB12 Diagnostics:
Light on DC jack turns on, but laptop does not post or spin fan.
If you are currently working on a physical repair, please let me know:
To perform a deep-level repair or board tracing, you can access the following resources: lae801p rev 20 schematic better
Before you even hit the laptop's power button, the motherboard must be "awake" enough to look for user input. The +19V B+ rail feeds a step-down buck controller (often a dual PWM chip or separate synchronous ICs) to generate:
The LAE801P Rev 2.0 is a complex integrated circuit (IC) designed to provide a range of functions, including signal processing, amplification, and control. This IC is built with a robust architecture, ensuring high performance, reliability, and flexibility. The LAE801P Rev 2.0 is commonly used in applications that require precise signal manipulation, such as data acquisition systems, test equipment, and medical imaging devices.
Consult the Rev 2.0 schematic to identify the +3.3V_ALW and +5V_ALW coils. Low resistance (e.g., less than The Rev 2
Specialty engineering groups like the Schematics Laptop Archive Channel maintain vast repositories of freely downloadable component-level maps for mobile hardware.
HDMI, USB 3.0, RJ45 (LAN), and eDP connector for the display. 3. Common Repair Points & Issues
Laptop repair relies heavily on tracking the timing of power states (S5 through S0). Rev 2.0 explicitly clarifies timing adjustments made to the Embedded Controller (EC) and the power management integrated circuits (PMICs). This makes it significantly easier to diagnose "no power" or "power-cycling" states. Revised Protection Circuitry The +19V B+ rail feeds a step-down buck
"Parasitics," Elias muttered to himself. "It has to be parasitic inductance on the gate drive."
If you are troubleshooting a Rev 2.0 board, keep these specific component IDs and measurements in mind:
SMSC or Microchip MEC series, responsible for the power-on sequence and keyboard interface. Step-by-Step Troubleshooting with the Schematic
If you find a shorted rail but cannot see which component is failing, use a DC laboratory power supply to inject a safe, low voltage (e.g., 1V) into that dead rail. Watch the board under a thermal camera; failing capacitors or shorted MOSFETs will immediately glow hot.