(LCD connector), JUSB1 , JHP1 (audio jack).
Use these coordinates to locate components on the schematic pages.
When troubleshooting this board, the schematic helps you navigate several critical "power rails" and logic circuits. 1. The Power Input Circuit (DC-IN)
Search for PBTN_OUT# or ON/OFFBTN# . Trace it from the physical power button board connector to the pin on the EC chip to verify if the hardware signal changes state (from 3.3V down to 0V) when pressed. Conclusion la-9413p rev 1.0 schematic
For the , always try to get the Boardview (.BRD or .CAD) alongside the PDF schematic. It shows:
The system uses an SPI flash memory chip (typically an 8MB chip like the Winbond 25Q64). If the laptop turns on with spinning fans but displays a black screen (No POST), the communication lines ( SPI_CLK , SPI_SI , SPI_SO , SPI_CS# ) between the BIOS chip and the CPU/PCH should be verified using an oscilloscope or logic analyzer. Common Faults and Troubleshooting on the LA-9413P Board
Troubleshooting a dead LA-9413P always begins with checking the power rails. The motherboard transitions through several power states: . Primary Power Rails (Always On) (LCD connector), JUSB1 , JHP1 (audio jack)
Legal and safe sources include:
chips, which handle power management, keyboard inputs, and thermal monitoring Power Sequence : The schematic includes a detailed Power Sequence Block Diagram
: Sites like Badcaps.net often host various Compal schematics (such as the related LA-9591P or LA-8241P) that may share similar power rail structures. Conclusion For the , always try to get the Boardview (
What is the board showing (e.g., completely dead, fan spins but no display, loops on power)?
The is a motherboard designed primarily by Quanta Computer (the "LA" prefix denotes Quanta) for Hewlett-Packard (HP) and Compaq brands. The "Rev 1.0" indicates the first production revision of this board.
If you do not measure ~19V at the current sensing resistor ( PR302 or equivalent), check the gates of the entry MOSFETs. Shorted ceramic capacitors on the +B rail frequently pull this line to ground. Stage 2: Always-On Power Rails ( +3VALW and +5VALW )