La-d402p Schematic [better] Jun 2026

| Signal/Rail | Typical Voltage | Description | Notes | | :--- | :--- | :--- | :--- | | | ~19V | Main input voltage from DC jack. | Check first. | | +3VALW | 3.3V | Standby 3.3V rail. | Must be present for power button to function. | | +5VALW | 5V | Standby 5V rail. | Often used for USB ports. | | SUSP# (or S5_EN ) | 3.3V | Enable signal for main power rails. | Check after power button is pressed. | | +VCC_CORE | Varies (0.7V-1.3V) | CPU core voltage. | Difficult to measure; often requires an oscilloscope. |

Look for the page titled "Power Block Diagram." It visualizes exactly which buck converters create which voltages, along with their respective maximum current ratings.

The LA-D402P is a mainstream motherboard designed primarily for (including models like 15-BS010WM, 15-BS145dx, 15-BS079od). It is manufactured by Quanta (the ODM for HP), hence the "LA" prefix stands for Quanta.

: Like most Compal schematics, it is organized logically with block diagrams at the beginning and detailed pinouts for the CPU, EC (Embedded Controller), and charging ICs in the following pages. Repair Utility la-d402p schematic

Measure the gate voltage on these MOSFETs. If the gate voltage is missing, the charging management IC (often a chip from Texas Instruments or Intersil) is likely in protection mode due to a downstream short circuit.

Always disconnect the battery before probing the board to avoid accidental shorts.

A schematic is a symbolic representation of the electrical circuit. For the LA-D402P, the schematic usually runs between 40 and 60 pages, each dedicated to a specific subsystem. | Signal/Rail | Typical Voltage | Description |

Standard for modern motherboards, these rails power the Super I/O chip and the southbridge prior to the button press.

: Before assuming a motherboard failure, verify the DC jack and power adapter output. Disconnect Battery

Like many consumer-grade laptops, the LA-D402P suffers from several chronic issues: | Must be present for power button to function

Block diagram & power sequence

If the laptop turns on but immediately shuts down or does not spin the fan, the schematic allows testing the thermal management system, specifically the fan connector ( FAN1cap F cap A cap N 1 ) and thermal sensors. 4. How to Use the LA-D402P Boardview and Schematic

Uncovering the LA-D402P Schematic: A Comprehensive Guide