: On the LA-C391P, the code PU302 typically refers to a Power IC; troubleshooting often involves checking if the surrounding capacitors are shorted to ground. HP ZBook 17 G3 APW70 LA-C391P REV 1B BIOS Dump
When the power button is pressed, the motherboard moves from an ACPI S5 (Shutdown) state through S3 (Sleep) to the S0 (Fully Operational) state. The schematic dictates a strict handshake protocol between the Embedded Controller and the SoC.
If you have a non-working board, use a multimeter in continuity mode:
Would you like guidance on tracing a specific part of the board (power, audio, or display)? apw70 lac391p schematic portable
: To measure electrical voltage and resistance on the board.
Missing secondary power rail or a short circuit on a run rail (+3V, +5V, or VCC_CORE).
Leave a comment below or join the discussion at r/AskElectronics. Your contribution helps the entire repair community keep portable electronics out of landfills. : On the LA-C391P, the code PU302 typically
If you are currently diagnosing a specific issue on an APW70 LA-C391P board, please share the you are seeing (e.g., completely dead, spins fan but no display, amber charging light blinking) or any voltage measurements you have already taken on the main coils. Share public link
: Broadwell-U (Intel 5th Generation Core i3/i5/i7) onboard CPUs.
Tracing the schematic from the driver transistors to the output connector will reveal the current limiting resistors. These are common failure points if the output jack is shorted. If you have a non-working board, use a
If you need help tracking down a specific component on your board, tell me the (like PQ302 or PU101) or describe the exact power symptom your device is experiencing. Share public link
As the backbone of a high-performance portable workstation, this motherboard is designed to be robust and feature-rich.
For detailed repair, technicians often search for this board on specialist databases like to find confirmed BIOS files and boardview diagrams. on this board or the full PDF schematic for a circuit repair?
: It holds thousands of tiny components, including the main processor, memory slots, and dedicated graphics cards. Why You Need the Schematic Diagram