Monday, September 15, 2025

Laptop turns on (power LED lights), then shuts down in 2 seconds.

 










Step-by-Step Fixes for HP Envy x360 Convertible

1. Hard reset / Power drain

  1. Disconnect the charger.

  2. If the battery is internal (most x360 have internal), press and hold the power button for 30–40 seconds.

    • This drains static electricity.

  3. Plug the charger back in (do not press the power yet).

  4. Now press the power and check.

2. Battery vs Charger test

  • Disconnect the charger, try only on the battery.

  • Then try only on charger (internal battery is not removable without opening, so we simulate by: power off, connect charger, hold power + mute button for 15s to reset embedded controller).

  • If it works only on the charger, → battery is faulty.

  • If it works only on battery, → charger is faulty.

3. External Display test

  • Connect an HDMI monitor or a USB-C to a display adapter.

  • If the external display shows BIOS but the internal screen stays black before shutdown, → display cable / LCD issue.

4. Reseat RAM & SSD

 On HP Envy x360 Convertible:

  • RAM is often soldered (cannot be replaced).

  • But the SSD is replaceable.

Steps:

  1. Unscrew the back panel (Torx T5 usually, hidden screws under rubber feet).

  2. Disconnect the battery cable from motherboard.

  3. Remove the SSD and reinsert.

  4. Reconnect the battery, and try powering on.

5. BIOS/CMOS reset

  • HP Envy has a built-in BIOS reset combo:

    1. Hold Win + B, then press and hold the power button.

    2. Release power after ~3 seconds, keep holding Win + B until the BIOS recovery screen appears.

  • If it doesn’t, disconnect the internal battery for 10 minutes (requires opening the back cover).

6. Signs of deeper issues

  • Fan spins then cuts off → thermal/CPU problem.

  • No fan spin at all, only light flash → motherboard power circuit fault.

  • Caps Lock / Num Lock LED blinking → HP error codes (we can decode the blinks).

 Advanced Solution (if basics fail)

If none of the above helps:

  • Likely motherboard VRM, MOSFET, or BIOS corruption issue.

  • For this, board-level repair (reprogram BIOS chip or replace faulty MOSFETs) is needed in the repair lab.

 So, first try:

  1. Hard reset.

  2. Charger test (try another HP USB-C charger).

  3. Attempt BIOS reset (Win + B + Power).

  4. If it still fails → open the bottom cover, disconnect battery, reseat SSD, reconnect battery, and retry.