Situation
A HP Elitebook notebook is not booting and just blinks every five seconds or so (keyboard backlightning, buttons, LEDS, screen...).
Things to try out
A few things to try out. They're variations of trying to make the computer boot with or without the battery etc.
Alternative 1
- We will try to start the notebook in BIOS recovery mode.
- Make sure the notebook is powered off.
- Press and hold the Windows and B buttons, while pressing the power button.
- If the computer starts, it should automagically show a BIOS recovery screen. Proceed as instructed on-screen.
Alternative 2
- Make sure the notebook is powered off.
- Unplug the notebook from the PSU.
- Remove the battery.
- Press and hold the power button down for twenty seconds.
- Try powering on.
Note! Do not connect the battery or PSU!
Residual power may remain, so it may actually power on or at least try. - If the computer powers on now, put the battery back and see what happens.
Alternative 3
- Make sure the notebook is powered off.
- Unplug the notebook from the PSU.
- Press and hold the power and mute buttons for about twenty seconds.
- Release the buttons.
- Connect the PSU.
- Press the power button.
- If the computer starts - good. If it doesn't, remove the battery and repeat from step 1.
Alternative 4
- Try a different PSU, plug it in and let charge for a while. Try powering on now.
- Try a different battery, replace it in and let charge for a while. Try powering on now.
Alternatives worth trying or keeping in mind
- Keep mobile phones away from the notebook, specifically close to the touchpad. It has been reported that the CPU-shieldning is non-existent. It may mess around with your computer generally speaking.
- ...
Still nothing?
- If neither of the above helps, call the HP-support for a possible motherboard replacement.
- No warranty left? Check eBay for used motherboards, or look into buying a new laptop...
Sources
https://www.reddit.com/r/techsupport/comments/740gej/hp_elitebook_840_g3_wont_turn_on_no_lights/
