Badcaps.net Forum
Go Back   Badcaps Forums > Troubleshooting Hardware & Devices and Electronics Theory > Troubleshooting Laptops, Portable, and Mobile Devices
Register FAQ Calendar Search Today's Posts Mark Forums Read

 
Thread Tools Display Modes
Old 07-20-2021, 07:50 AM   #1
Zentech
Member
 
Join Date: Feb 2021
City & State: Florida
My Country: Usa
I'm a: Knowledge Seeker
Posts: 91
Default HP Elitebook 840 G3 Caps and Power Button Blinking Doesn't Power On

After installing new battery and a 265gb nvme pcie hard drive for my laptop, I notice the laptop came on to BIOS detecting the drive and battery, after I power off the laptop, it got caught up in a boot loop, where as soon I plug the charger it will boot up (turn on fan and keyboard will light up) and then off. I remove the battery and hard drive, then connected the charger and continued to bootloop. I did a power reset by holding down power button for 20sec, didn't fix it, I hold power button for 1min. Then plug charger, and it will not power on or bootloop, now the caps key and power button come on and off (flashing). Now power, no display (during boot loop the display didn't come on) I tried reseatting the ram, and didn't fix it either. This laptop was able to boot into BIOS.
what you guys suggest?
thanks
Zentech is offline   Reply With Quote
Old 07-20-2021, 10:36 AM   #2
Zentech
Member
 
Join Date: Feb 2021
City & State: Florida
My Country: Usa
I'm a: Knowledge Seeker
Posts: 91
Default Re: HP Elitebook 840 G3 Caps and Power Button Blinking Doesn't Power On

I just started troubleshooting the board and I noticed when I press the power button the 3.3 volts do not go to ground at the connector... I circled the power button on the picture. can someone verify that is the correct power button connector?
Attached Images
File Type: jpg 20210720_120842.jpg (570.9 KB, 17 views)
Zentech is offline   Reply With Quote
Old 07-23-2021, 04:05 PM   #3
Sephir0th
Badcaps Veteran
 
Sephir0th's Avatar
 
Join Date: Oct 2020
City & State: Wangerland
My Country: Deutschland
Line Voltage: 230VAC 50Hz
I'm a: Hobbyist Tech
Posts: 269
Default Re: HP Elitebook 840 G3 Caps and Power Button Blinking Doesn't Power On

Isn't the Power Button on a seperate Board?

In this Case it can't be so hard to Figure Out whether the Power Button is working properly.

I believe there is also the Lid-Switch and it is possible you confused the Voltage Readings.

However without Checking the Sub-Board or all Pins of the connector, No progress

Easiest should be to just unscrew the Board and Check directly at the Button. Usually it will Work this way.
Sephir0th is offline   Reply With Quote
Old 07-23-2021, 05:14 PM   #4
RJARRRPCGP
Badcaps Veteran
 
Join Date: Jul 2004
City & State: North Springfield, Vermont
My Country: USA
Line Voltage: 118-127V 59-63.5 Hz-> actualizo: pérdido de voltaje
I'm a: Knowledge Seeker
Posts: 5,845
Default Re: HP Elitebook 840 G3 Caps and Power Button Blinking Doesn't Power On

Possible that the power adapter connector has a bad solder joint.
__________________
MSI B450 Tomahawk

Ryzen 7 "Matisse" 3700X

16 GB Corsair Vengeance LPX DDR4 SDRAM

MSI Gaming X Radeon RX5600XT

eVGA Supernova G3 750W

Samsung 970 Pro 512 GB NVMe SSD




"¡Me encanta "Me Encanta o Enlistarlo con Hilary Farr"!" -mí mismo

"There's nothing more unattractive than a chick smoking a cigarette" -Topcat

"Today's lesson in pissivity comes in the form of a ziplock baggie full of GPU extension brackets & hardware that for the last ~3 years have been on my bench, always in my way, getting moved around constantly....and yesterday I found myself in need of them....and the bastards are now nowhere to be found! Motherfracker!!" -Topcat

"did I see a chair fly? I think I did! Time for popcorn!" -ratdude747
RJARRRPCGP is offline   Reply With Quote
Old 07-24-2021, 01:23 AM   #5
Sephir0th
Badcaps Veteran
 
Sephir0th's Avatar
 
Join Date: Oct 2020
City & State: Wangerland
My Country: Deutschland
Line Voltage: 230VAC 50Hz
I'm a: Hobbyist Tech
Posts: 269
Default Re: HP Elitebook 840 G3 Caps and Power Button Blinking Doesn't Power On

The History from the Link Would have been useful in this original Thread...

https://www.badcaps.net/forum/showthread.php?t=97547

Why did you openened at least two Threads for this?

It could be, the 3V LDO is partially shorted. What is the Résistance to GND in Ohms, where you measured the 2.3V?

In my opinion the issue Points Into the direction of the EC/SIO.
Sephir0th is offline   Reply With Quote
Old 07-24-2021, 02:56 AM   #6
SMDFlea
Super Moderator
 
Join Date: Jan 2018
City & State: York
My Country: UK
I'm a: Knowledge Seeker
Posts: 7,951
Default Re: HP Elitebook 840 G3 Caps and Power Button Blinking Doesn't Power On

Quote:
Originally Posted by Sephir0th View Post
The History from the Link Would have been useful in this original Thread...

https://www.badcaps.net/forum/showthread.php?t=97547

Why did you openened at least two Threads for this?
That second thread is deleted now.
SMDFlea is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump



Badcaps.net Technical Forums © 2003 - 2021
Powered by vBulletin ®
Copyright ©2000 - 2021, Jelsoft Enterprises Ltd.
All times are GMT -6. The time now is 02:16 PM.
Did you find this forum helpful?