Forum rules: Click here to view the forum rules
- Topic title should contain: the device's manufacturer, full model and the brief description of problem.
- Topic message should contain: the PCB marking code (required in case of hardware repairs), an extended description of problem, things you have checked/replaced/measured, your conclusions and the question. If you are not able to find the PCB marking code, please read THIS TOPIC. If you still cannot locate the PCB markings, please upload a clean, both-side photos of the mainboard - it is required to remove any films, modules or brackets possibly covering these markings.
- Before posting a new topic please read all topics in TRAININGS subforum and make a preliminary diagnostic based on the content of those trainings.
- Uploading of any complete schematics, BIOS / firmware files or any other kind of documentation, or linking to 3rd party websites with such files, is STRICTLY PROHIBITED. You can only upload the small portion of documentation or, link to BIOS file on UNVERIFIED BIOS FILES subforum, which simplifies the diagnostics/repair. You are not allowed to upload more then one complete page of instruction/schematic per single topic. The file you upload must not contain any watermarks, "confidential" markings, links or email addresses and cannot be password-protected.
- It is only permitted to describe one faulty device per single topic - you should always open a new topic for each subsequent device.
- Requesting of the full schematics, BoardView files, BIOS files or any other kind of documentation is NOT ALLOWED in this subforum. If you need to ask for any of these, you should open a new topic in DOCUMENTATION/BIOS REQUEST subforum.
This topic is marked as ARCHIVAL. Please only reply if your message contains the solution (Terms and Conditions p. 12.1).
Re: Re: HP Elitebook 840 G1 No Display
by Google Adsense [BOT] • 9 March 2024, 14:33
cygron wrote:I found U7400 pin 1,7 (PWR_GOOD) is not coming. So i try to search why on the circuit. Trace the circuits and found there is no 1.05V on Q7151 pin 4 (Source side). Drain side is ok. Only about 2.3V on Gate side. P15V0A line is about 14V on other FET (Q7050) side. R7151 (P15V0A side) has no connection on other P15V0A side. So i simply jumber the Q7151 Drain to Source and then laptop is running ok. But only one error remaining. The Laptop is booting up so slowly even using SATA SSD Hardisk. It's took about 5 minutes and up to booting. After booting up in windows, laptop aslo respond so slowly. SSD Hard disk is ok. I already tested with other SSD hard disk. I try to reflash BIOS and EC firmware but problem is still exit.
I already tried this. Jumper the pin 2 of diode D6151 to pin 1 of resistor R7151 (or) jumper the Q7151 drain to source. Whatever i do the result was the same. Laptop is running but too slow to boot (even using SATA SSD) and in windows also respond very slowly.
Voltages to groun on coils are
L6100 - 3.3V
L6150 - 5V
L6200 - 1.35V
L6000 - 0.5V (Without Battery)
L6600 - 1.7V
L6300 - 1V
L6350 - 1.5V
In BIOS setup, laptop is running ok and respond fast. Only slow when booting and in windows. I download latest bios from hp official website and flash using bios setup but problem still exit.
L6100 - 3.3V
L6150 - 5V
L6200 - 1.35V
L6000 - 0.5V (Without Battery)
L6600 - 1.7V
L6300 - 1V
L6350 - 1.5V
In BIOS setup, laptop is running ok and respond fast. Only slow when booting and in windows. I download latest bios from hp official website and flash using bios setup but problem still exit.
I think i found the problem device for slowing loading to windows. When i remove U800 (Card Rader IC) and now laptop run fast and smothly. But other problems still exit. LAN driver could not properly install and show error code 10. I already tried a lot of drivers official and unoffical. And WIFI Card is not detected.
U400 pin 4,5,15,19,29 have 3.3V and pin 8 have 0.95V. Pin 6 have ground. L400 is good. Is U400 damage?
U400 pin 4,5,15,19,29 have 3.3V and pin 8 have 0.95V. Pin 6 have ground. L400 is good. Is U400 damage?
Re: HP Elitebook 840 G1 No Display
by Google Adsense [BOT] • 17 April 2024, 11:57
This topic is marked as ARCHIVAL. Please only reply if your message contains the solution (Terms and Conditions p. 12.1).
Who is online
Users browsing this forum: No registered users and 4 guests
_______________________________All rights reserved. Unauthorised copying of this website's content or any of its part is strictly forbidden.
Any trademarks, brand names, products or services published on this website belong to their legal owners, are copyrighted and used for information purposes only.