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- HP Omen 15 dc0003la won't boot CMOS error 502

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12-06-2023 07:03 PM - edited 12-06-2023 07:30 PM
Before this issue, my computer started with a problem that it instantly woke up from sleep or restarted when shutting down, I had to power off with the shutdown button. Battery had warnings and didn't retain much charge.
Another recent upgrade was the ram, but I already tested with the old ram.
I made a bios update, but it didn't fix that issue, so I kept using it like that. Last friday when I turned it on it didn't do anything, only black screen, leds and fans on. If I press WIN + V, I can get it to show the 502 cmos error screen, but it is the only screen I can see, can't access BIOS or any other menu. Made a BIOS recovery flash drive, but I can't get past the black screen. Also tried UEFI Hardware Test, but no success, ESC key never shows anything.
I ordered a new batery, it came in today, replaced and fully charged it before trying again. With the new battery it restarted a few times but always with the black screen. And still the only screen I can see is the CMOS error screen when I press WIN + V. I don't know what else to try.
Update... I removed the ssd and now I'm able to access hardware diagnostics and recovery options.
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12-12-2023 10:52 AM - edited 12-12-2023 10:52 AM
Thanks for your help. I think the problem was caused by the battery, My bios was reset to default settings and I didn't remember I had to activate Legacy Boot for my ssd to work (don't remember why) but removing it I was able to access bios and fix it.
What I haven't been able to fix (maybe it's a hardware issue) is that when I shutdown or sleep the computer it restarts automatically. Also when playing videogames sometimes the wifi dissappears and I have to restart to bring it back.
12-09-2023 10:23 AM
Hi @amendezc ,
Welcome to HP Support Community.
Thank you for posting your query, I will be glad to help you.
May I know
1. Since when are you facing this issue
2. Have you made any changes on your PC post that this issue raised
It seems like you've already tried some troubleshooting steps, but the issue persists. Here are some additional steps you can take to troubleshoot the problem with your HP Omen 15:
Check Hardware Connections:
- Ensure that all hardware components, including RAM, are securely connected. Reseat the RAM modules and any other removable components.
- Check for loose cables or connections inside the laptop.
Remove External Devices:
- Disconnect all external devices, including USB drives, printers, etc. Sometimes, external devices can cause boot issues.
BIOS/UEFI Settings:
- Since you mentioned a BIOS update, it's worth checking if any settings in the BIOS/UEFI might be causing the issue. Reset the BIOS/UEFI to default settings and see if that helps.
Boot from a Minimal Configuration:
- Disconnect unnecessary components like additional hard drives, secondary RAM modules (if you have multiple), and any other peripherals. Try to boot with the minimum required hardware.
Run a System Diagnostics Test:
- You've already tried the UEFI Hardware Test, but it's worth running it again after making sure your hardware connections are secure.
Update BIOS/UEFI:
- If a new BIOS update is available, try updating the BIOS/UEFI again. Make sure to follow the manufacturer's instructions carefully.
Check for Overheating:
- Overheating issues can cause boot problems. Ensure that the cooling system is working correctly, and there's no dust clogging the vents.
Try a Different Power Adapter:
- In some cases, a faulty power adapter can cause issues. If you have a spare or can borrow one, try using it.
Seek Professional Help:
- If the issue persists after trying the above steps, it might be a hardware problem that requires professional attention. Consider contacting HP support or taking your laptop to an authorized service center.
Data Recovery:
- Since you've removed the SSD and can access recovery options, consider connecting the SSD to another computer as an external drive to recover important data.
Please refer this CMOS Reset(502) follow the troubleshooting steps HP PCs - 500, 501, or 502 error displays on a black screen
I hope this helps.
Take care and have a good day.
Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos/Thumbs Up" on the bottom right to say “Thanks” for helping!
A_Gayathri
HP Support Community Administrator.
12-12-2023 10:52 AM - edited 12-12-2023 10:52 AM
Thanks for your help. I think the problem was caused by the battery, My bios was reset to default settings and I didn't remember I had to activate Legacy Boot for my ssd to work (don't remember why) but removing it I was able to access bios and fix it.
What I haven't been able to fix (maybe it's a hardware issue) is that when I shutdown or sleep the computer it restarts automatically. Also when playing videogames sometimes the wifi dissappears and I have to restart to bring it back.
12-12-2023 01:28 PM
@amendezc ,
Thank you for your reply
Please try the following Troubleshoots steps.
Step 1
1. Turn off the Unit.
2. Disconnect the AC adapter.
3. Remove any discs from the disc drive.
4. Remove memory cards from the card reader slot.
5. Disconnect all nonessential peripheral devices, such as printers, scanners, external hard drives, and USB flash drives.
6. Disconnect the AC adapter press and hold the power button for approximately 15 seconds.
7. Reconnect the AC adapter, and then turn on the computer.
Step 2
Turn off the unit and please press and hold the Windows key + letter B key and the power button together for 30 seconds after 30 seconds, 1st release the power button but keep holding the Windows key and B key for ten more seconds and then release these two keys If done correctly, you will see the display flashing once. Please attempt it thrice as this step and Restart the unit
Step3
The unit has to be turned off, Press Win+ V while holding these two keys then Press the Power button, continue to hold all three keys for 30 seconds and then release the Power button first and then release these two keys Please attempt it thrice and then you may get a Pop-Up CMOS Check and it will restart the unit
Even if you don't get a Pop-up restart the unit manually after 3 attempts.
Hope this helps! Keep me posted.
Please click “Accepted Solution” if you feel my post solved your issue, it will help others find the solution. Click the “Kudos/Thumbs Up" on the bottom right to say “Thanks” for helping!
A_Gayathri
HP Support Community Administrator.