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- HP Community
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- Notebook Boot and Lockup
- Removed battery from laptop. CMOS 502 error every boot after...

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01-18-2020 10:29 AM
Hi. After having removed the battery from the laptop and just running from the wall whenever I use the laptop, I receive a CMOS 502 error every time I boot up the laptop after having unplugged it from the wall. After displaying the error and then rebooting, the boot up process works fine, so it is not a crippling issue. It just makes the boot process take longer. Rebooting works perfectly so long as the laptop remains plugged into the wall.
I am wondering if there is any way to fix this error from occuring, or is this tied into using the laptop without it's battery. I have already updated the BIOS from the download here: https://support.hp.com/gb-en/drivers/selfservice/HP-Pavilion-Gaming-15-cx0000-Laptop-PC/20284020/mod...
I only removed the battery after updating the BIOS, so could it instead be a bad install of the new BIOS?
01-20-2020 06:03 PM
Welcome to the HP Support Community!
I reviewed your post and I understand that you are getting an error when you start the computer.
Don’t worry, I assure you I will try my best to get this sorted.
I recommend you follow the steps in the below article and check if it helps.
https://support.hp.com/in-en/document/c01443485
Let me know how it goes and you have a great day!
If you wish to show appreciation for my efforts, mark my post as Accept as Solution. Your feedback counts!
Cheers!
The_Fossette
I am an HP Employee
01-23-2020 05:25 AM
If you read my post, you would have read that I already have updated the BIOS. But I have updated the BIOS again, and nothing has changed.
The boot problem only occurs after having unplugged the laptop from AC power.
My suspicision was that this is something tied with having the battery removed from the laptop.
Are you able to tell me if this is a problem to do with having the battery removed, and if so, is there a solution?
01-23-2020 01:52 PM
Please follow the instructions in this Link: https://support.hp.com/in-en/document/c02693833 to Recover the BIOS and let me know if that helps
If the information I've provided was helpful, give us some reinforcement by clicking the "Solution Accepted" on this Post and it will also help other community members with similar issue.
KrazyToad
I Am An HP Employee
01-23-2020 02:01 PM
THERE IS NO FAULT IN BOOTING UP IF THE LAPTOP HAS REMAINED PLUGGED IN AFTER ONE UNSECCESSFUL BOOT. AM I RIGHT OR AM I WRONG IN SAYING THAT THIS DOES NOT IMPLY THAT THERE IS ANY FAULT WITH THE BIOS BUT THAT THIS INSTEAD POINTS TO A FAULT WITH THERE NOT BEING A BATTERY INSTALLED?
01-23-2020 06:07 PM
Have you tried the BIOS Recovery? If the issue persists, you need to contact HP Support for Service Options
Click on this link - www.hp.com/contacthp/ and select your Country to get the Contact details for HP Support
Thank you
KrazyToad
I Am An HP Employee