When the error message 'CMOS BATTERY FAILED' is displayed while booting up the PC, it is required to replace the battery of the motherboard of the PC in question. The CMOS battery of the system needs to be ideally replaced after every 5 years as there is depletion in the battery life of the motherboard. In addition to the CMOS BATTERY FAILED error message, the other messages include NO OPERATING SYSTEM, NEW CPU INSTALLED and DATE & TIME ERRORS. The replacement of the CMOS battery needs to be done in such a way so as to avoid any sort of unexpected issue.


If the following error message is displayed when booting up your PC,



The you can tackle this problem simply: change the battery of your motherboard.
Learn more:
Replacing the battery of your motherboard (CMOS battery)
Published by netty5. Latest update on March 19, 2012 at 07:49 PM by Virginia Parsons.
This document, titled "CMOS BATTERY FAILED," is available under the Creative Commons license. Any copy, reuse, or modification of the content should be sufficiently credited to CCM (
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