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Hp 840 G1/G2 How to Reset CMOS Battery

by Dariusz Dubis

Please see the attached pictures whilst following this process.

But please make sure you follow the process exactly as we list it.


1. Remove the power supply to the laptop, unplug it from the wall and the laptop its self.

2. Turn the laptop over and flick the switch which holds the laptop back panel on to reveal the battery compartment

3. Remove the battery completely.

4. Please see the attached picture showing the lead which you need to unplug " this cuts all power to the motherboard"  you must make sure at this stage that you do not pull on the red/black wires, you must only prise out the white connection block at the end of the red/black wires from the blocks housing on the motherboard.

5. Once the red/black wires have been removed, please leave them disconnected for at least 5 minutes.

6. Now reverse the process, starting with replacing the red/black wires into its housing on the motherboard.

7. Then reconnect the power pack and power up the laptop

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