Hi @jrc6282
Try a full power refresh by removing ''all'' the power from the laptop i.e. charger, main battery and RTC battery.
The RTC battery is a coin cell battery inserted in a battery holder on the motherboard. It is usually a CR2032 Lithium battery (the battery type is marked on battery itself).
So here’s the procedure:
a. Disconnect the charger if connected.
b. Disconnect the main battery.
Here’s the [http://h10032.www1.hp.com/ctg/Manual/c05228250|maintenance and service guide] for the laptop, taken from this [https://support.hp.com/us-en/product/hp-pavilion-15-au100-notebook-pc/12499208/model/12780759/manuals|webpage]. Go to p.31 to view the necessary pre-requisite steps and then the procedure to remove the battery. ''You don’t have to remove the battery, just disconnect it.''
''c.'' Remove the RTC battery - (Remember the orientation of the battery, +ve is on top)
Go to p.51 to view the location of the RTC coin cell battery on the image of the systemboard. Also if you have a DMM (digital multimeter) use its’ Voltmeter function to test the battery’s voltage when it’s removed from the motherboard. If it is <2.6V DC replace it. The battery is a common battery available most everywhere. If it is <2.6V DC the BIOS ''can'' become corrupted preventing a normal start as the RTC battery maintains the BIOS settings when the laptop is switched off.
d. Press and hold the laptop’s Power button for 30 seconds and then release
e. Reinsert the RTC battery (note the orientation is correct)
g. Reassemble the laptop and reconnect the main battery as late as possible before closing up.
h. Connect the charger and then try to turn on the laptop.
If it starts there may be a message regarding the date and time being incorrect. This is normal as the BIOS has been reset. Once it has been corrected, the message won’t appear the next time that the laptop is started.