I have a Dell G3-3579 in whose battery began failing. My client (the owner) replaced the battery with a third-party battery but found that new the battery didn't charge either. I have examined the laptop's behavior.

The OLD BATTERY exhibits the following symptoms:

• LED at charging port is usually white/steady when the laptop is OFF

• LED is white/steady while the BIOS screen and the Windows login picture are shown

• LED starts blinking 4-amber-1-white when login is performed

• LED quickly changes to continuously-blinking amber and stays there until system is powered down

• Sometimes the 4,1 leading to constant amber blinking occurs shortly after plugging in the adapter

BIOS Battery Information:
     - Primary Battery  - 0%
     - Not Installed
     - AC Adapter = 130W

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With the NEW battery, the system behaves as follows:

• LED at charging port is white/steady

• The battery indicator shows that the battery status is "0% available (plugged in)"

• BIOS Battery Information
     - Primary Battery  - 0%
     - Idle
     - Health: Communication Error
     - AC Adapter = 130W

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I have tried:

• Powering down, removing the adapter and battery and pressing the power button to reset the power circuit

• Removing adapter, battery and CMOS battery and pressing the power button to reset the power circuit

• Checking the CMOS battery (3.1vdc)

• Powering up, uninstalling the battery drivers in the Device Manager, powering back up to reload the drivers

At this point I considered purchasing a genuine Dell battery but have seen a number of postings suggesting that the mainboard may be bad and I don't want to throw good money after bad. Can anyone offer a definitive diagnosis? Thanks in advance for your opinion and the time and effort you spent reading this.