HP EliteBook 840 g3 with strange problem

[classicandy]

Hi all, I have this HP EliteBook 840 g3 with a strange problem. When i power on the laptop with only the adapter/charger (without battery inserted), it powers up and displays.

If I power on the laptop with a charged battery only (without the adapter/charger), it powers up and displays also.

But if both the adapter/charger and battery are connected and i try to power on the laptop, it powers on but does NOT display and the fan spins louder than usual. And even if it manages to display after several power on and off retries, it will freeze while trying to boot into Windows.

I have tried changing chargers and battery but no luck. I have even replaced the Charger IC on the motherboard but still no luck. The charger and battery MOSFETs still seems to be ok.

Any idea what can be the cause and how to fix it?

[mon2]

Re: HP EliteBook 840 g3 with strange problem

Review the usual dcin mosfets from the power adapter.

See the above sticky by @Piernov.

[classicandy]

Re: HP EliteBook 840 g3 with strange problem

Review the usual dcin mosfets from the power adapter.

See the above sticky by @Piernov.

Laptop battery charging circuit by Piernov?

[classicandy]

Re: HP EliteBook 840 g3 with strange problem

Review the usual dcin mosfets from the power adapter.

See the above sticky by @Piernov.

I will read through and report back. Thanks

[mcplslg123]

Re: HP EliteBook 840 g3 with strange problem

Battery is charging??

[classicandy]

Re: HP EliteBook 840 g3 with strange problem

Battery is charging??

Yes, it is charging

[smali]

Re: HP EliteBook 840 g3 with strange problem

@classicandy
Clean this( mentioned in pic) Dock connector with alcohol or others cleaning materials and then gave some heat with heatgun for removing carbons and dryness... In these mb this connector making a lot of problems.