HP 8470 battery problem

[hazim]

I have a problem in hp 8470

Laptop work normal with charger only with out battery

When I shut down and remove charger and but the battery ( work with battery only ) laptop works on an external monitor only (black laptop screen) keyboard and touchpad completely stopped

When I shut down and remove battery and work with charger only laptop work normal

If I work with charger and battery together (black screen ) keyboard and touch stopped

Chang ram, change more than 2 new batt

I need your help Thanks a lot

[mon2]

Re: HP 8470 battery problem

Is this your board?

https://www.badcaps.net/forum/showth...highlight=8470

Remove all power. Meter in resistance mode.

Check the 2 mosfets that are being referenced in the attachment (assuming this is your logic board).

Measure the resistance across the mosfet leads as follows:

source (1-2-3) & drain (5-6-7-8)
source (1-2-3) & gate (4)
gate (4) & drain (5-6-7-8)

Post each measurement. Then repeat for the next mosfet.

If the mosfet resistance is too low, then it is possible that the mosfet is leaky.

Do read the above sticky from @Piernov - it is a must read. Often, the 2nd DCin mosfet becomes leaky and will raise a fault like this one.