Hello all,

I am trying to repair the above Samsung laptop which just produces a series
of clicks when you press the power button? I have tried powering up without
the battery and removing any residual capacitor charge by depressing the
power button for 1 minute with neither the battery nor the AC adaptor connected.

The battery seems to be charging which indicates that the main 19V input
rail is functional.

Looking at the LA-8862P PCB schematic for the laptop, I cannot seem to work
out what the B+ voltage rail is and where it is generated?

Also, there is mention of a TPS51125 in the Power Tree block diagram but
it does not appear in any of the circuit schematics later on?

Any pointers would be much appreciated.

Thanks.