Hp dv4 power supply diagram - HP Computers & Internet

Power Supply is the AC adapter (Charger), the DC Power Jack harness it plugs into in the laptop, and a power sensor chipset, or chipsets, on the motherboard.

[ Chip and Chipset are slang terms for I.C.
Integrated Circuit,

http://en.wikipedia.org/wiki/Integrated_Circuit ]

As for a diagram of how the Power circuit runs on the motherboard, it isn't available to the general public. It is part of HP's, and/or the motherboard manufacturer's, design patent.

All I can state, is that you may want to check out the continuity, of the DC Power Jack harness. (Ohms check of each individual wire)
See if it is good. Also make sure it it plugged in tightly to the motherboard.

Past this point it's check out the motherboard with a dual trace oscilloscope. Trace the power circuit down to see where the problem is.

Bad power sensor chipset? Usual repair is to just replace the motherboard. Cost, and obtain ability of procuring the chipset, plus technique, and tools involved, justifies replacing the motherboard, and not trying to replace just the chipset.

The chipset is mounted to the motherboard via a BGA Surface mount.

BGA Surface mount:
Compare to an older Intel Pentium 4 processor, that uses a Socket 478 processor socket.
The bottom of the Processor chipset has contact pins. 478 of them.
The processor socket has matching socket holes. 478 of them.

With a BGA Surface mount, there are no contact pins, nor matching socket holes.
Solder Balls take the place of the contact pins on the chipset.
Copper Pads take the place of the socket holes on the motherboard.

The chipset is set into place over the motherboard, with the Solder Balls lining up on the Copper Pads.
The chipset is set down into place, and heat is applied.

Heat is applied at a specific temperature, and for a specific amount of time. The solder balls melt, which solders the chipset to the copper pads. (Which in turn solders the chipset to the motherboard)

To replace, a BGA Rework Machine should be used. Not something everyone has laying around. Read - Expensive.
Therefore repair is expensive.

Justifies motherboard replacement.

http://www.insidemylaptop.com/disassemble-hp-pavilion-dv4-laptop/

http://www.tim.id.au/blog/tims-laptop-service-manuals/#toc-compaqhp

HP Pavilion and blue - dv4

For additional questions please post in a Comment.
I would like to know what specific problem you are having, also.

Regards,
joecoolvette