HP DV6500 (dv66550ec) wont power on dc jack

[scobie_21]

Hi Im working on this model an it will work with charged battery but wont power on with just adapter.I have tried the following.

(a) I have tested the dc board on another dv6 both the charger and board work fine.
(b) I have removed the ram and replaced with it know good stick.
(c) I have noticed that there is 3v on all pins of pq37 but on the working mb there 1.3 I dont have a schematic for this.
(D) PC198 has what looks like dust or line around the bottom but its reading the same as the good board.

Any Ideas?

[scobie_21]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Anybody know where to get a schematic for this model please?

[scobie_21]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Not getting much help here am I doing something wrong??????

[momaka]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Not getting much help here am I doing something wrong??????

No, you're good. I'm guessing no one just saw your thread or no one knows what the problem might be.
As I stated in one of your other threads a bit earlier, pictures of your boards will give us an idea of what we are looking at. It's possible that most people here haven't worked with your board before but may be able to provide help just based on the pictures you provide.

[scobie_21]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Thanks for the reply. Im not sure what to take pictures of there's no obvious damaged components that I can see, I am not really familiar with the basic principles of troubleshooting motherboards as I dont have any experience with them and am not sure where to start.I have worked on audio equipment servicing but have been out of the game a long time.

again thanks for your time.

[momaka]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Im not sure what to take pictures of there's no obvious damaged components that I can see

Well, if the laptop is working fine with a charged battery, then obviously the majority of the motherboard is okay and only the circuit that's responsible for charging the battery/using the AC adapter is faulty.

It's usually best to take a picture of the whole board so that people can see where various boards and components are connected, then a picture of the area where the AC adapter plugs in. I'm guessing this will also include the "DC board".
Also, I doubt you'd find a schematic. When laptop is not powering from the AC adapter, standard procedure is to start at the AC adapter plug and then follow/check the circuit down from there.

[scobie_21]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Thanks for the Help, upon closer inspection I found a couple of components blown down near the Sata connector. I was able to identify the Pq27 as a 1Mz2 I think , but I cant seem to id the diode in the pic.
PQ30 has 19v on pins 5-8 rest of pins have 0v
PWR_SRC is 0v.
VH28 0v
Acok-2 0v

[momaka]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Thanks for the Help, upon closer inspection I found a couple of components blown down near the Sata connector. I was able to identify the Pq27 as a 1Mz2 I think , but I cant seem to id the diode in the pic.

Q27 could be a MOSFET, but I'm not entirely sure.
As for the overheated diode, it looks like it's the same as the one next to it. But that's not too much of a problem, since you can replace it with an axial though-hole one temporarily just to see if it works (when you replace the other bad parts, that is).

PQ30 has 19v on pins 5-8 rest of pins have 0v
PWR_SRC is 0v.
VH28 0v
Acok-2 0v

Not sure what these items are. Can't see them on the pic and I don't have this particular laptop in front of me so I can't tell you if those readings are right or wrong.

[scobie_21]

Re: HP DV6500 (dv66550ec) wont power on dc jack

Problem solved tahnks for the help.

Problem statement
-------------------
Laptop dead not powering up.
Used battery with small amount of charge and laptop boots fine.
Will not charge or power up from mains.

Solution
----------
Found Pq27 IMZ2 (Bipolar Small Signal NPN/PNP) damaged and short.
Found Diode (PD12 I think unable to see marking on CB) short.
Pq30 pins 1-3 )0V
VH28 =0v

Replaced both pq27 and diode and laptop powers up from adapter again.

Again thanks to all.