HP Envy 15 cannot charge battery!

[grahamw01]

Hi everyone,

I would much appreciate some help with my laptop!

I am having endless unfortunate problems with this laptop. First it just died and would not turn on what so ever, I got fed up of trying to repair it so just purchased a new motherboard from China. At first I assumed everything was fine again because it worked perfectly, although I did not have a battery, it was working fine off the charger.

I purchased a new battery for it from China and it arrived just a few days ago. Initially I still thought everything was fine because the battery arrived 80% and it seemed to work perfectly, then as the battery ran out I got the most frustrating problem of all, it would not charge.

When I put the AC adaptor in, it just cycles through charging and not charging every few seconds. I assumed the charger has gone, because I know this is a common problem with some laptops (it will run fine with the adaptor plugged in but will not charge the laptop)

But just before I wasted more money on a new charger I did a few tests. I still have the original motherboard, so I hooked up the AC adaptor and put the new battery in it, and it charged fine! Went back up to 100% within a few hours, and I was able to run the new motherboard off it again until it died.

So, I have narrowed it down to the NEW motherboard also being faulty! Would anyone happen to know how to fix it? I am sure it is possible to exchange some components related to charging from the old motherboard on to the new one, does anyone know what could be wrong?

I checked the voltage on the battery connector when the power cable is plugged in, on the one that wont charge it is constantly 19.5V, which is the full power of the adaptor and seems very wrong when the battery is only 11.1V.

The motherboard that will charge has -0.3V on the battery pins, until charging is activated and it goes up to 12V.

I apologise for this essay, but I would be so grateful if someone could help me. I want this laptop back!!

Many Thanks,
Graham

[heavymachines]

Re: HP Envy 15 cannot charge battery!

pull motherboard and do side by side test i would start at the 8 pin mosfets around the battery area and dc jack area...hp is known for massive issues their problems have not improved since the days of dv series....

[grahamw01]

Re: HP Envy 15 cannot charge battery!

thanks, yea I have tested most of the IC's and transistors around the adaptor and battery area, i replaced a few ICs and transistors with different resistance but nothing.. there has to be something!

[heavymachines]

Re: HP Envy 15 cannot charge battery!

thanks, yea I have tested most of the IC's and transistors around the adaptor and battery area, i replaced a few ICs and transistors with different resistance but nothing.. there has to be something!

make sure you use same type resistors and values if your start changing resistance that's gonna take a chance of messing something up more and make matters worse..

...you can use higher rated mosfet to an extent,, but has to be internally the same..another words you will need to find data sheets on the original mosfet and the donor mosfet to make sure it's compatible...



unless your using exact same parts directly for your other envy motherboard however we kinda wanna leave that one intact so we can do live test to see what is getting power for the charge system if we need to do so......



btw pictures are worth a thousand words on this forum. Please take clear focused pictures of both sides of motherboard... that will help everyone here to help you....

[grahamw01]

Re: HP Envy 15 cannot charge battery!

Hi again,

What I mean about replacing components is I am assuming as the motherboards have the same model number then the components are the same, therefore each component and its equal component on the other motherboard should have the same value of resistance when checking right?

So when I came across some transistors that had different values, I swapped them to see if it would make a difference, but it didn't.

I only have a picture of the top of the board as I left it all at work for now. I have good facilities to quickly swap components, I just hope it is 1 component that can be replaced and someone can help me identify it!

Please note the images attached are of the original motherboard, that has a working charging circuit but does not work in general.

Thanks

[nish_pinto]

Re: HP Envy 15 cannot charge battery!



Hello graham. I had repaired an envy 15 about 3-4 months ago. It has the same issue as you say. Sometimes it would charge and sometimes it wouldnt. It would boot with the charger plugged in and still not charge the battery.

So I went to the BIOS screen and hit 'default settings'. Still the same thing.

I tried reflowing some of the mosfets located near the battery charging pin. Still no luck. After trying various sorts of repair attempts I took a soldering tool and flux and re-soldered the pins (marked in the picture). To my surprise, it worked,

[heavymachines]

Re: HP Envy 15 cannot charge battery!

Hi again,

What I mean about replacing components is I am assuming as the motherboards have the same model number then the components are the same, therefore each component and its equal component on the other motherboard should have the same value of resistance when checking right?

So when I came across some transistors that had different values, I swapped them to see if it would make a difference, but it didn't.

I only have a picture of the top of the board as I left it all at work for now. I have good facilities to quickly swap components, I just hope it is 1 component that can be replaced and someone can help me identify it!

Please note the images attached are of the original motherboard, that has a working charging circuit but does not work in general.

Thanks

please circle what you changed .....

if you want us to help you identify parts we will need those part numbers on the ic in question....

if you swap parts they must be same values...

[heavymachines]

Re: HP Envy 15 cannot charge battery!

try what nish said before we go further....

[grahamw01]

Re: HP Envy 15 cannot charge battery!

Thanks for all your responses, I will try what nish has suggested. At first I believed it would be the pin in the adaptor cable that determines what the adaptor type is, I know if the motherboard in some laptops does not know the power output of the charger, it will only power the laptop but not charge the battery.

It would make sense then if there is a dry joint on the socket for this wire, so the motherboard is unable to determine what the adaptor is and will refuse to charge the battery. I chose to ignore this though when I discovered there is 19.5V on the battery connector when there should be nothing. This seems extremely wrong. The battery is only 11.1V, and I think when its charging it goes to a maximum of 12V on these pins, and that is only when the motherboard turns on battery charging.

The IC's I changed were the 2 8-pin ones located next to the battery socket, they can be seen in the picture. I believe these are not important, the original motherboard was able to charge the battery even with these removed.

I will try to resolder the connector tomorrow as kindly suggested by nish, but since there is 19.5V coming out of the battery connector I think there is a bigger problem.

Thanks

[heavymachines]

Re: HP Envy 15 cannot charge battery!

keep in mind when there is loss of connection somewhere it could send wrong voltages hence malfunction because it does not have the proper connection to determine what voltage it suppose to send.....so we have voltage regulation problem.... so in theory not saying that's what it is but in theory it not getting the charge pin info "voltage" by the adapter , so by default the regulator maxes out at full adapter voltage because it not being told otherwise....



so with that in mind i would reflow those solder joints and do a continuity test to make sure it's getting proper connection....

[heavymachines]

Re: HP Envy 15 cannot charge battery!

The IC's I changed were the 2 8-pin ones located next to the battery socket, they can be seen in the picture. I believe these are not important, the original motherboard was able to charge the battery even with these removed.



those just switch power from battery to adapter to adapter to battery but since that motherboard is dead you don't see any difference because the system does not power on to notice it's gone....these are for run switching... hence power run mosfets....what you want to watch out for is voltage regulator for some reason its max out on one board and being told 0 volts on the other...in theory...

[heavymachines]

Re: HP Envy 15 cannot charge battery!

i noticed you have the newer type voltage regulators supposed to be more power efficient and run cooler then the older type.. i don't know much about the newer style other then that stated above...call me old school i guess...but without schematics it's very hard to tell how exactly it supposed to work... so all i can offer is theory at this point...there are plenty of knowledgeable people that are on here that can help and more knowledgeable then myself...

[heavymachines]

Re: HP Envy 15 cannot charge battery!

on the motherboard that is dead you should be able to tell what is getting voltage and what is not do a live test and have steady hands use the motherboard ground for the negative reference point... and see what is live from the dc jack all the way to the battery then do the same of new motherboard and you should be able to tell where it's not getting voltage at while it's off of course ...trace it down....

[grahamw01]

Re: HP Envy 15 cannot charge battery!

Thanks a lot for all your help, I will have a play around with it tomorrow.

Regards

[grahamw01]

Re: HP Envy 15 cannot charge battery!

I just did a continuity test on all the adaptor pins and they seem fine, I have not had chance to re solder them yet but unless they have multiple connections internally I don't think it is the problem. Hopefully I can give it a go on my lunch.

Thanks

[nish_pinto]

Re: HP Envy 15 cannot charge battery!

And by the way, have you been able to locate an ISL ic on the other side of the board? And if time allows please post a picture of the other side of the board.

[grahamw01]

Re: HP Envy 15 cannot charge battery!

bottom of board attached, I don't have time to play with it at the moment (I should be working!)

thanks

[grahamw01]

Re: HP Envy 15 cannot charge battery!

I just resoldered the power connector and it did not fix it i did a continuity test on all pins and they are fine

[grahamw01]

Re: HP Envy 15 cannot charge battery!

really annoyingly, both motherboards are now doing exactly the same thing after putting the ICs back. 19.5V on the battery, constantly switching between charging and not charging now..

[grahamw01]

Re: HP Envy 15 cannot charge battery!

okay so I had another play around with the original motherboard after work, I swapped the 2 8-pin IC's around that I originally took off (the closest ones to the battery socket), and it started charging without a problem again (I must have just put swapped them over accidentally in the first place, doh!)

Anyway interestingly the motherboard developed the exact same fault I am trying to repair when these ICs were the wrong way round, is this just coincidence??