# Laptop only runs on battery, not AC?



## sgtrock (Sep 2, 2011)

Hi all,

I'm reposting this from a post I made in the official HP "no-support" forums. I hope someone here can help. Any advice is appreciated.

My wife has a HP G60 DX535 laptop. She is running Windows 7. A few nights ago Windows Update installed a bunch of updates. Since then she has been unable to charge it using her AC adapter. It will boot and run fine on the battery, but it will *not *run on the AC adapter *at all*. (not sure if this is a software issue at all, but it is an odd coincidence)

The AC adapter is 18.5V. I tested it briefly with a 19.5V Dell AC adapter and it charges! But it won't charge with the HP 18.5V adapter! I then assumed the adapter had coincidentally died at the same time. Yesterday I received a new HP 18.5V charger in the mail, identical to her current one, and it won't charge the laptop either! So now I'm REALLY confused. If it is a problem in the power port (??) then wouldn't it refuse to charge from ANY adapter? 


I confirmed the following:

1. It will not run on AC power at all using the HP 18.5V adapter.

2. It will run on AC power using the Dell 19.5V adapter.

3. It will not charge the battery (icon says running on battery only) when using the HP 18.5V adapter, but it WILL charge using the 19.5V Dell adapter.

I do NOT want to use the Dell adapter for fear of frying something inside the laptop. The laptop is almost two years old and therefore outside the HP warranty, but I believe we purchased a two year extended warranty from Best Buy when we bought it originally, though I currently can't find the paperwork... :upset:


I have tried the following:

1. Removed battery and re-seated it. She had a routine problem where the system would not boot sometimes and you had to re-seat the battery to get it to come on. This did not resolve the problem.

2. Read on another HP site to uninstall the Microsoft ACPI driver in the Batteries section in Device Manager, and re-scan for new hardware. Did that, no change.

3. I don't see anything in the BIOS regarding battery at all, so not sure about that angle. I've seen people refer to the BIOS but I can't see why.


I would run the HP Battery Tester but it is not available for download for the 535DX. I would buy another battery, but this one seems perfectly fine, although it has always run out within 1-2 hours, not the 3-4 it is supposed to last.

So my question is, what would cause the laptop to refuse to accept power from it's own adapter, but it WILL accept power from a stronger adapter?


I'm really stuck here. Any advice/guidance is much appreciated. *Thank you!*



Note: Since writing the above I have also tried another HP adapter, this one 19V. It works the same as the 19.5V, i.e. it charges the battery and boots the laptop when there is no battery in it.


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## GZ (Jan 31, 2010)

Hello sgtrock and welcome to TSF,

First glance would say there is an issue with your original HP adapter. Is the center pin of the adapter's plug intact?

As for the second HP adapter, you stated it boots the laptop... does it do this with the battery installed or not?


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## sgtrock (Sep 2, 2011)

Hi gavinzach,

Sorry for the late response, been at work all day. I'll double-check on the pin on the original adapter when I get home. To answer your specific question, I booted it both with and without the battery using both the Dell 19.5V and the HP 19.0V adapters. Neither of the HP 18.5V adapters will work.

Just to clarify, there are now four adapters at play in my description, I may not have been very clear:

1. The original HP adapter that came with the laptop, 18.5V. This one will no longer boot the system or charge the battery.

2. A second, identical HP adapter, 18.5V, purchased because I believed the original went bad. This one also will not boot the system or charge the battery.

3. A third adapter, Dell, 19.5V. This charger DOES boot the system, and DOES charge the battery.

4. A fourth adapter, HP, borrowed from work, 19.0V. Like the Dell, this charger also DOES boot the system and DOES charge the battery.

For #3 and #4, I don't want to use them for more than a couple of minutes for testing, because I'm worried about pushing too much current into the laptop and damaging the system somehow.

The thing that throws me is, why do the two 18.5V HP adapters (one of which is the original that came with the laptop, the other arrived in the mail a couple days ago) not charge or boot the system, but the more powerful ones (19V and 19.5V) do? I've read that the power port could be an issue, and I'm not very familiar with laptop-specific hardware (I used to build my own PCs in the early 2000s but not laptops), but it seems to me that if the power port is broken or "loose" then NO power would get through at all, regardless of the type of adapter used.

This is what has me stumped. Appreciate the help.


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## GZ (Jan 31, 2010)

There could be something causing resistance (i.e. bad solder joint on DC jack) that can cause a voltage drop sufficient enough to cause the computer to not operate from the standard operating voltage.

If something like this were occurring, heat would be produced which can damage the laptop and be a possible fire hazard.

Is the computer still under warranty?


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## sgtrock (Sep 2, 2011)

Wow, that sounds really bad.. 

No, it is almost two years old (Oct/Nov timeframe). My wife and I are pretty sure we bought an extended warranty (2 years) for it at Best Buy, and I swear I put together a folder for it when we bought it, but so far I can't find the paperwork... 

Her laptop has always run hot. In fact, her previous HP also ran very hot, so we just thought this was "an HP thing". My Dell never really ran hot until lately, and I have a new hard drive on the way that should fix that problem for me. So I just thought it was the way HP designs their systems.

The battery on her laptop also has never lasted the 3-4 hours it supposedly should. It always runs out in 1 hour, 2 hours maximum. Don't know if that is relevant or not.

So is there nothing else I can really check myself, just take it into BB or another shop?

Thanks.


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## GZ (Jan 31, 2010)

The heat from a resistance short will be very localized. You may not feel it on the outside of the case, but you may be able to feel it on the adapters DC plug when first removed from the system. 

Are you comfortable disassembling your computer to do a little investigative work?

I can't find the service manual on the HP website, but this looks right...

Hp g60 Presario Cq60 Service Manual


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## sgtrock (Sep 2, 2011)

Yes actually that looks right. I am not averse to taking the back off and looking around, but looking through that manual I don't see anything specific to the DC jack. I do see some other sites and even a video discussing it though, so I'll take a look at them and see what I can figure out. I'm not going to try any repairs myself though, no soldering kit or experience, but maybe I can at least see something wrong.

Is there anything specific I should look for?

I'll be out of town today but if you can think of something I should look for I'll take that with the instructions and videos and see what I can see tonight or tomorrow morning.

Thanks.


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## sgtrock (Sep 2, 2011)

I just went and checked (without opening the laptop, using a pencil) and the port definitely moves a good bit. I plugged the original 18.5V charger in and wiggled it but it never lit up.

I called a couple repair folks here in town and one quoted me $75 flat rate for a few hours turnaround, but he mentioned possible motherboard damage. He also said if the 19V worked the 18.5V should work, which is why he mentioned the motherboard.

I'm going to call Best Buy as well and see what our options are. From what I can read online though it doesn't look like they will do any soldering work at all, so we may have to get the laptop repaired locally. I can pay the $75 no problem, but my wife is wary of the idea of someone poking around like that. I'm wary of taking it to some guy's house for repair but that seems to be the only option in this town, vs sending it off for 1-2 weeks to a service I can find online.

One more question: When you mentioned heat damage is that the same as what the guy was trying to tell me? He didn't get specific, he just said "it could damage the motherboard and it can only be repaired so much". I understand that, just want to be sure I fully understand the whole picture before going down that road.

Thanks for all the help, you gave me more to go on so I could have a more intelligent conversation with the repair shops. That's way more than HP "support" ever did.


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## GZ (Jan 31, 2010)

Heat damage from a resistance short could cause weakened and burnt traces as well as PCB separation.

In your computer the power jack is not soldered to the board, so it will have some play in it.

Do you have a multimeter or voltmeter?

Take the computer apart and remove the DC Jack.
Plug the power adapter into the DC Jack.
Use the voltmeter or multimeter to check the voltage at the opposite end using the probes.


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