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From: nick on 8 Jan 2010 13:13
I've been given one of these that is dead.

When you press the power button the power light flashes green once and
that's it. No fans, no disk, no screen, nothing.

With a charger plugged in the battery light shows green i.e. it
thinks the battery is fully charged.

Checked the battery with a meter and it looks good.

I guess it's either a power supply fault or something dragging one of
the power rails down.

I'd like to get it going, but although I've built and repaired lots
of desktops I lack experience with laptops.

Any advice would be welcome.

From: BillW50 on 8 Jan 2010 13:38
In news:hi7sjl$sh3$1(a)news.eternal-september.org,
nick typed on Fri, 8 Jan 2010 18:13:17 +0000 (UTC):
> I've been given one of these that is dead.
>
> When you press the power button the power light flashes green once and
> that's it. No fans, no disk, no screen, nothing.
>
> With a charger plugged in the battery light shows green i.e. it
> thinks the battery is fully charged.
>
> Checked the battery with a meter and it looks good.
>
> I guess it's either a power supply fault or something dragging one of
> the power rails down.
>
> I'd like to get it going, but although I've built and repaired lots
> of desktops I lack experience with laptops.
>
> Any advice would be welcome.

Hi Nick! It is the same as a desktop. Start pulling devices out, like
the hard drive, optical drive, memory, WiFi, etc. With any luck, it will
be one of them.

Say does it act the same running from the battery alone? Did you also
try running it on AC with the battery removed?

Is there a reset hole anywhere? Careful, if it has a built-in mic, don't
use a paperclip in the mic hole. As you would puncher the mic. And
pressing the reset is usually done without AC and the battery. Press on
hold and also press and hole the power button for 30 seconds or so. Then
give it a shot.

If all of this fails... it is either the AC adapter or the motherboard
most likely.

--
Bill
Gateway M465e ('06 era) - Windows XP SP3


From: nick on 10 Jan 2010 16:32
Hi Bill, thanks for your useful reply. Please see update below.

BillW50 wrote:
> Hi Nick! It is the same as a desktop. Start pulling devices out, like
> the hard drive, optical drive, memory, WiFi, etc. With any luck, it will
> be one of them.
>
Well it turned out that the hard disk was U/S, but I think there's a
charging problem.

> Say does it act the same running from the battery alone? Did you also
> try running it on AC with the battery removed?
Yes. It won't run on AC with the battery removed, perhaps because I
don't have the right adapter. Tried to run it from a bench supply good
for 15V at 4A, or 19V at 1A.

> Is there a reset hole anywhere?
Can't find any reset. The only reset mentioned in the manual is the one
for the BIOS settings.

> If all of this fails... it is either the AC adapter or the motherboard
> most likely.
Agree. Before I invest in a proper adapter here's what I did today.

Since the battery wouldn't charge in situ charged the battery
externally from the bench supply; about 1A for 3 hours. Refitted the
battery and the machine went through POST and then tried to boot;
that's how I found the hard disk was U/S.

Rebooted from an Ubuntu CD and everything worked. Plugged in the bench
supply and the machine was drawing about 3.5A, but none of it was going
into the battery. The charge LED was off, so I think the bench supply
was doing most of the work and the battery was making up the difference.
It ran over 5 hours like this.

Shut down the machine, but the charge LED stayed off. Ran the battery
right down, then plugged in the bench supply. The charge LED then comes
on after 10 seconds or so, but the current drawn is <100mA so it will
never charge. How can the laptop know about the type of charger, other
than by sensing the voltage?

Bottom line is that the battery appears to be in reasonable shape, but I
can't charge it in the laptop. When the machine is on it won't
charge from the bench supply, perhaps because it all needs more than 4A.
When the machine is off ditto because there's only a tiny amount of
current being drawn from the supply, probably none of it going to the
battery.

Do you think an adapter with the right ratings will help, or that
there's something wrong with the charging circuit inside?

Nick

From: BillW50 on 10 Jan 2010 17:53
In news:hidh18$655$1(a)news.eternal-september.org,
nick typed on Sun, 10 Jan 2010 21:32:33 +0000 (UTC):
> Hi Bill, thanks for your useful reply. Please see update below.
>
> BillW50 wrote:
>> Hi Nick! It is the same as a desktop. Start pulling devices out, like
>> the hard drive, optical drive, memory, WiFi, etc. With any luck, it
>> will be one of them.
>>
> Well it turned out that the hard disk was U/S, but I think there's a
> charging problem.
>
>> Say does it act the same running from the battery alone? Did you also
>> try running it on AC with the battery removed?
>
> Yes. It won't run on AC with the battery removed, perhaps because I
> don't have the right adapter. Tried to run it from a bench supply
> good for 15V at 4A, or 19V at 1A.
>
>> Is there a reset hole anywhere?
>
> Can't find any reset. The only reset mentioned in the manual is the
> one for the BIOS settings.
>
>> If all of this fails... it is either the AC adapter or the
>> motherboard most likely.
>
> Agree. Before I invest in a proper adapter here's what I did today.
>
> Since the battery wouldn't charge in situ charged the battery
> externally from the bench supply; about 1A for 3 hours. Refitted the
> battery and the machine went through POST and then tried to boot;
> that's how I found the hard disk was U/S.
>
> Rebooted from an Ubuntu CD and everything worked. Plugged in the
> bench supply and the machine was drawing about 3.5A, but none of it
> was going into the battery. The charge LED was off, so I think the
> bench supply was doing most of the work and the battery was making up
> the difference. It ran over 5 hours like this.
>
> Shut down the machine, but the charge LED stayed off. Ran the battery
> right down, then plugged in the bench supply. The charge LED then
> comes on after 10 seconds or so, but the current drawn is <100mA so
> it will never charge. How can the laptop know about the type of
> charger, other than by sensing the voltage?
>
> Bottom line is that the battery appears to be in reasonable shape,
> but I can't charge it in the laptop. When the machine is on it won't
> charge from the bench supply, perhaps because it all needs more than
> 4A. When the machine is off ditto because there's only a tiny amount
> of current being drawn from the supply, probably none of it going to
> the battery.
>
> Do you think an adapter with the right ratings will help, or that
> there's something wrong with the charging circuit inside?

Hi Nick! Laptops if the supply voltage is too low or if it figures out
that the supply just doesn't have enough current. They will often refuse
to charge the battery, but work fine otherwise. So that could be what is
going on here. Charging the battery is often half of the total draw
while the laptop is on.

Why the charge light only comes on for about 10 seconds and a draw of
100ma is interesting. It could be the laptop is unhappy about the
voltage and waits 10 seconds before giving up. Although it could decide
something is wrong with the battery too. So I would keep this in mind as
well.

Otherwise you are on the right track. I am assuming the 3.5 amp draw was
at 15v, eh? I don't know what the original one put out, but 19v at 3.5
amps is very common. My docking station has a supply of 19v at 6.3 amps.
Overkill for what I use it for. Although it supports much beefier
laptops than mine.

And you say you are charging the battery on the bench. Have you charged
lithiums before? As if you overcharge them or charge them too fast, they
will explode. It is usually recommended if you charge them without
safety circuits, to place them in some sort of metal container. Thus if
it does burst into flames, it shouldn't catch anything else on fire.
Plus don't throw water on it if it does. As I believe that only makes it
worse.

--
Bill
Gateway M465e ('06 era) - Windows XP SP3


From: nick on 11 Jan 2010 06:15
BillW50 wrote:

Hi Bill,

thank you for another great post.

today I am lashing up a 19V supply from 3 desktop supplies to see what
gives. Anyway please see comments below.

Nick

PS: Is your email attached to this post good? If so I'll take this
thread off the group, if that's OK with you.

>> Do you think an adapter with the right ratings will help, or that
>> there's something wrong with the charging circuit inside?
>
> Hi Nick! Laptops if the supply voltage is too low or if it figures out
> that the supply just doesn't have enough current. They will often refuse
> to charge the battery, but work fine otherwise. So that could be what is
> going on here. Charging the battery is often half of the total draw
> while the laptop is on.
The adapter rating for this laptop is 19V at 4.74A i.e. 90W.
Presumably the adapter would be capable of running the laptop
and charging a completely discharged battery. So the current
split is probably 2.5A for the laptop, and 2A for the battery. It's a
4Ah battery so the initial charge current would be C/2 which makes
sense.

>
> Why the charge light only comes on for about 10 seconds and a draw of
> 100ma is interesting. It could be the laptop is unhappy about the
> voltage and waits 10 seconds before giving up. Although it could decide
> something is wrong with the battery too. So I would keep this in mind as
> well.
Not quite. When you plug in the adapter the charge light is initially
off. After about 10-12 seconds it come on (amber) and stays on for as
long as the adapter is plugged in.

>
> Otherwise you are on the right track. I am assuming the 3.5 amp draw was
> at 15v, eh? I don't know what the original one put out, but 19v at 3.5
> amps is very common. My docking station has a supply of 19v at 6.3 amps.
> Overkill for what I use it for. Although it supports much beefier
> laptops than mine.
>
Yes 3.5A at 15V. Been looking at adapters on ebay. Thought I might
invest in a 19V 6.3A one so there's a bit of spare capacity.

> And you say you are charging the battery on the bench. Have you charged
> lithiums before? As if you overcharge them or charge them too fast, they
> will explode. It is usually recommended if you charge them without
> safety circuits, to place them in some sort of metal container. Thus if
> it does burst into flames, it shouldn't catch anything else on fire.
> Plus don't throw water on it if it does. As I believe that only makes it
> worse.
>
Yes I have done this before. Thanks for the warnings though.

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