[Richard Long]

I have an HP pavillion laptop about 2 years old.
When I plug in the power supply after about 30 seconds I get a high pitch whistle from the laptop.
This happens with the laptop on or off.
If I remove the battery the whistle disappears.
Does anyone know what this is and is it putting my laptop at risk.

[whoever,hey]

Could be a build up of dust in the case.

The extra heat from the battery may be just speeding up a fan (which is fine) to cool it back down.

[Richard Long]

Originally Posted by whoever,hey

Could be a build up of dust in the case.

The extra heat from the battery may be just speeding up a fan (which is fine) to cool it back down.

Thanks for your reply but this happens when the machine is switched off and the fan is not operating.
The sound seems to be comming from the battery area.

[flagpole]

Originally Posted by Richard Long

Thanks for your reply but this happens when the machine is switched off and the fan is not operating.
The sound seems to be comming from the battery area.

what whoever,hey is suggesting is that the battery charging may generate enough heat to require a fan and that this could happen even when it's switched off.

if it's not a fan noise and the battery itself is making the noise i should contact the manufacturer.

[Richard Long]

I appreciate everyone's help here but it is not the fan.
It sounds like a whistling kettle in another room
Does anyone else have any idea.

[Stig]

Originally Posted by Richard Long

I appreciate everyone's help here but it is not the fan.
It sounds like a whistling kettle in another room
Does anyone else have any idea.

It's the battery charging. Remove it and see what happens.

You are cursed with ears that are too sensitive, like me!

[Richard Long]

Originally Posted by Stig

It's the battery charging. Remove it and see what happens.

You are cursed with ears that are too sensitive, like me!

LOL!
It stops if I take the battery out.
I was just wondering if this is a problem of something failing that may damage the laptop when it dies.

[Stig]

Originally Posted by Richard Long

LOL!
It stops if I take the battery out.
I was just wondering if this is a problem of something failing that may damage the laptop when it dies.

I don't think it's a major problem. It's just cheap and nasty components inside the battery charging mechanism that squeal.

A new battery might solve it, but who knows...

[Bungitin]

Try and find someone with the same sort of battery before committing yourself to a new one. They are a bit expensive to try to solve by buying a substitution and finding it still does it.

[Richard Long]

I managed to swap the battery with another machine.
The noise was not as bad with what is a fairly new battery but it was still there.
There was no noise when I put the battery from the troublesome machine in another laptop.
Bottom line is it looks like it is something to do with the charging cicuit in the laptop itself.
Think I need to vivit a computer repair man to get it checked.

Many thanks to all for all the help.

[LION8TIGER]

How about trying a different adapter/charger, that would be everything ruled out then apart from the laptop itself.

[ilovekrys]

hi have a look on the hp website and type in battery recall, and type in your battery number and then it will tell you if you have a battery which has been recalled. if not it sounds like your battery is on its way out

[caboose]

Could be the switch mode power supply/charging circuit in the laptop, sometimes they will resonate and make a high pitch noise. I had a mac which did the same and i replaced the power supply capacitors which solved it.

[Richard Long]

Tried a new charger as that was doing the same thing but louder.
No sign of recall for my model on the HP website.

Someone else suggested capacitors so I think I will get them looked at.