laptop pavilion dv7900 wont start but i get blue lights

[Munro_be]

i have a pavilion dv7900 running vista.

i came back from holiday, turned the machine on a nothing. the blue light at the mains power inlet is on and when i push the power button the row of blue lights on the top menu bar below the screen light up momentarily and then go out.

what to do?

[Siby_M]

Hi Munro_be,

I am sorry to hear about this issue.

First, please perform a Hard Reset as the following document says. If that does not resolve your issue, please check the section that says “Symptom: LED lights do not glow, display is black, computer does not start” in the following document and perform all the steps that might help us in fixing this issue.

Overview of Troubleshooting Startup Problems (Windows 7, Vista, XP): http://support.hp.com/us-en/document/c01443371

I am waiting to hear back from you.

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I am an HP Employee.

[Munro_be]

Hello and thank you for getting back to me

I've been through the tests and documents but without a successful outcome.  And in my opinion, the description of the fault also does not fit exactly with the document sections.  Can I explain?

Firstly when I plug the mains lead into the computer, the light around the connection point on the laptop lights up blue as does the blue light at the front of the computer indicating that it's on mains power. 

Secondly, when I press the power button on the computer I get no bleeps or sounds.  What happens is that the blue lights on the quick play menue bar light up for approx 1 second before going out.

And that's it.

Does this suggest any particular fault to you or the need for any further tests?

Kind regards

Bruce

[Siby_M]

Hello Bruce,

I understood the symptoms that you had explained completely.  I am sorry for referring you to the wrong section. 

Let me explain.

Since you are able to see the LED light on the Adapter port glowing and the blue LED on front of the Notebook to be glowing, it means that the Adapter is working fine and so is the Adapter port. Your Notebook is getting charged from outside but is not able to turn ON properly. I understand that you are seeing the Shorcut LED buttons (Quick Launch keys) coming up for a second and then going off. This issue could be with the power connection inside the Motherboard. But we cannot be sure yet. 

I am curious to know whether you have already done the Hard Reset step that I suggested. If not, please go ahead and try that first.

Performing a hard reset

Disconnect all peripheral devices and remove all USB devices and SD media cards.

Disconnect the AC power adapter, remove the battery and then press and hold the power button for at least 15 seconds to drain all residual power and restore default startup settings.

Reconnect the AC power adapter (but do not insert the battery), press the Power button, look for glowing Light Emitting Diodes (LEDs) near the caps lock and num lock keys, and listen for sounds of a fan or other moving parts turning.

If the computer starts normally after performing a hard reset, you are done troubleshooting.

If the above step does not make any difference, we will go ahead and reseat the Memory (RAM) and the Hard Drive (HDD) on the Notebook and see whether that makes a difference.

Reseating RAM:

First we will have to try reseating the RAM.  Your Notebook should have 2 RAM slots. If you have got a single RAM Module, you can try removing that from the existing slot and place it on the other one and see whether the Notebook turns ON after that. If you have got two Modules, you can try swapping  them. If that too does not work, try turning ON the Notebook with only 1 Module inserted and also by changing the slot. You will have to work the permutations and see whether the Notebook turns ON. This is to understand whether the issue is with any of the RAM slots or the RAM module itself.

Please find details on how to reseat and insert back the RAM from the following document:

General document on Steps for Removing and Replacing Memory Modules: http://support.hp.com/us-en/document/c00262554

Reseating HDD

We will reseat the Hard Drive cables and will put it back to its actual position.

General document on Steps for Removing and Replacing the Hard Disk Drive: http://support.hp.com/us-en/document/c00649950

You just have to reseat the Hard Drive cable and then insert it back to its actual position. This is to ensure there is no loose connection or static electricity accumulation. Check whether the Notebook works properly after doing this. 

I am waiting to hear back from you.

!------------------- Please click the KUDOS star on the left to say 'Thanks'.

Please mark 'Accept as Solution' if it solves your problem. Thank you-----------------------------------------------------------------!

I am an HP Employee. 

[Munro_be]

Hello and thank you again for the response.

I did try these tests a week or so ago but have now repeated them and again without a positive outcome.

Any further thoughts would be appreciated.

Kind regards

Bruce {Personal Information Removed}

[Siby_M]

Hi Bruce,

You are very welcome. 

Oh, I see. I am sorry to hear that.

If you had tried all the steps above without any positive result, it means that there is something wrong with the Motherboard on the Notebook which is definitely a hardware failure.  In this case you will have to contact HP to get the Notebook repaired.

Please contact HP over the Phone/E-mail/Chat. If you are in the USA/Canada, please contact HP over the Phone at 1800-474-6836.

HP US Support: http://h10025.www1.hp.com/ewfrf/wc/siteHome?cc=uk&lc=en

HP Worldwide Support: http://www8.hp.com/us/en/contact-hp/ww-contact-us.html

Please find more details for contacting HP from the link below:

http://www8.hp.com/us/en/contact-hp/contact.html

!------------------- Please click the KUDOS star on the left to say 'Thanks'.

Please mark 'Accept as Solution' if it solves your problem. Thank you-----------------------------------------------------------------!

I am an HP Employee.