LaptopDisplay

Disclaimer:

All comments posted to this web site are opinions expressed by the poster and/or the owner of this web site. The owner is not responsible for comments or repairs to computers that others may do. I will warn you that you may be violating your computer manufacture's warrantee for certain things. Be sure to read it before opening your computer case!

I work hard to expand this free information.

You may express your gratitude by donating with your help supporting the server costs and help keeping the section alive.

LaptopDisplay

by Johh
(Plantsville,ct. USA)

Have a 3 year old Toshiba laptop.

Model P105 S9337.

For the past 2 months it has been going thru a strange cycle.

Perhaps I should not use the term cycle for there seems to be no rythum.

One day it came on, booted normally except there was no display. For a week it did this. (I am able to shut-down normaly using the keyboard.)

Then one day it came on and the display worked as it should. Everything ran as it should. The machine seemed to be ok.

For a week it worked normally. Then it repeated the senario. Came and booted but no display.

Have had the unit apart looking for loose connectors and\or defective looking parts. Found nothing.

The pc has gone thru 4 of these 'cycles'. Tried AC only and battery only without success. Wait 24 hours and 48 hours between tries, still nothing.

Been able to locate most of the parts for this machine but don't know the source of the problem so don't know what to buy.

Comments for
LaptopDisplay

Average Rating

Click here to add your own comments

Jan 24, 2011
Rating

Laptop dispaly intemittent.
by: Support

Hello John,

Your laptop display problem is the inverter. Sometimes you can use a can of compressed air to cool it down and it may come on.

The inverter is the weak point in a laptop display and is normally either beside the display or under it.

Those that the inverter is on the side of the display have lower failure rate, those behind the display fail more often.

The main reason for the failure is heat, if you can get it to come on after about five to ten minutes you can move your hand around the case side of the display you will find a 'hot spot' that is the inverter.

Now the question is can you find a replacement for the inverter?

Hope this helps ...

Jan 31, 2011
Rating

No display
by: John Hahl

Just received the new inverter for the Toshiba P105 S9337. Replacing the old one made no difference. Still no display.
Keeping in mind that new pc's are less expensive than they were 4 years age, what do you suggest I try next?

Jan 31, 2011
Rating

Laptop inverter is good ...
by: Support

Hello John,

If the inverter is good, what else came with the inverter?

Did you grt a new ribbon cable also?

Try this:

If you have access to a monitor connect it to the external VGA port, with the display open power up the laptop.

On the keyboard (normally in conjuction with the number keys) are some extra markings. There should be some either blue or white icons, you are looking for the one that looks like a monitor. Some laptops use one key some use two keys. This key stroke will change the display from internal, to external, or both: Fn key + the monitor key

Do you have:
Display on the external monitor?
Display on the Laptop?
Display on both?

No display at all?

Try using the Fn key + monitor key to cycle through the differnt settings for the display.

Do you get anything on either internal or external displays?

Yes, external, then the motherboard is good, no motherboard embedded video chip set has failed.

Yes, the internal is now working, then it was the inverter.

Hope this helps ...

Feb 03, 2011
Rating

Toshiba P105
by: John Hahl

Haven't yet tried another display but did take some voltage readings at the inverter. found 14 volts at the input end of the board but no voltage at the output end. No ac being applied to the backlight.
Without knowing for sure what is normal, it looks to me like the signal to turn the light on is not being generated from the video system.
The video section of this unit is a seperate, assembly connected to the motherboard via miltipul connectors and screws.
Have had no luck in finding the video board anywhere. What do you think?

Feb 10, 2011
Rating

Toshiba P105 S9337, Inverter
by: John Hahl

Left another reply on the 3rd in answer to your question. I repeate; Measured voltage at the inverter board.

Saw 14+ volts at the input end and got nothing at the connector to the backlight.

I suggest that the signal to turn the light on is not being generated by the system.

Do you know the source of this signal? The motherboard or the video board?

The video board is a piggybacked board attached to the mother.

This particular inverter has no ribbon cable connection from the system. Looks like a hand wrapped cable.

Feb 10, 2011
Rating

Toshiba Laptop Dispaly
by: Support

Hello John,

No, I don't know the source for the +14 volts.

If you are getting a signal from the piggy back card on the motherboard to the inverter and to the the display either the voltage is too high or the display itself has also failed.

With out the schematatics to see the out put from the video card and the output from the inverter are I am guessing at the cause.

Have you tried an external monitor on the VGA port to see if the video chipset is working?

Feb 15, 2011
Rating

update
by: John Hahl

Had time to test other video outlets on this unit. Assuming that the key functions are working, there is no signal to any other video types. No vga, no svideo. Looks like the video system is faulty.
Although the video board is a separate unit, the output connectors are located on the motherboard. Can we be sure the problem lies in the video board?

Feb 15, 2011
Rating

No video out from laptop to monitor
by: Support

Hello Johh,

The only way to test a video card (with out a oscilloscope) is to plug it in to another computer.

If you can't find another video card to replace the one you have the chances of finding another laptop with the same video card is just as slim.

Have you checked eBay for the same make/model of laptop to see if anyone has one they are selling for parts?

If it isn't the video card then the motherboard may have failed.

Do you know who made the video card? ATI and NVIDA were making them for Compaq and HP before they went to chip sets on the motherboard.

Hope this helps ...

Feb 16, 2011
Rating

Toshiba P105
by: J Hahl

It so happens I am watching another unit on ebay. It displays a blue screen but otherwise doesn't work. But, since it does have a working display I may be able to make one working unit out of the 2. I will let you know what happens. J.

Feb 23, 2011
Rating

Toshiba P105 Laptop
by: J Hahl

Well, I lost the bidding for the unit on ebay by $2.50. Found a video card for the defective init but the vender wanted $263.00. That's half of the cost of a whole new pc.
With that in mind, I will look for a replacement. The defective one will get fixed one day when the cost of parts comes down.
I will ok another month membership. Thanks for your time. I will be back I'm sure.

J. Hahl

Mar 10, 2011
Rating

Tosniba P105 laptop,no dispaly
by: John Hahl

Have given up, for the time being, on trying to
fix this machine. Unfortunatly you had the same luck I did with coming up with a firm fix. Perhaps this one will be more difficult than we expected. However, at some point in the future I will give it another shot. At that time I may return for more input. Mean time, if you should come across a solution, please send a mail.
Thank you for your time and input.
Regards, John.

Click here to add your own comments

Join in and write your own page! It's easy to do. How?
Simply click here to return to Q and A

Return to top

From the Desert South West ~ Arizona, USA

My Twitter!

Fire that geek that is messing up your computer, you can do a better job.
Finally geek secrets revealed then translated in to everyday English!

Self Computer Repair Unleashed! E-book

The Official www.diy-computer-repair.com Reference manuals

Get yours Today!

Home

E-Courses!

DIY Computer Repair Five Part E-Course

A seven part Advanced E-Course on computer repair for you!

Would you like to Over Clock your cpu and/or memory with out destroying them? Here is an E-Course that will show you how to do it!

What do you think of when you hear virtual computing?

Fix It! Your
DIY Computer Repair
Newsletter!
Click here to get your copy of Fix It!

Windows 7
is coming to a
computer near you!
Don't be left
wondering
what to do!

On Release day the free e-book will not be available and the price may go up!

Order your
copy of
Windows 7
Ultimate
Guide now!

My Twitter!

Please donate $5

LaptopDisplay

Comments for LaptopDisplay

Comments for
LaptopDisplay