Potential Toshiba Backlight Problem

Scott20 · 06-06-2008, 03:29 PM

Hello,
Well I'm currently having an issue with my laptop most likely to do with the backlight. What has happened is I was visiting my father and he decided to borrow my charger for his toshiba laptop. Well is charged sure enough but when I came back to find he had used it the charger wasn't in the best of conditions. Anyway I had to continue using it until a replacement would arrive, meanwhile the USB ports would have a light flow of electricity running through them (lovely and safe eh?)
Anyway now to the screen issue. I turned my laptop on the other day to find that the backlights came on for around 4 seconds then shut off. I let windows load and after playing around with switching the screen on and off (by changing the video card output between an external monitor and the laptop screen) I managed to get the backlights to stay on. Though there was now a slight buzzing noise that got louder the more the brightness was turned down. Also there is a slight flicker in the screen that lessens the more the brightness is turned down.Now most times I turn the screen on the backlight doesn't work unless I flick the screen on and off a few times. Today however it simply refused to turn on at all. I mean I can flick through and make the backlights turn on for a few seconds but they are at full brightness and then simply turn themselves back off again.
So what I really need to know is what the problem most likely is. Is it the backlights or is it something else? Thanks in advance for your time and effort.

**TriggerFinger** · 06-06-2008, 09:40 PM

hi,

it could be the inverter or the backlight. if you hear a buzzing sound when the backlight is ON, then it could be the inverter.

Scott20 · 06-06-2008, 10:52 PM

Actually yes there is a buzzing noise. Since I wrote the post the backlight refuses to turn on now at all. But anyway, there was a loud buzzing noise. So now that I have a good idea of the problem I will look around for an inverter. If anyone has any knowledge of them I would appreciate some info. I have repaired many desktops in my time (worked as a repair tech when I was staying in the USA for a few years) but this will be my first time working on a laptop.

**TriggerFinger** · 06-06-2008, 10:58 PM

do you still hear the buzzing sound? does it come from the LCD / the top lid? i ask because you could be hearing the fan.

Scott20 · 06-07-2008, 01:08 PM

Ah that made me laugh a bit to read that, thanks for the concern but it is coming from the LCD (well just at the very base of it) It's not the type of buzzing noise a fan ever makes it's more high pitched, not really sure how to explain it. Also the sound is never made when the backlights are off. I had my suspicions it was the inverter before I posted on here I just needed a second opinion. If at all possible I could do with some more info on inverters from anyone who has replaced one before. Thanks again for anyone who can give some info of this.

**TriggerFinger** · 06-07-2008, 01:42 PM

it's better to be sure.

an inverter looks like this .

easy to replace. best if you have a service manual to guide you in the removal and replacement procedure.

Scott20 · 06-07-2008, 06:39 PM

I was just looking for a service manual earlier. Thanks for the pic though that will help a lot. Heh can't wait until I can see my screen again! Is annoying having a desk lamp aimed at the screen =p

**TriggerFinger** · 06-07-2008, 07:51 PM

good luck then. let's hope your backlight is still good as this one is a pain to replace, well at least for me.

06-06-2008, 03:29 PM	#1 (permalink)
Scott20 Registered User Join Date: May 2008 Posts: 6 OS: windows xp pro sp2	Potential Toshiba Backlight Problem Hello, Well I'm currently having an issue with my laptop most likely to do with the backlight. What has happened is I was visiting my father and he decided to borrow my charger for his toshiba laptop. Well is charged sure enough but when I came back to find he had used it the charger wasn't in the best of conditions. Anyway I had to continue using it until a replacement would arrive, meanwhile the USB ports would have a light flow of electricity running through them (lovely and safe eh?) Anyway now to the screen issue. I turned my laptop on the other day to find that the backlights came on for around 4 seconds then shut off. I let windows load and after playing around with switching the screen on and off (by changing the video card output between an external monitor and the laptop screen) I managed to get the backlights to stay on. Though there was now a slight buzzing noise that got louder the more the brightness was turned down. Also there is a slight flicker in the screen that lessens the more the brightness is turned down.Now most times I turn the screen on the backlight doesn't work unless I flick the screen on and off a few times. Today however it simply refused to turn on at all. I mean I can flick through and make the backlights turn on for a few seconds but they are at full brightness and then simply turn themselves back off again. So what I really need to know is what the problem most likely is. Is it the backlights or is it something else? Thanks in advance for your time and effort.

06-06-2008, 09:40 PM	#2 (permalink)
TriggerFinger Moderator Hardware Team Join Date: Jan 2008 Location: LV, NV, USA Posts: 5,355 OS: DOS 6.0	Re: Potential Toshiba Backlight Problem hi, it could be the inverter or the backlight. if you hear a buzzing sound when the backlight is ON, then it could be the inverter. __________________ DBAN - Memtest86+ - BartPE - Linux LiveCD - ImgBurn - HDD Diags - Everest Mark the THREAD as SOLVED

06-06-2008, 10:52 PM	#3 (permalink)
Scott20 Registered User Join Date: May 2008 Posts: 6 OS: windows xp pro sp2	Re: Potential Toshiba Backlight Problem Actually yes there is a buzzing noise. Since I wrote the post the backlight refuses to turn on now at all. But anyway, there was a loud buzzing noise. So now that I have a good idea of the problem I will look around for an inverter. If anyone has any knowledge of them I would appreciate some info. I have repaired many desktops in my time (worked as a repair tech when I was staying in the USA for a few years) but this will be my first time working on a laptop.

06-06-2008, 10:58 PM	#4 (permalink)
TriggerFinger Moderator Hardware Team Join Date: Jan 2008 Location: LV, NV, USA Posts: 5,355 OS: DOS 6.0	Re: Potential Toshiba Backlight Problem do you still hear the buzzing sound? does it come from the LCD / the top lid? i ask because you could be hearing the fan. __________________ DBAN - Memtest86+ - BartPE - Linux LiveCD - ImgBurn - HDD Diags - Everest Mark the THREAD as SOLVED

06-07-2008, 01:08 PM	#5 (permalink)
Scott20 Registered User Join Date: May 2008 Posts: 6 OS: windows xp pro sp2	Re: Potential Toshiba Backlight Problem Ah that made me laugh a bit to read that, thanks for the concern but it is coming from the LCD (well just at the very base of it) It's not the type of buzzing noise a fan ever makes it's more high pitched, not really sure how to explain it. Also the sound is never made when the backlights are off. I had my suspicions it was the inverter before I posted on here I just needed a second opinion. If at all possible I could do with some more info on inverters from anyone who has replaced one before. Thanks again for anyone who can give some info of this.

06-07-2008, 01:42 PM	#6 (permalink)
TriggerFinger Moderator Hardware Team Join Date: Jan 2008 Location: LV, NV, USA Posts: 5,355 OS: DOS 6.0	Re: Potential Toshiba Backlight Problem it's better to be sure. an inverter looks like this . easy to replace. best if you have a service manual to guide you in the removal and replacement procedure. __________________ DBAN - Memtest86+ - BartPE - Linux LiveCD - ImgBurn - HDD Diags - Everest Mark the THREAD as SOLVED

06-07-2008, 06:39 PM	#7 (permalink)
Scott20 Registered User Join Date: May 2008 Posts: 6 OS: windows xp pro sp2	Re: Potential Toshiba Backlight Problem I was just looking for a service manual earlier. Thanks for the pic though that will help a lot. Heh can't wait until I can see my screen again! Is annoying having a desk lamp aimed at the screen =p

06-07-2008, 07:51 PM	#8 (permalink)
TriggerFinger Moderator Hardware Team Join Date: Jan 2008 Location: LV, NV, USA Posts: 5,355 OS: DOS 6.0	Re: Potential Toshiba Backlight Problem good luck then. let's hope your backlight is still good as this one is a pain to replace, well at least for me. __________________ DBAN - Memtest86+ - BartPE - Linux LiveCD - ImgBurn - HDD Diags - Everest Mark the THREAD as SOLVED