Possible Inverter Issue?

T60/T61 series specific matters only
Post Reply
Message
Author
taichi
Senior Member
Senior Member
Posts: 574
Joined: Mon Oct 29, 2007 2:07 pm
Location: Los Angeles, CA

Possible Inverter Issue?

#1 Post by taichi » Tue Mar 31, 2015 11:23 am

A few months ago, on my T60P, when I went away from my computer and came back I noticed that the screen had gone dark. The computer was still running. I then resorted to restarting the computer and display was fine. I thought perhaps that this was some setting issue with the power management, or possibly a screensaver, although I have everything set to leave the display on at all times.

Then these instances of the screen going dark became more frequent, and then I discovered that by closing the lid and opening again the screen would come back to life. However, the instances of darkening now have increased to the point that the screen goes dark after only a few seconds, even after my lid closing technique. Last night, however, the screen stayed on, seemingly normally for some time, but this morning the display goes dark after only a few seconds.

The screen itself has no oddities, no dimness or color shifting, and the FlexView screen is still pretty bright. (I have another new one in the wings.)

Does this sound like an inverter issue, or possibly a lid sensor issue? Right now I'm using an external monitor with my trusty T60P.

rumbero
Junior Member
Junior Member
Posts: 451
Joined: Fri Mar 04, 2011 7:02 pm
Location: Barcelona, Spain

Re: Possible Inverter Issue?

#2 Post by rumbero » Tue Mar 31, 2015 1:57 pm

Sounds familiar, had the same issue before: the CCFL tube is slowly giving up. Time to either replace the display panel or the CCFL.

But instead of swapping the CCFL tube, maybe better try to replace it with an LED kit for peace of mind.
Broken T23 2647-9RG | A few 14.1" T61 Frankenpads | Two 15" Frankenpad T61+ with UXGA IPS Display

taichi
Senior Member
Senior Member
Posts: 574
Joined: Mon Oct 29, 2007 2:07 pm
Location: Los Angeles, CA

Re: Possible Inverter Issue?

#3 Post by taichi » Tue Mar 31, 2015 3:11 pm

If the CCFL tube was going, wouldn't the picture be getting dim? The screen is pretty bright. I would think that if the backlight was going that there would be some degradation of the picture itself, which is not the case.

I do have another, new FlexView UXGA screen as a replacement if needed.

theterminator93
Senior Member
Senior Member
Posts: 770
Joined: Fri Oct 11, 2013 7:45 pm
Location: Avon Lake, Ohio, United States

Re: Possible Inverter Issue?

#4 Post by theterminator93 » Tue Mar 31, 2015 3:14 pm

Easily rule out the inverter by swapping in your spare LCD panel to see if the problem goes with the panel. If so, it's the CCFL and your inverter is fine. :)
Daily: W520 i7-2860QM·Quadro 2000m·IPS FHD | T420 i7-2640M·NVS 4200m·IPS FHD | X220 i7-2640M | T601F T9900·NVS 140M·IPS UXGA
Wife's: T61p T9500·2010 FX570m·WUXGA | X220T i7-2640M
Others: T400·61p·61·60·43·42p|X41T·24·23·22|G41|A31p·22m|i1200|TransNote|380D|365XD|701C|755C

rumbero
Junior Member
Junior Member
Posts: 451
Joined: Fri Mar 04, 2011 7:02 pm
Location: Barcelona, Spain

Re: Possible Inverter Issue?

#5 Post by rumbero » Tue Mar 31, 2015 5:40 pm

taichi wrote:If the CCFL tube was going, wouldn't the picture be getting dim? The screen is pretty bright. I would think that if the backlight was going that there would be some degradation of the picture itself, which is not the case.
As i wrote, i once had the very same issue. The picture was perfectly fine and bright, but the CCFL tube was increasingly unable to maintain its light output and just turned off. This became worse over the span of several weeks and eventually it completely stopped turning on.

Replacing this BOE Hydis UXGA with my last remaining NOS replacement screen revealed that the very same inverter, which i suspected to be the main culprit, works just fine with the replacement display. This was about 8 months ago and i am currently typing these lines on the very same machine.
Broken T23 2647-9RG | A few 14.1" T61 Frankenpads | Two 15" Frankenpad T61+ with UXGA IPS Display

taichi
Senior Member
Senior Member
Posts: 574
Joined: Mon Oct 29, 2007 2:07 pm
Location: Los Angeles, CA

Re: Possible Inverter Issue?

#6 Post by taichi » Tue Mar 31, 2015 6:08 pm

I appreciate that last bit of information as I do not do my own repair, but go to a trusted repair shop. It's interesting that the failing CCFL doesn't diminish appreciably in brightness before biting the dust. I wouldn't have guessed that.

My replacement screen is also a Boe Hydis, bought long ago from this forum for just such an occasion as this.

GACrabill
Junior Member
Junior Member
Posts: 402
Joined: Thu Jul 22, 2004 11:26 pm
Location: Indiana

Re: Possible Inverter Issue?

#7 Post by GACrabill » Tue Mar 31, 2015 9:46 pm

taichi wrote:Then these instances of the screen going dark became more frequent, and then I discovered that by closing the lid and opening again the screen would come back to life. However, the instances of darkening now have increased to the point that the screen goes dark after only a few seconds, even after my lid closing technique. Last night, however, the screen stayed on, seemingly normally for some time, but this morning the display goes dark after only a few seconds.
Have you tried running the screen at one or two notches down from maximum brightness to see if the instances of going dark are noticeably reduced ?

Other threads have mentioned that if reducing the brightness level solves the going dark problem, then it is a failing CCFL in the screen. I have seen the problem twice where reducing the brightness level solved the going dark problem. In one case the owner didn't have me replace the screen until they were constantly running at the lowest brightness setting and barely able to see the screen unless it was pretty dark in the room.

taichi
Senior Member
Senior Member
Posts: 574
Joined: Mon Oct 29, 2007 2:07 pm
Location: Los Angeles, CA

Re: Possible Inverter Issue?

#8 Post by taichi » Tue Mar 31, 2015 10:45 pm

I was already convinced that the CCFL was failing before the test, and now my certainty has deepened. When I was able to lower the brightness to 5 (it wasn't easy to get the display to fire up at all) the screen has managed to stay on for the last 25 minutes.

So that clinches it. Thanks for and I all the advice guys.

Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “ThinkPad T6x Series”

Who is online

Users browsing this forum: el-sahef and 26 guests