T400 Brightness cannot be changed after standby/resume-cycles [ Edited ]

[Izmi]

Often, when I hold down the Fn-key while pressing the Home-key or the End-key, the display brightness does not change. Also, in these cases the green brightness info-bar is also not displayed. Though, other Fn-key combinations work like Fn+F7 or Fn+ScrLk.

After a fresh boot, it works. The problem seems to be related to power management since it occurs often after standby/resume-cycle or a hibernation/resume-cycle or a change from running on AC to running on battery .

This happens on a T400 running Vista 32. Lenovo software is up-to-date, AFAIK.

[gokalp]

I have the same problem, too. It happens after a few sleep cycles on a T400 with vista 64.

Does anybody have any suggestions?

[rhuber]

I am facing the same problem and would be very happy about a solution (Vista64)

[rdharper]

Happens infrequently... coming out of standby.  And with decreasing frequency.  For instance, I use the lid trigger to go into standby, and come out of it.  Typically 10 times a day.   I can not remember when the last time I didn't have adjust capability. 

I have the default brightness set a bit high, so I will almost always drop it a notch. 

Point is, I've had the problem... did nothing to "fix it"  that I'm aware of.  Which means it will be back at some point.

[RealStranger]

This problem seems to be quite usual for the T400 ... but it shows up not too often.

What helped me, anytime I faced the problem, is closing the lid to turn off the display and open it again. A little problem here is using this to send the notebook to standby

Greetz!

M.T.

[joer80]

I have had problems with my t500 brightness not being adjustable with the keyboard, but it works via powermanagement..  Although it works right now, I also did nothing to fix it.

[RealStranger]

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joer80 wrote:
I have had problems with my t500 brightness not being adjustable with the keyboard, but it works via powermanagement..  Although it works right now, I also did nothing to fix it.

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Seems to be a quit "funny" bug ... I could not change brightness with powermanagement ^^

Greetz!

M.T.

[Izmi]

The problem seems to be resolved by recent updates.

Message Edited by Izmi on 02-24-2009 03:25 PM

[andrewfong]

I'm having this issue too, but since the Thinkvantage System Update no longer works, I can't have it automatically download any updates. I went Lenovo's site to look for things to download manually, but there are a lot of different options, none of them specifically referencing the brightness issue. So far I've tried the power management related ones, but no dice. Anyone have any suggestions?

And a note to Lenovo: Disabling System Update while you're making whatever changes it is you plan to plan is pants-on-head-stupid. 

[wonderbread57]

I have the same issue that I can't adjust the brightness after sleep sometimes. My system is up to date Vista wise. Not sure what to do. Trying to adjust the brightness in the power manager does nothing.