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cnakai

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laptop screen still dim w/ NEW inverter board AND NEW lcd???

hi,

i have an IBM thinkpad A31 laptop and had the screen go dim on me.  The next step i took was to order a new inverter board and replace the existing one.  The screen is still dim.  By dim, i mean, i can still see my winxp desktop icons and such, but just very faintly.  I then went ahead and purchased a new lcd, which i replaced the existing one with.  I still get the same problem with both a new inv. board and lcd.  I'm able to view my laptop via external monitor with no problems.  I've also checked on the laptop itself for any dimming switches that i could toggle, but all looks good there too.  At this point, after replacing the inverter board AND lcd, i can't figure out what else would cause the screen to be faint.  In addition, i've checked the power settings in bios and within winxp and all looks good.  Any ideas on what else this issue could be due to?  Any help is most greatly appreciated! (stumped over here...)

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rindi
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bobo_tech

I bet the ribbon cable has a problem too.

I had the main cable going from the motherboard to the lcd fail on me once before.  Same issue, everything worked fine but the display was really dark and it wasn't the lcd or the invertor.
Was your second inverter brand new or used? Can you test its output with a voltmeter? It is high voltage AC so be VERY careful.
if it is very dim, then maybe the lid sensor is jammed, check to make sure that any mechanical switch is free or any magnetic sensor is not picking up stray nearby metal, maybe any funky metallic decorative sticker.
On a ThinkPad, the lid closure switch will completely disable the screen. It is not configurable.
OK, there are many models and i have only used a couple of T series.  anyway, does the display work during bootup or is it just dim in Windows?

Did it go dim after some event?  eg. the Fn+End keys may have been inadvertently depressed to adjust the brightness, if so Fn+Home increases brightness.
I have a very simple solution -You need a new lcd screen
Unfortunately, it could still be a motherboard issue.  I've witnessed the motherboard not feeding any voltage to the inverter and that would also cause a very similar symptom.  If that was the problem, the motherboard needs to be changed.