loading

travelmate 2350 lcd backlight trouble

the lcd screen looses the backlight (inverter replaced) right afer boot-up (dos screen barely visible). If it is visible then only for a second or so and then with some magenta shade instead of black and white. Before replacing the entire lcd I'd like to rule out anything else that may cause this problem. The external video works fine. One other finding: When depressing the hybernation switch ever so slightly (without actually activating it) the lcd jumps back to live if only for a split second. Anybody have any ideas?

sort by: active | newest | oldest
rgb (author) 10 years ago
Thanks guys for your input. Given the situation I summized that it would be cheaper to get her an external (cheap) lcd monitor. I hate to give up but it really looked like I was going to throw more money at it than it was worth. Thanks again.
rgb (author) 10 years ago
Not ruling out Malware - The lcd cuts out during the bios check screen which would be before any MS software is executed. I asked my daughter if she updated the BIOS and she said no (I have to believe that). I reset the BIOS to defaults after booting with external video but the same thing keeps happening after that (using only lcd as display). Since the external video works I assume that the video card is working (integrated or otherwise). Booting of CD occurs after the problem already manifests itself (during Boot check). Why would toggeling the lid closing switch cause it to jump to live for a split second? This switch is soldered directly onto the MB. I'll review the simple wiring for shorts but non of the wiring runs even close to the lid switch (or trough it).
LasVegas rgb10 years ago
Okay. Good job diagnosing, BTW. Since it's occuring during POST, you're right to rule out malware or System software. Even so, we know it's not your screen or backlight or it would never work rather than shut off. Since reseting the BIOS didn't do it, next reset all of CMOS memory (aka PMU, NvRAM, etc.). Different brands have different procedures for doing this. If there's no internal battery, it could be as easy as removing both the battery and external power for 20 minutes. Booted off of the external display, try reinstalling the video drivers for your computer. You should be able to find them at Acer's website, or that of the chipset your computer uses. Try adjusting the LCD's brightness down a little (Something could be shutting off due to overdriving).
trebuchet0310 years ago
This EXACT same thing happened to a friend's 17" Toshiba with one minor difference. Sometimes on first start up - the screen would be fine for a few minutes. External video etc. worked just fine.

Toshiba (under his 4 year warranty), replaced the mobo. I guess that means the video card is integrated. They did not replace the screen (I marked it with a grease pencil before it shipped out).

Perhaps acer and Toshiba use the same/similar video cards?

I'd follow LasVegas first. If that does not work, and you're comfortable with disassembly -- look for a wiring problem (the whole gently pressing the hibernation switch thing).
LasVegas10 years ago
The fact that the LCD backlight is working at all rules out hardware. You probably have some malware causing your problem. To test this: 1) Enter BIOS (sometimes ESC, F1, F2) and reset to defaults. 2) On startup, press F8 to enter alternate boot menu. Select "Safe Boot" to see if the display works okay. 3) Try booting your Windows CD. If any of the above techniques resolve the problem for even just that one boot, your problem is Malware, a Virus or screwed up Registry. The easiest solution is to reinstall Windows from scratch.