TAM with white screen

[plb007]

Hi, 

I just tried to reboot my 20th anniversary macintosh this sunday. It seems to boot right, but the screen stays white. I'm pretty sure it boots fine because it reacts to volume switch, birthness and power off. The last time it booted was less than 1 years ago. No changes (except powering down for this period). I tried the usual stuff (NVRAM, reset, battery check, ....) without any luck. I've made a video showing to process. Starting - waiting the TAM to boot, green light, actual booting, controls working, powering down. 



View attachment IMG_0991.MOV

 

[bibilit]

I will remove all cards from the Logic Board and try again.

Can be the screen also or the small board connecting logic board and screen

 

[Byrd]

Usually the white screen suggests just LCD failure, my experience with the analogue to video boards between the TAM motherboard and LCD is that the LCD usually works with artifacts if this particular board is faulty.  I'd reseat cables as suggested, and if all else fails look for a junker PowerBook 3400 with good LCD - it is a straight swap.

 

[plb007]

I'll try to find a 3400 for spare. How can you explain the LCD failure ? The backlight is still working well. Which part of the LCD screen is subject to fail ? 

Thanks for the info. 

 

[Byrd]

Wish I knew - the "white screen of death" is common in TFT LCD panels - you'll find similar reports in comparable machines of the day.  Almost always the fix was to replace the panel.  Still doesn't stop you reseating and cleaning cables, connectors in hope this fixes the problem.

... I have to take apart my TAM too soon, the floppy drive has flaked out - good to have a 3400c parts box on hand

 

[Unknown_K]

I'll try to find a 3400 for spare. How can you explain the LCD failure ? The backlight is still working well. Which part of the LCD screen is subject to fail ? 

Thanks for the info. 

Built into the panel  LCD controller board I would think. Could be bad caps.

 

[plb007]

An 3400c screen is coming for the swap. I'll take you informed of the result. 

Regards

 

[bibilit]

I found the post i made a couple of years ago when i replaced the screen myself

 

[plb007]

Hi guys, I fixed the problem by replacing the screen with an old 3400 screen. Not a simple procedure, I broke two latches from the TAM, but everything went well.




 


Thanks for the info. 

 

[plb007]

For those who are interested, here's a picture of the screen from the TAM and from the 3400c, not the same supplier. It might be different from country (I live in Belgium !)