Powerbook 100 with blue screen of death pls help

[macmaniac]

A friend gave his old powerbook 100 to fix. When I boot it, it doesn't chime and it displays a blue screen. I recaped the whole LCD and almost every cap on the motherboard except the two on the left. Decided to use through hole caps instead of SMDs because I couldn't find anyone selling them, but they still should do the job. Using a 6V 3A power adapter because I don't have the original. Please let me know if you have any tips.

 

[finkmac]

what lcd caps did you use

also those solder joints look ugly. are you using a good iron, decent solder, enough flux, and the proper heat?
did you clean off the old cap residue?

actually, what brand of capacitors is that even? sanco? is that trustworthy?


come on man. don't.


what the heck is this.

here's my digikey cap list. i'd go with that instead.

 

[macmaniac]

what lcd caps did you use

also those solder joints look ugly. are you using a good iron, decent solder, enough flux, and the proper heat?
did you clean off the old cap residue?

actually, what brand of capacitors is that even? sanco? is that trustworthy?

View attachment 78441
come on man. don't.

View attachment 78442
what the heck is this.

here's my digikey cap list. i'd go with that instead.

All of the corrosion and cap juice is cleaned from the board with IPA, and all of the caps are properly connect because I tested them with my multimeter. I know it looks kinda jenky but I twisted them a bit so I can reassemble the laptop. Nothing seems shorted

 

[finkmac]

what happens if you hit the reset or nmi buttons? also have you adjusted fiddled with the contrast/brightness?

 

[twelvetone12]

A couple notes:
* No sound or boot chime could mean C6 is not properly connected
* I personally would be wary of using caps soldered "on air" like that with long non insulated leads, it is easy for something to touch and make the situation worse
* Check the three inductors in the lower corned of the board (the dark grey round ones) and make sure they are not open, IIRC two of them are part of the minus voltage for the screen bias. There are also a bit more components there to check if they are ok
* Lastly make sure you have the minus voltage for the screen bias, you will probably need to check the schematic for that. There is also a test point to measure it.

Hope it helps!

 

[imactheknife]

Actually looks like the rear polarizer is cooked being burnt orange. Hard to say what can be done. The blue screen of death is notorious for these machines.

 

[finkmac]

nah it's probably not orange. just a bad picture

 

[macmaniac]

A couple notes:
* No sound or boot chime could mean C6 is not properly connected
* I personally would be wary of using caps soldered "on air" like that with long non insulated leads, it is easy for something to touch and make the situation worse
* Check the three inductors in the lower corned of the board (the dark grey round ones) and make sure they are not open, IIRC two of them are part of the minus voltage for the screen bias. There are also a bit more components there to check if they are ok
* Lastly make sure you have the minus voltage for the screen bias, you will probably need to check the schematic for that. There is also a test point to measure it.

Hope it helps!

Thanks a lot I will try it later. The very weird thing is that if I remove the CPU card it either does the same or the blue screen turns on and the speaker makes a weird buzzing sound for a second and it turns off

 

[twelvetone12]

I'm not sure what is the default state without the CPU board, IIRC the screen should be fully white? I can test it on my machine if I have a moment. Also make sure the caps on the display are all making good connection!

 

[macmaniac]

I'm not sure what is the default state without the CPU board, IIRC the screen should be fully white? I can test it on my machine if I have a moment. Also make sure the caps on the display are all making good connection!

I test and all the caps on the LCD are making good contact, I'm having nightmares that the CPU card is faulty

 

[macmaniac]

what happens if you hit the reset or nmi buttons? also have you adjusted fiddled with the contrast/brightness?

Contrast and brightness knobs do nothing. If I press both of the reset buttons it turns off

 

[macmaniac]

I think the problem is that the LCD is getting underpowered because I get a reading of 1.1V, probably what's going on is the display is displaying absolutely nothing because it's underpowered and the backlight is just on

 

[Byrd]

Search on these forums for replacement of inductors near where a lot of cap goo gets out (doesn’t always but explains black screen, I was able to resurrect a PB100 once replaced a couple of weeks ago). And clean up your recap work, shorter legs, if you can clean the whole board extensively with IPA, electronic cleaning solvent will also help. Good luck

 

[macmaniac]

Search on these forums for replacement of inductors near where a lot of cap goo gets out (doesn’t always but explains black screen, I was able to resurrect a PB100 once replaced a couple of weeks ago). And clean up your recap work, shorter legs, if you can clean the whole board extensively with IPA, electronic cleaning solvent will also help. Good luck

Inductors are closed, I don't think they are the issue in this case

 

[macmaniac]

what lcd caps did you use

also those solder joints look ugly. are you using a good iron, decent solder, enough flux, and the proper heat?
did you clean off the old cap residue?

actually, what brand of capacitors is that even? sanco? is that trustworthy?

View attachment 78441
come on man. don't.

View attachment 78442
what the heck is this.

here's my digikey cap list. i'd go with that instead.

After a full recap of the motherboard shortining the legs of the caps this time instead of it booting up immediately when I plug it in, it started to power on normally by pressing the space bar and 5V to the LCD have been restored, but still blue screen and no chime