• Hello, Guest! Welcome back, and be sure to check out this post for more info about the recent service interruption and migration.

Powerbook 140 screen weirdness and loud blaring noise

ßœœ

Active member
Got a powerbook 140 for free and while it is in very good cosmetic condition other than missing the port cover, it has some issues. When I plug it in (I'm using a universal power supply with the different settings and stuff you know the ones) and turn it on it makes a loud grating noise and the screen turns on and has a bunch of horizontal lines, and it just stays like that. I at first thought it needed recapping but I opened up the display and the caps look perfect. Maybe it still does, but from my experience with gamegears bad caps look like bad caps. If that is for sure what causes this, please let me know, but I just wanted to see if there's anything else I could try first!
 

AndyO

Well-known member
I'm no expert, but I doubt the issue with the screen coming on with horizontal lines and then staying like that is actually a problem with the screen itself. It seems more likely to me to be that the powerbook is not initializing.

My 180 did the same thing. Powering it up caused a startup chime, and the screen to display nothing but a few horizontal lines. It would sit like that for a while, either doing nothing or in some instances after several minutes the screen would gradually clear to a more normal white, then it would boot.

I opened it up, cleaned out a lot of dust and debris, and removed the RAM expansion board, after which it booted reliably every time. I have since replaced the RAM board, and when it is powered up now, it chimes, the screen goes blank with a few horizontal lines again, but after a second or two they clear, the screen comes up as normal, and it boots to the desktop.

I think this suggests that the screen you see is not unusual or indicative of a fault in itself. Rather that the powerbook is hanging up at or near the start of the initialization process.

It's the 'grating noise' that I think is the place to start, because obviously that isn't normal. It may be that what you're hearing is a damaged speaker turning the chime into that sound, but it seems quite possible it's the hard drive. Either way, my guess is that there's a fault that is preventing the powerbook from starting up. Try a reset first - unplug the power and leave it unplugged for several minutes, bend a paperclip into a 'U' shape so that it can press both the small/recessed reset and interrupt buttons, and press them both at the same time for 10 seconds. Then reconnect power and try booting again. When I did that on my 180, it changed the behavior to include the 'chimes of death', which at least gave me an error code.
 

ßœœ

Active member
I'm no expert, but I doubt the issue with the screen coming on with horizontal lines and then staying like that is actually a problem with the screen itself. It seems more likely to me to be that the powerbook is not initializing.

My 180 did the same thing. Powering it up caused a startup chime, and the screen to display nothing but a few horizontal lines. It would sit like that for a while, either doing nothing or in some instances after several minutes the screen would gradually clear to a more normal white, then it would boot.

I opened it up, cleaned out a lot of dust and debris, and removed the RAM expansion board, after which it booted reliably every time. I have since replaced the RAM board, and when it is powered up now, it chimes, the screen goes blank with a few horizontal lines again, but after a second or two they clear, the screen comes up as normal, and it boots to the desktop.

I think this suggests that the screen you see is not unusual or indicative of a fault in itself. Rather that the powerbook is hanging up at or near the start of the initialization process.

It's the 'grating noise' that I think is the place to start, because obviously that isn't normal. It may be that what you're hearing is a damaged speaker turning the chime into that sound, but it seems quite possible it's the hard drive. Either way, my guess is that there's a fault that is preventing the powerbook from starting up. Try a reset first - unplug the power and leave it unplugged for several minutes, bend a paperclip into a 'U' shape so that it can press both the small/recessed reset and interrupt buttons, and press them both at the same time for 10 seconds. Then reconnect power and try booting again. When I did that on my 180, it changed the behavior to include the 'chimes of death', which at least gave me an error code.
I ended up ordering an actual power adapter for it and it's quite confusing. Screen still being weird but the noise is gone. Here's a video with more info, if anything looks familiar to you I'd like to know! I'm stumped for the time being.
 

desertrout

Well-known member
Here's what I would do, in order of what is easiest and/or most likely a cause:
- try the power manager reset @AndyO described (i.e. pressing both the reset and programmer's buttons at the same time after a 10 second rest)
- verify the fuse at F1 (near the battery terminals on the main logic board), replace if open (part will depend on which kind of fuse it is)
- recap the display and inverter boards... the caps might look good, but they're pretty much guaranteed to not be. Here's a guide that will be relevant: https://mac84.net/web/macintosh-powerbook-160-lcd-display-recapping-guide/
- verify that the display cable is good working order (check for good seating at both ends of the cable, check for damage (they can crack near the display hinge))
- check for (and clean / repair) any corrosion damage near the battery terminals, check for shorts)

A couple of other comments after watching the video:
- The battery is indeed not required for startup
- It's better to have the RAM expansion removed while troubleshooting
- There is no boot menu on these machines, you do need a boot disk (floppy, external or internal HDD -- System 7.0.1 or later)
- By the symptoms, I would bet your HDD is dead or will stick again, but hard to know until you get a reliable boot sequence

Keep at it! Whatever the issue is, there's a good chance it's fixable. Aside from the displays, these machines have proven pretty robust.
 

ßœœ

Active member
Thank you for the tips! I'll give everything there a go and see what happens. Also, attached to the place inside the battery slots into is a small component, almost looks like a piezo, and when I first got the mac it's cable was disconnected. I reconnected it but it didn't seem to change much. I'm not sure what it is or if it's supposed to be disconnected or if it somehow just came undone which seems very unlikely considering its in a locking cable slot and in between two boards.
 

Attachments

  • 16408096034633945808113466127992.jpg
    16408096034633945808113466127992.jpg
    2 MB · Views: 6

desertrout

Well-known member
I believe that's the temp sensor / fuse for the battery compartment, not likely to be blown I don't think it's needed for operation or would cause any issues if disconnected. I don't think...... hmmm... maybe check it too to see if it's good.

In that pic I also see that the fuse at F1 is the SMD style (white with red lettering) - that's the fuse I suggested to check and see if it's open.
 
Last edited:

ßœœ

Active member
Tested f1 fuse, it's good! The battery fuse however if it is a fuse it's bad, not getting any continuity through it so maybe it's something else. I'll just leave it unplugged cause that's how it was. There seems to be a little corrosion on the battery terms so I'll dissolve that and get to recapping! (Whenever the caps arrive, was hoping i wouldn't have to order components but ehh.) Also gotta epoxy the screw sockets back on, both on right hinge are broken.
 

desertrout

Well-known member
So, I had to check for myself what's going on with that sensor or fuse... I'm pretty sure it's a thermal fuse... anyway, when disconnected it doesn't impact booting or operation of the PB I just tested it on (a 145), so it shouldn't be factor in your issue (just to rule it out).
 

ßœœ

Active member
So I did the recap, and now this happens:
Really not sure what to do here, help appreciated again, sorry for being totally incompetent with these things.
 

desertrout

Well-known member
Ah, frustrating. No need for apologies. :)

My first thought is that it looks like there's a short or an intermittent connection, but impossible to say where - could be the interconnect cable, the display cable, the power jack, or even the HDD cable. First, as always, double check your work (you're welcome to take a pic of what you've done and share it here, unless you're confident in it), and you say all connections are sound, so next I would test to see if the machine will boot with the top and bottom cases separated, like this:
Powerbook 140 laying on its side, display open

This is how I assemble and disassemble PB's, partly because I find it faster but also because I have found that sometimes unexpected things happen when the machine's all buttoned up and it's easier to troubleshoot this way. So now when reassembling I always do a series of three test boots:
  1. first separated like above,
  2. then together but unscrewed (if it POSTs then I will press machine together in different spots to see if anything happens - sometimes the location is important information),
  3. then if all good I'll screw it together and do a final boot. Sometimes it's just the wrong amount of pressure in the wrong place and this sort of thing can happen.
If the machine boots with the case separated, then that narrows down the possible causes quite a bit.

Otherwise, you will need to return to troubleshooting basics and work up from a baseline.

But before that, some other initial thoughts:
- is the HDD installed? Try booting with the HDD cable disconnected from the logic board
- try booting with the floppy drive cable disconnected from the logic board
- as mentioned before, troubleshoot without the RAM expansion
- did you verify the display cable is fully intact (no splits/cracks, common near the hinge) and securely seated at both ends? (the display end is kinda tricky imo)
- is the power jack secure? Does ground and power have good continuity with the rest of the board?
- triple check your connections, that they're secure and the right way around, any pins are straight, etc: there aren't many, and they're hard to mess up

Someone else PLEASE chime in as well!
 

ßœœ

Active member
Ok I've been kinda trying everything. I noticed it would boot if I disconnected the main cable, and i actually got it to do the startup sound by putting in the cable at an angle, so i know the issue is in the top half. I recapped the inverter board, replaced the cmos battery, and actually found i had installed three caps backwards on the screen so I flipped those too thinking that would fix it, but no change. I think I'm going to try to get the ribbon cable out and see if it is indeed cracked. I hope it isn't, but I'm sure I can get a replacement.
 

desertrout

Well-known member
When you say the 'main cable' do you mean the cable to the interconnect board? Or do you mean the display cable?
 

3lectr1cPPC

Well-known member
A bit of a long shot here, but try disconnecting the keyboard. It probably won't fix anything, but on my 145, I get a similar effect if I hold down keyboard keys. If I hold down any key and try to start the PowerBook, it does nothing. Then, if I release the key, I get a speaker pop, some screen effects similar to what you're seeing for just a second, and then it shuts off. Pressing power with no keys pushed after that starts the system. Perhaps there is a fault in the keyboard?

Again, this is all a bit of a long shot, but it's worth a try, right?
 

ßœœ

Active member
I tried it, it didn't change anything but good thinking! It would've made sense at least. I also checked the display cable, seems fine. Just gotta keep poking around.
 

desertrout

Well-known member
At this point I would start from the most basic and work my way up, progressively connecting things. Begin with just the logic boards and interconnect board - nothing else connected to the interconnect board. If you get a chime, then try with the display cable attached. Then the inverter / backlight. Then the keyboard cables. Then the floppy. Then the HDD. Something should reveal itself, isolating the component requiring further troubleshooting.
 

ßœœ

Active member
At this point I would start from the most basic and work my way up, progressively connecting things. Begin with just the logic boards and interconnect board - nothing else connected to the interconnect board. If you get a chime, then try with the display cable attached. Then the inverter / backlight. Then the keyboard cables. Then the floppy. Then the HDD. Something should reveal itself, isolating the component requiring further troubleshooting.
Just did all this, got the chime all the way until display, do it must be there. I'm gonna check the ribbon cable pin by pin with a multimeter, so that should be fun
 

desertrout

Well-known member
Just did all this, got the chime all the way until display, do it must be there. I'm gonna check the ribbon cable pin by pin with a multimeter, so that should be fun
OK. Shouldn't be too bad - hopefully it checks out. Quick question: did you clean the display board after recapping?
 

3lectr1cPPC

Well-known member
My 145's display didn't work at first after a recap until a VERY thorough (and careful) cleaning with IPA. If you can't find anything wrong with the cable, I would try cleaning up the PCB around the display until it's spotless. It also wouldn't hurt to clean inside the connector on the PCB where the display cable plugs in. Clean both sides of the board as well, once cap juice gets out of a capacitor, it really can go places!

Pre-posting edit: looks like @desertrout beat me to it! I'll put my advice here either way.
 
Top