I also vote for the PRAM. Branchus Creations is an amazing channel if you're into vintage Mac repairs. He's bound to have lots of streams where he repairs LC IIs.
Funny enough, I had the same PRAM issue on a 2010 Macbook Pro. The battery had fully discharged and the system would not let the unit power up or even charge... until a key combo to reset the PRAM. I think this is the same as resetting the CMOS. Maybe see if there is a key combo for that unit? Great vid.
I just restored a LC II with the same problem: leaked capacitors. It works fine, but I don't understand why. Here is the story. I've found this old Macintosh LC II in a storage hall. I connected it to its original monitor, switched it on and after a beeping sound i've got a grey screen (not black), but nothing else, no boot, nothing. I opened the "pizza box" ;) and the corner with the caps was covered by a yellowish stuff. It looked like all them leaked. By removing the board one of the cap fell off, due to corrosion. I had little hope. What I did next was to put the mother board in the dish washer, twice. First time without detergent, second time with, since after the first time I didn't see any improvement. I rinsed the board with distilled water, dried it up with a hair dryer and let it rest for the night. The next day I had a closer look at the board with a microscope. All the stains were gone, but I saw the same greenish stuff around the chips. Not good. I then sonicated the board. Luckily the dirty corner fitted in my ultrasonic device. I added a teaspoon of ultrasonic cleaner and sonicated the board for 7 minutes. I rinsed the board with distilled water and let it rest for a night. This time the board looked much better. Before ordering new caps and without any hope I reassembled everything, switched it on and...bang, it booted! It showed me the desktop as it was left by the last user, a well known astronomer by the way. So, I didn't replace the leaked caps and the missing cap is still missing. Why does it work?!
Thanks for the mentionn =D As others have said - PRAM battery, and I vaguely remember some small IC near ports at the back that does something with reset. You could probe the reset pin on the 68030, and also check its BERR and HALT pins.
I remember my old University chucking these in the skip back in 2001. I found an old LCII, some spare SIMM ram and spare tdk smps. The PRAM (1/2 AA size) battery can stop it from booting up if the battery is flat, and they often leak also over many years.
@@CRG Could try using a 3 volts psu or 1/2 AA battery in the PRAM battery slot. If the battery is removed, then the PRAM may need to be reset as others have said below, before it will boot.
I know this is an old video but i have found that lifting the egret and DFAQ chip and cleaning underneath (also checking for bad traces) is usually the culprit since the cap juice corrodes under those chips..
I found your channel a few weeks back and am really enjoying your videos. Your accent and phrases remind me of John (aka The Stig from Newtownards) who used to have a channel.
I'm in Dundonald so only up the road from Newtownards. Thanks for the kind words and glad to hear your enjoying the videos. Psycho Fox is a great master system game btw. I had it back in the 90s but over the years it's been lost. Would love to get another copy.
Also some macs used the metal shield inside the case as a ground plane so they won’t start unless all the parts are installed in the case with the lid closed.
Awesome video! I have a Macintosh LC II too, and I've been meaning to service it. This video motivates me to service it, as the battery leaked and a couple of caps leaked too. Thank you for this video! Please, keep up the good work!
Fixed my aunt's LCII a few (yes few) years ago. Same problem, all the electrolytics have leaked, weird noises coming out of the speaker, black screen (got a white screen once). Replaced all the caps, still black screen (at least the noises were gone). Went to remove the PSU in order to check that, I saw another cap hiding under the power supply cable. Replaced that - fixed it. Then I installed some games on it.
Great vid. Could be just the cap juice has eaten too many components. That said, the following may be worthwhile checking: 1. Some of these macs dont run without the Lithium battery installed 2. One of either the LC II or LC III mobos had a revision with a silkscreen error where one cap polarity is marked wrong. This affected my repairs in the past. If you have a before pic of the mobo it may be worth checking. 3. Although the voltages are good, check the inside of the PSU. Those caps are likely in a bad shape and may not be able to provide current under load. The Astec PSUs have many issues IIRC. Hope you get it working. Oh that HDD is probably banjaxed due to the "sticking rubber grommet" problem where a degraded rubber gromet causes the HDD head to stick when reaching the spindle.
Oh and @CRG Check the audio chip on the top left, sometimes it not being properly connected can scupper the repair. On one of my LC IIs it took forever for me to realise.
I have the same problem on my LCII no sound, black screen. Last time i tested it was 2009 and it worked. My LC1 (with 68020 processor) works without problems even caps have not leaked.
I'm not giving up on this one. I've got a new battery on order just incase that's the issue but I'm not convinced. I think I'll swap out those bus transceivers just on the off chance but it may be the ROMs.
I guess you may have checked these, but here goes. Check the power supply, check the reset circuit, are any of the chips excessively hot, you can download the ROMS so check they are not corrupt. Try different RAM modules.
I don't suppose you'd have a link to the ROMs? I've checked everything else you mentioned and it's all fine but keep the suggestions coming, it's always welcome.
Battery? There is conflicting information about how important a battery is for getting these systems to boot, but a lack of one could garble up the PRAM. At least it would be an easy enough thing to test.
The capacitor plague of the 90s (SCS shit capacitor syndrome) just gets worst. Even just a few years ago a cap job would have fixed this - but the leakage is just a disaster now. My SE30 was on the brink until a complete ultrasonic clean due to (probably) corrosion under the SMD ic’s.
I wonder if in another 30 years will all these caps we are fitting now have leaked. An ultrasonic cleaner is something I'd love to add to the arsenal of equipment although expensive so it's way down the list. The problem here could still be leaked cap juice but I get the impression it's something failed.
Looking inside the PSU there is no sign of leaky caps but its a known problem so they probably need swapped out. For all it costs no harm in trying it.
Adding a battery made no difference. I've put this machine away for now as I really need another working board to compare to but if I can find another I will come back to this.
I also vote for the PRAM. Branchus Creations is an amazing channel if you're into vintage Mac repairs. He's bound to have lots of streams where he repairs LC IIs.
Thank you for the tip!
Some of these old Macs won't power on without the PRAM battery. Worth a try since it's dead anyway.
I've ordered some batteries and hopefully it is that simple. I'll put a post on the community tab either way just so everyone knows.
@@CRG Bench power supply @ 3.6 or 3 rechargeable (1.2v) AAs in series would get you there without the wait ;)
Funny enough, I had the same PRAM issue on a 2010 Macbook Pro. The battery had fully discharged and the system would not let the unit power up or even charge... until a key combo to reset the PRAM. I think this is the same as resetting the CMOS. Maybe see if there is a key combo for that unit? Great vid.
@@CRG i think it will be battery issue as i remmber seeing something about it in someone else,s video hopefully it will solve the issue .
I just restored a LC II with the same problem: leaked capacitors. It works fine, but I don't understand why. Here is the story.
I've found this old Macintosh LC II in a storage hall. I connected it to its original monitor, switched it on and after a beeping sound i've got a grey screen (not black), but nothing else, no boot, nothing.
I opened the "pizza box" ;) and the corner with the caps was covered by a yellowish stuff. It looked like all them leaked. By removing the board one of the cap fell off, due to corrosion. I had little hope.
What I did next was to put the mother board in the dish washer, twice. First time without detergent, second time with, since after the first time I didn't see any improvement.
I rinsed the board with distilled water, dried it up with a hair dryer and let it rest for the night.
The next day I had a closer look at the board with a microscope. All the stains were gone, but I saw the same greenish stuff around the chips. Not good.
I then sonicated the board. Luckily the dirty corner fitted in my ultrasonic device. I added a teaspoon of ultrasonic cleaner and sonicated the board for 7 minutes. I rinsed the board with distilled water and let it rest for a night.
This time the board looked much better. Before ordering new caps and without any hope I reassembled everything, switched it on and...bang, it booted! It showed me the desktop as it was left by the last user, a well known astronomer by the way.
So, I didn't replace the leaked caps and the missing cap is still missing. Why does it work?!
Thanks for the mentionn =D As others have said - PRAM battery, and I vaguely remember some small IC near ports at the back that does something with reset. You could probe the reset pin on the 68030, and also check its BERR and HALT pins.
Thanks for the tips, I'll take a look at those pins. I've ordered a few batteries, here's hoping its that simple.
I remember my old University chucking these in the skip back in 2001. I found an old LCII, some spare SIMM ram and spare tdk smps.
The PRAM (1/2 AA size) battery can stop it from booting up if the battery is flat, and they often leak also over many years.
I must come back to this system at some point and give it another go.
@@CRG Could try using a 3 volts psu or 1/2 AA battery in the PRAM battery slot. If the battery is removed, then the PRAM may need to be reset as others have said below, before it will boot.
Bad with the good, nice to see it from all angles.
7:30 Solder ninja skill unlocked.
I know this is an old video but i have found that lifting the egret and DFAQ chip and cleaning underneath (also checking for bad traces) is usually the culprit since the cap juice corrodes under those chips..
I found your channel a few weeks back and am really enjoying your videos. Your accent and phrases remind me of John (aka The Stig from Newtownards) who used to have a channel.
I'm in Dundonald so only up the road from Newtownards. Thanks for the kind words and glad to hear your enjoying the videos.
Psycho Fox is a great master system game btw. I had it back in the 90s but over the years it's been lost. Would love to get another copy.
Adrian’s digital basement might know! I don’t know him but he does Mac and basically all 80s early 90s Atari,Mac and 286.386.486 computers
Worth a try
Also some macs used the metal shield inside the case as a ground plane so they won’t start unless all the parts are installed in the case with the lid closed.
I didn't know that, thanks for the tip. I really should revisit this machine sometime as I'd like to get it working.
I’m loving the two iron technique
Awesome video! I have a Macintosh LC II too, and I've been meaning to service it. This video motivates me to service it, as the battery leaked and a couple of caps leaked too. Thank you for this video! Please, keep up the good work!
I'm pretty sure a fresh PRAM battery is needed to boot these. Zapping the PRAM is also possible with CMD + OPT + P + R.
It won't boot without it !
Fixed my aunt's LCII a few (yes few) years ago. Same problem, all the electrolytics have leaked, weird noises coming out of the speaker, black screen (got a white screen once).
Replaced all the caps, still black screen (at least the noises were gone).
Went to remove the PSU in order to check that, I saw another cap hiding under the power supply cable. Replaced that - fixed it. Then I installed some games on it.
I have two Quadra's I've been putting off tackling re-capping with those types of caps. Maybe I'll try that dual iron technique instead of the twist.
Great vid.
Could be just the cap juice has eaten too many components.
That said, the following may be worthwhile checking:
1. Some of these macs dont run without the Lithium battery installed
2. One of either the LC II or LC III mobos had a revision with a silkscreen error where one cap polarity is marked wrong. This affected my repairs in the past. If you have a before pic of the mobo it may be worth checking.
3. Although the voltages are good, check the inside of the PSU. Those caps are likely in a bad shape and may not be able to provide current under load. The Astec PSUs have many issues IIRC.
Hope you get it working.
Oh that HDD is probably banjaxed due to the "sticking rubber grommet" problem where a degraded rubber gromet causes the HDD head to stick when reaching the spindle.
Oh and @CRG Check the audio chip on the top left, sometimes it not being properly connected can scupper the repair. On one of my LC IIs it took forever for me to realise.
I have the same problem on my LCII no sound, black screen. Last time i tested it was 2009 and it worked. My LC1 (with 68020 processor) works without problems even caps have not leaked.
I'm not giving up on this one. I've got a new battery on order just incase that's the issue but I'm not convinced. I think I'll swap out those bus transceivers just on the off chance but it may be the ROMs.
Some older Macs will not boot without a clock battery installed.
Hi ! try resoldering the video output chip AH8079; it helped me on 6100. The IC U10 - clock and service controller, resets the signal to
I guess you may have checked these, but here goes. Check the power supply, check the reset circuit, are any of the chips excessively hot, you can download the ROMS so check they are not corrupt. Try different RAM modules.
I don't suppose you'd have a link to the ROMs? I've checked everything else you mentioned and it's all fine but keep the suggestions coming, it's always welcome.
Battery? There is conflicting information about how important a battery is for getting these systems to boot, but a lack of one could garble up the PRAM. At least it would be an easy enough thing to test.
Yes there are some models that dont work without a battery but im not sure whitch. My LC1, CC and SE/30 works all without a battery.
I've ordered batteries, will let you know when they arrive.
The capacitor plague of the 90s (SCS shit capacitor syndrome) just gets worst. Even just a few years ago a cap job would have fixed this - but the leakage is just a disaster now.
My SE30 was on the brink until a complete ultrasonic clean due to (probably) corrosion under the SMD ic’s.
I wonder if in another 30 years will all these caps we are fitting now have leaked.
An ultrasonic cleaner is something I'd love to add to the arsenal of equipment although expensive so it's way down the list. The problem here could still be leaked cap juice but I get the impression it's something failed.
Hot Tweezers are what you want.
You could add a red LED :)
Maybe a long shot but the 12v rail was low. Under load it will be lower...I guess I'm saying don't rule out the PSU pal!
Looking inside the PSU there is no sign of leaky caps but its a known problem so they probably need swapped out. For all it costs no harm in trying it.
Is it one of those weird things that must have a keyboard attached to power on?
Unfortunately not, tried that and no difference. Thanks for the tip though, always appreciated.
-Macintosh Leaky Caps-
I'm just waiting for someone to ask : "has it been recapped?" (reference to the Commodore Amiga group on Facebook)
It is a go to phrase these days, this one did need it but it's obviously not the only issue.
Only LC1 boots without battery!
Adding a battery made no difference. I've put this machine away for now as I really need another working board to compare to but if I can find another I will come back to this.