Thread
Colour Classic Not Booting After Correct Sequence & Recap
The answer may be obvious, but I received a non-working Mac Color Classic. I replaced the battery, turned the computer on, hit the power key on the keyboard. Nothing. Cleaned and recapped the motherboard. Nothing. It's the analogue board, perhaps? Will a recap do, or are there perhaps deeper issues with the CC that typically occur? Cheers!
A real easy check before you get any deeper... Some Macs don't boot without the PRAM battery back in... Try putting the battery back in and booting it.. Just a suggestion before you start looking at broken traces on the logic board or the analog/power board....
I mean a known good battery... And then make sure you really wash that logic board.. I use 91% rubbing alcohol in the tub with a clean new toothbrush to get in the little legs of the ic's... after scrubbing with the alcohol and toothbrush do a rinse with the bottle of alcohol... I usually douse my boards with it and let it sit for a little bit to break down any chemical residue on the board then start with the toothbrush.. As uniserver has mentioned before goo can get under the chips.. make sure all your caps have the right polarity going the right direction..
This is a known issue, and there are multiple threads on it. It involves a trace being rotten out near the PMU IC.
Brand new tested battery has been in the mobo from the outset (first thing I did). I also gave the whole board a clean using 99% isopropyl alcohol. The most I get out of the thing is a small hiss from the screen indicating that power is definitely flowing through the machine, but boot up of any description just ain't happening.
Techknight: I'll have a look for the thread and also for the rotten trace...
Techknight: I'll have a look for the thread and also for the rotten trace...
Thanks for the links! I attempted each of the pictured work-arounds. Still nothing. 
Do you have a hi-rez shot of the logic board, near that oscillator? Maybe someone can spot something for you...
Yeah. Sure thing. I haven't bothered removing the trace wire but will do once others have any suggestions. 
You might need to remove the PMU chip and take a look underneath it for eaten traces/vias.
Regardless. You have one of those oddballs that needs extensive troubleshooting to figure it out.
Regardless. You have one of those oddballs that needs extensive troubleshooting to figure it out.
Anyone see anything I don't?
you need to go over that whole board with IPA and a tooth brush i see nasty ness under many of those I/C.
the board need to be washed, cap goo is a serious problem with the Color Classic.
the board need to be washed, cap goo is a serious problem with the Color Classic.
I'm no electrician, but I would have to say that solder joint on C6 looks suspicious (I assume that to be some kind of diode. But I'm probably wrong. 
). The solder pad on the + marker looks fine. I'm talking about the one opposite of that.
Visually speaking that's really the only thing I can spot. You'll likely have to bust out some testing equipment like multimeters and stuff to find the problem.
). The solder pad on the + marker looks fine. I'm talking about the one opposite of that.Visually speaking that's really the only thing I can spot. You'll likely have to bust out some testing equipment like multimeters and stuff to find the problem.
Did you try powering up the analog board without the logic board in place?
Maybe just say screw it and find a 550 board to throw in there... vroom!
If I can find one, I most definitely would!!!Maybe just say screw it and find a 550 board to throw in there... vroom!
If I were you, I'd check everything in that section of the board. Look at where the vias go and make sure the appropriate components on the top and bottom all have continuity through the vias with a multimeter. I did this on mine by taking a picture of the top and bottom, and color coded the vias. If the power key on the keyboard doesn't work, there's a decent chance it has something to do with the circuit nearby the CUDA chip (U7).
I had a similar problem with my CC, just one corroded via prevented it from starting up at all: https://68kmla.org/forums/index.php?/topic/24740-color-classic-no-power-issue-debunked/?p=270845
Thanks for the replies, I'll have to dig out the multimeter and figure out where to begin. U7 sounds like a good shout. I think I'll remove U8 as well just so I can remove any gunk from underneath it - U7 had quite a bit. It's annoying that I can't immediately see any rotten bias - that would make my job considerably easier. Any tips or links to using a multimeter for this task? Cheers.
I had the same problem with my CC after recapping. I washed/scrubbed it fully in IPA and then flushed with distilled water, after that it powered on correctly and now works fine.
You really need to flush out all the crap under the chips, I didn't need to remove any chips or do anything crazy.
I'm not sure why but the CC is worse than the LCs it seems.
You really need to flush out all the crap under the chips, I didn't need to remove any chips or do anything crazy.
I'm not sure why but the CC is worse than the LCs it seems.
Well, I've just attempted a dishwasher clean of the motherboard followed by a 99% isopropyl bath. Will let that fully dry and will try again. My multimeter arrives tomorrow, so I'll start the arduous task of testing each via line by line...
Massive update (well, relatively speaking):
Following mwdmeyer's advice, I washed the motherboard in the dishwasher, dried it, rinced in 99% isopropyl alcohol, dried it and left it in a casserole bowl filled with rice overnight. Today, it boots!!!
Any idea how to adjust the tint so it's less 'pink'? Please tell me I don't need some special tool. Please say I can use a random screwdriver or bit.
Following mwdmeyer's advice, I washed the motherboard in the dishwasher, dried it, rinced in 99% isopropyl alcohol, dried it and left it in a casserole bowl filled with rice overnight. Today, it boots!!!
Any idea how to adjust the tint so it's less 'pink'? Please tell me I don't need some special tool. Please say I can use a random screwdriver or bit.
Okay, new update. I just used a screwdriver and easily manipulated the adjustment controls on the back of the CC. I've got a new issue. No matter what I do to the colours, focus, etc., some of the colours (primarily blue) look really washed out. If I raise the red levels, the whole screen goes a rosy color like before.
You can see in this image what 'purple' looks like. Any suggestions?
You can see in this image what 'purple' looks like. Any suggestions?
you adjusted the wrong controls. There are drive controls, and contrast controls for each color.
I definitely had a go at every adjustment control on the machine, but can't hurt to keep trying...
There is a special process for the alignment. Also, it could be a bad solder joint or capacitor in one of the 3 color circuit paths. These ABs are known for bad caps and solder joints.
Time for some hirez pictures of the AB solder joints! 
Hello again. I'll be in a position to recap the A/B sometime next week. Just had a quick question before I get started. Are there any known differences between North American and European boards? I only ask because I want to use the very helpful capacitor map and list already produced (scroll down to iMic's post):
https://www.thinkclassic.org/viewtopic.php?id=202
I think iMic's CC is European, but I thought I'd check. For the record, I've got a European model - indeed a 'Colour Classic'! Many thanks!
https://www.thinkclassic.org/viewtopic.php?id=202
I think iMic's CC is European, but I thought I'd check. For the record, I've got a European model - indeed a 'Colour Classic'!
Many thanks!Yes, iMic's runs at 220, but I am pretty sure the CC is 110/200 auto switching. Should say on the back. If so, then yes for sure they are all the same.
did you re-cap the analog board?
i would re-cap the analog board, follow iMic's image, then re-adjust those pots.
i would re-cap the analog board, follow iMic's image, then re-adjust those pots.
Hey uni, that's exactly what I'm aiming to do sometime next week. I've looked carefully at the analogue board and I don't see any major surprises (unlike iMic's first encounter), but it's very likely a re-cap job that's needed to fix the colour issues. Once that's done, I'm hopeful that everything will be squared away. I've got an LC 550 motherboard on its way, which is great, but it also means that my restoration of the CC's mobo may have been a bit of a waste of time! Oh well, if the 550 works out, maybe someone would be interested in the original. Anyway, I'll keep the thread updated once I've re-capped the analogue board. Cheers!
Oh, and unity, you were right!
Oh, and unity, you were right!
Just finished recapping a CC yesterday and it wouldn't boot. I resoldered any suspect points on the analogue board and checked the vias mentioned in here... Then I put a small 3V watch cell where the (dead) PRAM battery was... and it booted. Yay! This puppy is maxed at 10MB, i installed a spare 256 VRAM card and FPU.
Also Lazarus, you are missing the green channel completley. I'd put it back to the "rosy" colour and focus on getting any hint of green to appear.
Also Lazarus, you are missing the green channel completley. I'd put it back to the "rosy" colour and focus on getting any hint of green to appear.
Great work on the CC revival! I'm glad everything is looking good for you. In regards to my colour issues, I'll likely recap the analogue board and see where I'm at after that. You're correct, though, I'll likely have have to reset the colours back to where they were, as my adjustments will have flooded the screen with blues to overcompensate for the reds. The green channel seemed to work, but not well. Perhaps that's a cap issue. Will update soon!
Well, I replaced every capacitor on the analogue board but one (I bought the wrong physical size, and it doesn't fit) AND the CC has normal colours again!!
Can someone remind me of the utilities available to calibrate the colour of the screen? Cheers!
Can someone remind me of the utilities available to calibrate the colour of the screen? Cheers!
Yea, you use an adjustment tool and tweak the drives until the color is good.
I remember reading in a couple places of an official Apple utility that helps you calibrate your screen as well as a third-party app. Anyone know what either of those is called? Thanks!
good job man!