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Kyle McKuen
July 8th, 2012, 07:55 PM
When you plug it in and press the on button it doesn't turn on. the fuse in the power supply is intact.

Is it a common problem for these power supplies to not work or is it just mine? Is there a way it can be fixed without getting another
power supply?

NeXT
July 8th, 2012, 08:43 PM
Well if you have not recapped the IIci itself then yes, it is known for the power supplies to go TU.

RWallmow
July 8th, 2012, 10:05 PM
Well if you have not recapped the IIci itself then yes, it is known for the power supplies to go TU.
Agreed, bad caps seem to plague Macs of the late 80s/early 90s vintage especially heavily, look for caps that have leaked out onto the board. The goo that has oozed onto the board can eat away traces, I would clean it up good to prevent further damage. Simple iso-alcohol does a decent job cleaning the goo, just be sure to fully dry everything (if in doubt let it sit a week, better safe than sorry).

If you can find caps of similar values (even if they are a different package), it's not THAT hard to re-cap a mac, so long as you are comfortable soldering.

geoffm3
July 9th, 2012, 11:19 AM
When you plug it in and press the on button it doesn't turn on. the fuse in the power supply is intact.

Is it a common problem for these power supplies to not work or is it just mine? Is there a way it can be fixed without getting another
power supply?

I had the same problem with my IIci... but the problem was with the caps in the poweron/startup circuit on the motherboard. There is a schematic floating around with the values. Some of the electrolyte leaked out of the old caps and corroded some of the solder around some of the chips in the startup circuitry as well that I had to reflow/cleanup. It mostly works right now, except that the system will turn on automatically when I apply power to the system, every subsequent powerdown/startup (via the software shut down/startup) works fine though.

applefreak
July 10th, 2012, 09:23 AM
or

the 5V trickle

http://www.shobaffum.com/iici/trickle.pdf

olePigeon
July 11th, 2012, 08:32 PM
IIci motherboard is nice and open, it's really easy to recap. Even I could do it, and I'm horrible at soldering.

Chromedome45
November 4th, 2015, 03:35 PM
Hate to awaken the dead here but just acquired a IIci and am having the no power symptom. Problem Appears to be on the mainboard. I did a bypass by wiring pin 9 to 10 on the power connector and the power supply did turn on. So my thinking is the logic board startup circuit. Any ideas?

geoffm3
November 4th, 2015, 04:52 PM
Hate to awaken the dead here but just acquired a IIci and am having the no power symptom. Problem Appears to be on the mainboard. I did a bypass by wiring pin 9 to 10 on the power connector and the power supply did turn on. So my thinking is the logic board startup circuit. Any ideas?



Yep. There's a schematic of the circuit floating around. Replace all the caps and check the solder joints of the related components. On mine the electrolyte leaked out of one and corroded all the way through the solder joints on over of the 74xx ics... It swept right off the board when I brushed over it with some running alcohol.

Chromedome45
November 4th, 2015, 06:09 PM
Well now this is odd. I left it plugged in and now it's running!? I guess that trickle charger woke up. Oh what position should the power button on the back be in? Out or in?
When I press the keyboard power key? It stays on. It is currently in the in position.

Yeah geoffm3 I was going to spray it down with ISO alcohol and use an acid brush to clean up around the electrolytic caps. Just in case.

Chromedome45
November 4th, 2015, 06:29 PM
Also noticed on power on no chime. well will mess with it more tomorrow.

olePigeon
November 5th, 2015, 07:41 AM
You really should recap it.

Chromedome45
November 5th, 2015, 08:32 AM
I intend to ordered caps for logic board this morning from Digi-Key. I noticed a few of the surface mount 47uF caps are bulging and they have some electrolyte on the board. I cleaned those up with ISO Alcohol to keep the fluid from spreading.

GiGaBiTe
November 6th, 2015, 07:14 AM
The leaking electrolyte can damage traces and the pads under the capacitors so it's best to remove them ASAP. I got to my LC III a bit too late and electrolyte seeped between the board layers under some SMT caps and started de-laminating the board. I managed to work around the damaged areas with bodge wires but it's probably only a matter of time before the electrolyte chews through deeper layers and ruins the board.

raoulduke
November 6th, 2015, 09:55 AM
People tend to be big on recapping the motherboard, but that's not always the issue. When you turn it on and it seems to not power on for 10 minutes, do you hear a faint clicking noise from the power supply? If so you should probably recap the PSU first, whether or not you recap the logic board. You should probably recap the PSU anyway, though, as others have mentioned.

Chromedome45
November 8th, 2015, 03:05 PM
Caps removed. All traces underneath were good and cleaned with iso alcohol installed replacements. Working fine now. Boot chime etc. Many thanks for the suggestions. 8 surface mount aluminum caps were installed 4 in the startup circuit and 4 in the sound area. Also UE13 74HC132 in startup circuit

In this case it was the logic board causing the no start issue

Also off topic which version of Mac OS was the first to have color. Running OS 7.1 and its monochrome

Al Kossow
November 8th, 2015, 03:22 PM
Also off topic which version of Mac OS was the first to have color.

The one that shipped with the Mac II. System 4.1 March 2, 1987

Chromedome45
November 8th, 2015, 05:14 PM
That far back? I did not know that thanks. Well now I have some color with 7.1 very odd. But not complaining.

novastar
November 9th, 2015, 07:33 AM
The one that shipped with the Mac II. System 4.1 March 2, 1987

The IIci shipped in 1989 and was discontinued in 1993. The earlier models shipped with 6.0.4, the later with 7.1.1. You will not be able to boot it with 4.1.

Mac OS 7.1 will run in color if available (check the Apple menu). Of course early versions of Mac OS were not very 'colorful'.

olePigeon
November 9th, 2015, 07:45 AM
Was going to post, but yeah, System 6 and up will do 24-bit color. I don't know if System 4 or 5 support 32-bit Color QuickDraw, but you can at least get 4, 16, or 256 colors.

olePigeon
November 9th, 2015, 07:54 AM
I have a IIci at home. It's my main 68k Macintosh. System 7 Pro (aka 7.1.1) is my favorite OS for that machine. It has a relatively small memory footprint and very snappy compared to that of 7.5 and 7.6, but supports nearly all the extra doodads that came with 7.5 and 7.6 through extensions. System 7 was the first OS to be "colorful." :)

Also, the IIci supports up to 128MBs of memory, so you shouldn't need to worry about about RAM. If you want 24-bit color, I'd recommend a Radius PrecisionColor Pro 24X video card. It's (usually) not terribly expensive, and has QuickDraw acceleration. Best video card for your buck at this point. Easy to spot because it's small and bright red.

Chromedome45
November 10th, 2015, 05:44 AM
Ok so is the Radius Pivot any good? Like this: http://www.ebay.com/itm/Vintage-Apple-Macintosh-Radius-Color-Pivot-Display-NuBus-Video-Adapter-Card-/140909394823?hash=item20cedabb87:m:mF-TxHpVJKTFxVsPcNB4OBA

olePigeon
November 10th, 2015, 09:20 AM
Well, it's good if you have a Radius Pivot monitor to go with it. I'd wait for a Radius Precision Color, any model except the 8-bit. In the meantime, just use the onboard video.

Honestly, you won't notice too much of a difference unless the video card has QuickDraw acceleration.

Here's a link to a list of video cards and their features:

http://www.lowendmac.com/video/

You can sort through and quickly find video cards worth buying. I'd recommend one that does at least 800x600 @ 24-bit color with QuickDraw acceleration. Well, at least, that's my minimum standard. :)

Some cards have additional options like DSP daughtercards for Photoshop acceleration, and some like the eMachines Futura LX has a socket so you can add an ethernet card to save you a slot.

ClassicHasClass
November 10th, 2015, 02:12 PM
I remain a fan of the 8*24 GC, but only if you're running 7.1 or earlier. It's my preferred card for the '030 systems and is faster than many accelerated cards, even many of the Radius ones. Unfortunately they were never very common.

olePigeon
November 10th, 2015, 04:40 PM
It's a great card, but not well supported after 7.1. Also a bit pricey if you can find one. Of course, all the good cards are a bit pricy. In case you get lucky, here's a list of what I believe to be the best video cards (I believe that the Villagtronic, Sonnet, and SuperMac are all the same card, just different companies made them with their own software package.):

Radius LeMans GT
Villagetronic MacPicasso 340
Sonnet Crescendo Sonata Pro 24
SuperMac Thunder II GX 1600
Radius Thunder IV GX 1600
RasterOps Horizon 24

Chromedome45
November 12th, 2015, 03:49 AM
So last night the IIci decided it had enough and powered it self down.

I could get it to power on for about a minute afterwards but then it would go out again. So I replaced the other 74HC132 chip at UD13 and C16 the one cap I missed. While attempting to reinsert logic board into the frame I pushed on C16 and broke it off (the Cap) along with most of the Negative side pad. So I soldered a through hole 47uF Tantrum cap in it's place. Ran for a couple of hours and would not startup.

When pushing power switch it just blinked. So I thought I had a short someplace. So my suspect was the C16 cap I installed. Yep it had shorted out! So I removed it and it powered on again. So I thought ok put another through hole 47uF cap in.

Nope when I put that one in no power on. So I completely removed it and it powers on again!

Really weird. So the position of C16 in front of NuBus slot C I guess is to clean up any spikes or noise on that slot? Just wondering why it won't start with that cap in? Any ideas? So I will let it go like that and see what happens.

geoffm3
September 27th, 2017, 10:15 AM
Followup to a VERY old thread. The problems I had with my IIci mentioned earlier in the thread are now fixed as of today. As a shotgun measure I put a brand-new set of tantalum caps on my board and no dice... still had the problem (this was after having recapped several years back with the standard electrolytics. To add to the strange symptoms I experienced, I also noticed that having an external SCSI device plugged in and powered on would prevent the system from turning on at all (in my case a Syquest EZ Drive and a Zip Drive)! So, I started probing around in the startup circuit:

The output of the gate directly from the keyboard switch never changes state regardless of the position of the power button (it is always 0). When the power switch is triggered this should go to 1. In some cases the output of the last gate (pin 6) before Q4 never gets all the way to Vcc, it hovers in the ~4.5-4.8V territory, which is marginal enough for Q4 to switch on, which might explain the system switching on spontaneously... once it's triggered then the normal +5V takes over to keep the system powered on. I've found that the external SCSI device only has an effect when the device is powered on (both the EZ Drive and the Zip drive have the same resultant behavior). There is a diode from the +5V supply to the SCSI port and Floppy ports to prevent feedback to the system from an external device that shows a few tenths of a volt on the +5V supply side when the system is powered off and the SCSI device is on (i.e. I have voltage when the diode is reverse biased since +5V supply rail is effectively GND when powered down). A little strange (depending on the type of diode I suppose) but I don't think that this should have much effect assuming that the HC132 is working normally, so I suspect that the new IC will fix both issues as everything else seems to check out.

.....


It turns out that UE13 was indeed the problem on my board. I replaced with a brand-new HC132 part and everything is working great!