Amiga.org

Amiga computer related discussion => Amiga Hardware Issues and discussion => Topic started by: marcfrick2112 on September 13, 2006, 04:40:03 AM

Title: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: marcfrick2112 on September 13, 2006, 04:40:03 AM
Hello, Hope someone could help me....Had a power failure
for about 25min. today. When power came back on, I found my PC
and my Amiga 4000/040 dead. The PC just blew its PSU, I could give a rat's
butt about it  now...

The 4000 won't boot, won't even try to boot a floppy. I can
hear the HD spin up (clicking) but only get a screen flash
then a yellow screen. I know this is CPU exception and/or
hardware failure.... Anyone have this happen? Any ideas what to
check? I need to try to fix this myself, as I don't have the
cash to send it to, say Amiga Center in France. As luck would have
it, I got laid off from work 2 months ago....:(

Worst part: both the A4000 and IBM had surge supressors....

Any ideas?

Marc
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: zombi on September 13, 2006, 05:49:18 AM
:-(
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: countzero on September 13, 2006, 06:15:00 AM
well first you should calm down, then check if the cpu card is properly seated. then I would check the psu lines if proper voltage is coming.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: zombi on September 13, 2006, 06:19:07 AM
There should be a fuse in somewhere.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: marcfrick2112 on September 13, 2006, 08:22:46 AM
Thanks everyone,

@countzero: OK, will try to calm down...I'll check the CPU
card, but I can't see how that could be problem, the A4000
was working several hours before the power failure, surely
that couldn't have made the cpu card come loose??

@zombi and countzero: Any idea where this fuse is? In the
PSU maybe? I hope so, the PSU on my IBM-compatible had NO fuse.



Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: zombi on September 13, 2006, 08:34:18 AM
ATX PSU's, i mean cheap ones, have no fuse. They have only a stupid capasitor thingy to cutoff current when there is a short-circuit.

I don't have any idea where the fuse in A4000 either it can be on mobo, somewhere near power jack, or on PSU. But there shuld be one in somewhere!  
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: Astral on September 13, 2006, 08:54:43 AM
I had a similar problem after a power failure, where my A4000 would come up with a yellow screen, the power light would flash, and the hard drive sounded like it was trying to boot. I thought that something was likely to be damaged. However, after reseating all the RAM chips all was fine. I know it sounds odd, and that the two do not seem related, but it fixed my A4000...
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: Quixote on September 13, 2006, 11:10:21 AM
:-? Hmm, I'll have to try that, too.  My own A4000 stopped workinging a while back, but I've never gotten it working again.  (But only because I never seem to have time to get around to it....)
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: chiark on September 13, 2006, 11:14:37 PM
ground yourself
reseat all the chips
cross fingers

Yellow is general CPU exception before bootstrap loaded, so I'd look suspiciously at the kickstart chips, memory chips and processor board.  In fact, every connection :D
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: pierre on September 14, 2006, 12:25:05 AM
yeah calm is the bast way to fix this type of thing.
Yes, it was working just fine a minute ago, but something came loose and once you open her up and firmly and nicely tighen her back up she will be back with you in not time.  This happpend to my 4k until I rebuild her...btw that something you will end up doing one or twice a year bepending on how it goes.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: Tomas on September 14, 2006, 01:41:56 AM
 :-( That sounds really bad... Sounds like you had some power surge. Odd that the surge protector did not help.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: marcfrick2112 on September 14, 2006, 04:22:14 AM
Hi eveyone, thanks for all your advice,...I re-seated all chips,
cables, ROMs, processor board (twice) Still a no-go...

I will have to send it to a repair guy in KS (USA)

Think it may be a mobo problem :(

Again, thanks everyone...
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: bertambala on September 14, 2006, 05:41:20 AM
If you don't mind me asking, who is the repairman in Kansas?  I live in Colorado, so that might be useful to know. Thanks....
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: motorollin on September 14, 2006, 07:02:16 AM
Did you check the voltages coming from the PSU?

--
moto
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: marcfrick2112 on September 15, 2006, 06:30:14 AM
@moto: Yeah, I checked the voltages coming from the PSU with a multimeter, everything was fine [shrug]

Regarding ther reapir guy in KS, his name is Ed Jeffries, runs  a place called Video Lab, seems very good (Ibought an A1200 desktop from him couple of years back..) Number is 913-403-0045
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: motorollin on September 15, 2006, 06:49:13 AM
:-( Keep us up to date!

--
moto
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: alexh on September 15, 2006, 08:19:25 AM
http://it.aminet.net/hard/misc/errormessages.txt

Yellow on boot is noted as a strange error (12 on this list) but I used to get it all the time on my A600 if the Trap Door Chip RAM expansion had come loose.

Do you have any spare 30-pin simms?

Swap out the 30-pin simm that is the chip RAM one.

----------------------------------------------------

If you get yellow on power up, I believe that 90% of the Amiga is working.

The Amiga uses the 68k CPU to run POST. This means your CPU is working.

It uses the kickstart ROM to load the test routine that runs. It also CRC's it and this means your kickstart ROM is intact. (Or you would have a RED screen)

It uses registers in the Lisa chip to change the screen yellow etc.

Check your onboard battery, acid corrosion of the tracks near the SIMM sockets I imagine that can be responsible for yellow screens.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: marcfrick2112 on September 16, 2006, 12:26:00 AM
alexh: well, I don't have a spare 30-pin SIMM to try (that I can find)...I have 72-pins coming out of my ears...

Checked the battery, looks fine, and there is no corrosion that I can see....

Well, I haven't sent it off for repair yet, so I'll scrounge for a 30-pin SIMM...does it have to be 2MB to work?
 
Am grateful for all the ideas.
OK, my dad (also big-time Amiga fan) wants to get a spare 4000
The above-mentioned Ed Jeffries has a 4000 with a 40Mhz '040 WarpEngine, SCSI, 2GB HD, and CD-rom for $500.00, supposedly completley refurbished, you guys think I should go for it?

Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: bertambala on September 16, 2006, 06:11:48 AM
marcfrick2112:  Thanks much!
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: alexh on September 16, 2006, 11:46:28 AM
£280 for that specification A4000 isnt too bad.

If it has KS3.1 and some extra Fast RAM on the accelerator and a BUSTER revision 11 then go for it.

Shame it doesnt have a graphics card or a network card but you could always get those later.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: Ilwrath on September 16, 2006, 11:59:18 AM
Quote
alexh: well, I don't have a spare 30-pin SIMM to try (that I can find)...I have 72-pins coming out of my ears...


The Chip RAM is a 72 pin SIMM.  And, yes, it does need to be a 2MB, single sided.

And, as far as I know, the A4000 has no fuses at all, and not much to reseat other than processor card and RAM.  Possibly also SuperBuster, if you've had yours upgraded.  Pretty much everything else is surface mounted, for maximum pain in the arse when things go bad.  :-(
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: alexh on September 16, 2006, 04:53:40 PM
My mistake. They are 72-pin. Might be worth trying any you have lying around.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: pedro7 on September 17, 2006, 12:21:09 AM
Quote
Ilwrath wrote:
The Chip RAM is a 72 pin SIMM.  And, yes, it does need to be a 2MB, single sided.

It doesn't need to be single sided, the one in my a4000 is double sided.
Title: Re: Help! Had Power Failure, now A400 won't boot...yellow screen
Post by: marcfrick2112 on September 18, 2006, 02:13:47 AM
Hi Everyone, well, I dont have a 2MB SIMM lying around, I may just
have to send it in to be repaired, thanks for everyone's help.

@alexh: The 4000 I am buying is a KS3.1/OS3.1 machine with
a total of 64MB RAM, and comes with Scala InfoChannel, so
I am going for it!