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Kokujin
June 8th, 2005, 03:22
I bought it used and i have had for about 9 months now and it has always worked fine.Today it shut off on me, i turned it back on without a disc in it and it stayed on, but when i put a disc it, it starts to spin then shuts off.If anybody know whats wrong with it please help.

ptr.exe
June 8th, 2005, 11:56
Sounds like a problem with the PSU, have you tried cleaning the six pins that connect the power board to the main board? obviously don't do this while its turned on :p

Its very likely its that, as it happens to alot of DC's, just make sure theres a good connection between the pins and the PSU.

Kokujin
June 9th, 2005, 01:26
I tried it and it still turns off when the disc tries to play. Thanks though.

Dreambox
June 9th, 2005, 02:05
Try this it should work for ya. http://www94.pair.com/jsoper/dc_fix.html

Kokujin
June 9th, 2005, 07:41
I tried this already.The problem I am having is that i turn it on without a disc in it, and it will stay on,but when I place a disc in and it begins to spin ,it shuts off.Only in the instance of it having to spin the disc it shuts off completely(not back to the menu).Thanks for the help though.

ptr.exe
June 9th, 2005, 13:16
Could be a faulty spindle motor, someone on dcemulation.com had this problem, it's rare but can cause the DC to reset when it cant read the disc.

Test the spindle motor (motor that makes the disc spin) just remove it from the GD-ROM assembly and test it with some batteries, make sure it can spin both ways and does not make a grinding noise.
This is unlikely to be the problem but has happened to people in the past.

Do you have access to another DC? if so you can swap the GD rom assembly to see if the problem persists, if it does its the PSU if not then its the GD-ROM, this will narrow down the possibilities of what the problem is.

Dreambox
June 9th, 2005, 16:02
that is a weird problem, well good luck i hope you fix it i have had to problem of this sort yet sorry.

Kokujin
June 9th, 2005, 22:25
Good news. I found out whats wrong with my DC, bad news its extremely hard to repair it seems the GD-ROM controller board blew a capacitor. when the DC detects a blown capacitor, the safety mechanism automatically shuts off the DC.
Unfornuately, there is no way to fix this. unless I can find the same exact capacitor, remove the blown one, and solder in the new one. Thanks everyone that help it was really appreciated.

fackue
June 10th, 2005, 00:43
What does the capacitor look like, and where is it located? Maybe even a picture, so it can help others with the same problem.

Kokujin
June 10th, 2005, 03:46
Thats the thing someone told me this at DCforums and I have no clue where the capacitor is located or even what kind it is.

fackue
June 10th, 2005, 03:55
You have a link?

Kokujin
June 10th, 2005, 05:23
Yeah here http://dcforums.net/index.php?showtopic=22712

ptr.exe
June 11th, 2005, 14:57
You may be lucky if the blown cap has actual visual signs of being blown, ie balck marks around base. Take a look, its not as bad as my DC main board has a blown cap somewhere which stops any visual signals, ive been trying to find it for ages but there are too many.

NeoGohan
November 21st, 2005, 13:29
Did anyone ever find a resolution to this problem? I'm a few months late from the last post lol. My Dreamcast has been like this for the past 2 years and was never able to figure out what was wrong. :( Please inform me if you found a way to fix it.

semicolo
November 21st, 2005, 18:59
I don't think the dreamcast could be able to detect if a condensator is blown, more likely when the motor starts it drains too much current and the psu shuts off. Did you measure the voltages of the psu ?

NeoGohan
November 22nd, 2005, 00:46
I haven't measured the voltages of the psu, but I took out the psu and placed it in a working dreamcast(i took out the working dreamcast's psu, of course) and it runs fine. I haven't tried swapping out the gd-rom units yet. But I'll get to that in a little bit.

UPDATE:
Just swapped the gd-rom drives. Took the good dreamcast's gd-rom unit and placed it in the old dreamcast. Turned it on, and voila~ It runs great. So, I guess the gd-rom unit is dying or something. But I still havent figured out what caused the gd-rom unit to go bad. Anything I should check? I'm not that very knowledgeable with electronics. :X

semicolo
November 22nd, 2005, 18:53
maybe there's some mechanical problem preventing the motors to spin, if so it'll call for a lot of current ant it could trigger an auto shutdown.
So check if nothing's jammed.

ptr.exe
November 23rd, 2005, 15:27
I don't think the dreamcast could be able to detect if a condensator is blown, more likely when the motor starts it drains too much current and the psu shuts off. Did you measure the voltages of the psu ?
The DC wouldnt 'detect' it as such, but it wouldnt work correctly, it could be the cause of a problem.

The most likely thing is the GD-ROM board is fried, or the spindle motor is dead. You could try replacing the motor but it is really annoying getting it in at the exact same angle for the laser to not skip (take longer to load).

NeoGohan
November 23rd, 2005, 22:03
Played with it some more with the lid off.

I start it up with "lid open."
It goes to the system menu.
I close the lid by pressing the black switch in the back, no cd inside.
The motor spins and the laser moves its eye sticks its eye out and back down 3 times. The motor stops spinning after this.
This should be expected I think. This seems like motor is ok, and laser is ok. But not sure, wanted to ask you guys.

While the power is still on, I let go of the black switch to close the lid.
I put a CD in and press the black switch. It spins a quarter turn and stops.
The laser didn't move at all.
This, I didn't expect, I expected it to turn off like it normally would. But it seems like it doesn't even bother to read the cd, and it barely tries to spin the cd when the lid is closed.

Seems like the everytime the laser is trying to read a CD(it seems to be able to read fine without a cd in it), it shuts off the power. Circuit problem?

What do you guys think? Nothing seems to be stuck on the gd-rom unit. I also played with the laser calibration, but that didnt seem to do anything.

Thanks for your input, guys.

burhancik3
March 10th, 2007, 23:32
ouihpokjl

naruto179
June 23rd, 2007, 19:01
Rather old thread, but I am having a similar problem with a Dreamcast I bought at a thrift store. When the GD-Rom is in the system, the red power light flickers on really quick and then off. When I take out the GR-Rom drive, the system powers on with the Dreamcast start up screen and then freezes, so I know the system at least has power. When I swapped the GD-Rom drive into a working Dreamcast, I experienced the same thing, so I know it's something faulty with the GD-Rom drive itself. Any ideas of how to bring it back to life?