Dreamcast Black Screen - No Audio or Video

[thegonzo]

Hi all,

I have a PAL early model Sega Dreamcast, which is unfortunately broke.

Symptoms: Black screen, no audio or video.

Troubleshooting: Tested on 2x televisions and computer monitor with AV in. Replaced CMOS battery.

Can anybody assist or point me in the right direction? I have a feeling I need to investigate AV output connector, but not sure where to start.

I am handy with tools and soldering.


Cheers!

[Ian Micheal]

And your sure the av cable is working had many that dont.. does the light come on the dreamcast if you put a game in can you hear it reading it.. not very common to be dead with no video or audio..

Does the power light led come on? put a game see if it reading it for one.. might have a bad av cable or common not push in all the way because of a bent pin or crap

[thegonzo]

Hi Ian,

Yeah light comes on, game spins up, VMU beeps *and remains feint grey*.

I have not yet tried a different cable, but am a bit doubtful that could be it as they're not common to break..

Have opened up the unit before and given it a clean out using a cloth and recently compressed air spray.

[thegonzo]

Hi guys,

I've performed further testing lastnight and here is a clarification of symptoms:
-Device powers on, orange light on, can hear the device working albeit quite loud.
-VMU connected to the controller chimes at launch and when reconnecting the controller to port.
-VMU does not display anything subsequently, remains a faint grey screen.
-Have tried to navigate blindly with a game inside the unit, pressing <- and A (initial date/time setup), but VMU still lacks output.
-Game disk spins, as noticeable when opening lid.

I am guessing this could be a mobo or PSU fault? If the prior, is it worth fixing?

Recently procured a multimeter from JayCar, happy to test any circuitry if I can be provided with guidance?

Appreciate any suggestions

[Hakai]

Hi, know this is an old thread but did you ever figure this out? I have roughly same issue. mine starts up, shows the DC logo & then just a black screen.

Thanks.

[CARROMATO]

Firsth rule out AV cable is the problem.

Then
The Most frecuent is a GD DRIVE dead. If you keep a wahile yu can see the dremcast logo in the screen.

Other frecuent problem is the Dremcast video encoder chip. If you have basic solderin knowlege can change it.
you can buy it on aliexpress or ebay etc.

[SMiTH]

you might find that you used the wrong screws on the back of the dc where the video port is.
if you used the longer screws they will make contact to the board.
try removing all the screws found in the back of the dc, then test.

[CARROMATO]

you might find that you used the wrong screws on the back of the dc where the video port is.
if you used the longer screws they will make contact to the board.
try removing all the screws found in the back of the dc, then test.

Yes forgot this other posibility. !!!
A lot of dreamcast dead by this way. !!!!

[Hakai]

It was the fan. some how the fan had partially disconnected. for some reason the dc kept cutting to a black screen but once the fan was connected it worked fine. I turned dc on put alone in the dark on & it worked for over 4hours. I also played ReZ for a few hours, no issues at all.

Thanks for the replies though.

[Ian Micheal]

It was the fan. some how the fan had partially disconnected. for some reason the dc kept cutting to a black screen but once the fan was connected it worked fine. I turned dc on put alone in the dark on & it worked for over 4hours. I also played ReZ for a few hours, no issues at all.

Thanks for the replies though.

Yeah what i thought it was and said it the fan seen it many times.
if you get a black screen and every thing else working then it stops
most times it's the fan.. if it's not spinning the dreamcast will not work