Dreamcast - Controller boards fuse blows repeatedly

[chôkai]

Hello,

I recently received a defective Dreamcast (VA0) where the controllers were not recognized. Checked the controller board and fuse was blown, replaced and then tested again. Controller was still not recognized, rechecked and fuse was blown once again.

For testing I replaced the complete controller board incl. ribbon cable and the fuse was also blown... I can rule out the controller, because it works fine on other Dreamcasts. So it seems that something on the motherboard, causes the fuse to blow ...

Has anyone here ever had the same problem or could tell what I should check on the motherboard ?

Any help would be appreciated

[djhazardous]

You're not plugging and unplugging the controllers while the Dreamcast is on, are you? As that is known to blow fuses.

Check that the ribbon cable is seated properly in the motherboard and the controller board, sometimes it needs an extra push. Since you already tried a controller board from another Dreamcast you can rule out the controller board being the culprit.

Other than that I have no idea and would also lean toward it being an issue on the motherboard. Maybe it has a blown capacitor somewhere?

[chôkai]

Interesting, I did not know that plugging in a controller while the Dreamcast is on, blows the fuse....

Anyway, in my test the controller was already plugged in. Had tested it several times and also cleaned the connector for the ribbon cable with isopropanol.

I had already looked at the motherboard, by visual inspection I could not see any burst or burnt caps