Hi all,

I just got an IJ pinball machine today. Because i wanted to put it in my attic i had to remove the backbox to get it up the stairs. This meant disconnecting all circuit board connectors. I labelled all connectors and after i got the machine upstairs i reconnected everything carefully. When i powered on the machine the DMD did not give a normal response. Video of the startup of the machine:

Can anyone give me a in hint as to what might be wrong?

Thanks,
Bart

Thank you for your suggestions.

I checked all connectors, checked the right position and the right direction of all connectors. This all seems to be fine.
Also checked the ribbon cables, these are connected properly.
And yes, i put the ground strap back on.

What can cause the DMD to malfunction on startup?

Rechecked the ribbon cables but they are definitely in the right position. The red stripes are pin one and they are connected exactly as they were before i started disconnecting everything (checked the picture i took before disconnecting).
One of the cables could be a bad one but this seems unlikely because everything was working this morning and i handled everything carefully.

Any other ideas?

DSC01811(1).JPG

I uplugged the ribbon connector from the DMD board and then powered it on. It does exactly the same except the DMD has 4 pixels lighted up instead of many random pixels.

@system11, i must have misunderstood you earlier because then i only disconnected one of the DMD board ribbon cables. I now disconnected all three and then the machine boots. Everything works except the DMD (obviously), flippers and sound. Does that give a hint? Is there maybe something wrong with the CPU->Fliptronics->Sound->DMD ribbon cable?

@Borygard, if i disconnect all ribbon cables from the CPU board the diagnostics LED (D20) starts blinking. I checked all the header pins but they seem fine to me.

If one of the ribbon cables is causing this problem i might be able to get new ones today.

I'll try to connect all ribbon cables one at a time, but i don't really know what to look for...
Also, i noticed that LED 3 on the power driver board lights up when i start the machine although the operations manual says it should be off during operation. Does anyone know what this means?

IJ_LED_list.png

Thank you for all your help everyone, yesterday i switched the ends of the DMD board->CPU board and DMD board->DMD ribbon cables and this solved the problem!

I'm still replacing my ribbon cables with new ones this weekend, they work now but they are just old. A complete set of new ones costs around $30 here. Maybe that would solve your problem as well.