Double Dragon edge connector problem

GoneMad

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I've been wondering why my double dragon is not booting up. So normally you start with the voltage. Everything seems OK at the PS so I get a couple pinout sheets of the net, both are the same so I grab my multimeter and start to check voltage at the edge connector. Pin 1 and 2 both ground. And so on.. then I get to pin 6 to check the +12v and,,hold on a sec, there is no wire on pin 6! There is on the solder side but not the part side. If the schematic shows +12v should be on pin 6 of both solder and part side, there should be, right? Noticed a couple other wires a little mixed as well.
 
the 12v is for the audio circuit i believe
should still boot wether its there or not

test your voltages ON THE GAME BOARD or PCB (Printed Circuit Board)
make sure your ground probe or the black one is connected to the logic ground (pin 1) and not on the earth ground or screwy readings can be seen

the +5 volts should be at +5.1. there is the +5v rail on the PCB that goes to a lot of chips. just follow the +5 volts where it comes onto the PCB and sometimes theres a capacitor you can easily test for the +5v on. sometimes theres a test point TP1 or TP2 you can test for also
 
Yes - 12V is ONLY for the audio amp, the game will boot quite happily without it, you will just get no sound. Also the -5v is only used by the audio system too, no -5v gets you no music, the game will boot with just the 5V connected. You have another issue.
 
OK, thanks for the replies. It must have been setup for now sound because the speaker wires have been cut midway and nothing on the harness. But to have it operate fully functional, with sound, I should have all these hooked to the edge connector where they should be. I do have a spare board coming for this.
 
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