Need help with G5 Power issues please Model A1047

i just acquired the same model powermac and i have the same issue... i would also like help, although im afraid that both of us are suffering from a failed logic board..

 

Doubt it will be the motherboard, I have just had a Power mac in at the office. with the same problem. I dismantled and checked the power supply no signs of bulging capacitors or any internal damage with the power supply.

I have a college that has a working powermac i grabbed his psu out of his and put it in the customers and it fired up straight a way.

if your game enough, strip it down, you will need to remove both cpu's the front fans / back fans ( make sure u label the cpus according to there position top / bottom) remove the 4 screws under the case psu should come up, may need some force to get it out so be careful.

 

I have a good 600w PSU laying around that you can use to test yours if you think you can change it yourself. If you're near Cleveland, I'd do it for free for you. I also have service manual if you need it.

 

it is either the psu or the ram, i believe

 

RAM you can for sure exclude of your "suspicions list".
It looks like PSU (from described symptoms), I bet on its capacitors. If unit was unused for a long time, they could simply dry-out. It happens sometimes, especially with "not best quality" capacitors.

 

Sounds exactly like what happened with the 1.6GHz Powermac G5 I had a couple years ago. I made this YouTube video showing the problem. Watch it, and see if your problem is the same. I replaced my PSU and it didn't fix the problem. To this day I'm not totally sure what was wrong with it, but I am almost 100% sure it was the logicboard.

 

battery?

If it was unplugged for a while, it may be the battery - it's a 3.6 volt Lithium battery.

Mine was like that (same model, same problem), didn't get a chime or anything until I replaced the battery. (full disclosure, my machine is still not working, but at least it chimes before it hangs on startup)

 

Could you send me the service manual

If it is in PDF that would be great if not where could I get a copy?