powering head unit outside vehicle wires?

I have a Pioneer DEH - P7500MP that has been in my pickup for at least 5 years. About 2 months ago a CD became stuck inside of it. When I try to eject it gives me an error..Can't remember the specific error at the moment. I have pulled the unit out, and I have a 12 volt power supply. I was going to hook the power supply up to it and try to see if I can figure out what has the CD stuck. What wires do I need to use? I tried hooking ground to ground and hot to the yellow battery wire and got nothing. I also tried hooking the hot wire from the PS to the ACC, and still nothing. Should I comibine the two together? Also, Could it be that the unit is looking for 13 or 14 volts vs 12? Thanks

Twist the Yellow and Red together for 12v(positive terminal). Black to ground and you are on your way...M.E.C.P & First-Class

Go slow and drink lots of water...Procrastinators' Unite...Tomorrow!

I have done that..But I'm still getting nothing. My power supply is a variable 1.5-12v 300 mA. I think it just may not be putting out enough juice to fire the radio up. The radio was working fine when I pulled it out yesterday. Not getting enough power is the only thing I can think of.

I know for a fact that the radio works fine. It was in truck just yesterday and I was listening to it. The cd player has just been stuck for some time. I dont have my truck nearby or a battery. I just grabbed this power supply thinking it would work. I read somewhere else that they require 12v 5A. This PS is putting out only 300mA..maybe thats the issue.

300mA isn't enough - that's only 4W.

As stated earlier, a 300ma supply is not even close to being large enough to turn that unit on. Walk it outside to your vehicle and use the battery.