17-inch Mid-2009 MBP Barely Turns On Anymore

Hi Everyone,

I'm having an issue with my mid-2009 17" MBP that has been progressively getting worse over the past few months. When I first noticed this problem I was noticing that my computer was not turning back on from sleep. I would open the lid and I would get nothing. The only way to get it to come back on was to hard force it off by holding the power button and then restarting it. Interestingly this only happened though if the computer was sitting long enough in standby (>1hr). If the computer was put in standby and I came back to it a half hour later it would come right back on without issue.

As time went on, it eventually got to the point where pressing the power button once was no longer turning it on anymore. I would have to press the power button about 3+ times before it turned on. As the issue progressed further, I would have to press the power button 15-20 times before it would turn on. After a couple more weeks a new issue started: instability. After getting the computer to turn on (which up until this point when I got it to turn on it stayed on and functioned fine), it would last for about 3 min then completely shut off, so again the power button pressing begins. Next time it would last maybe 7 minutes, and then finally on the 3rd time it would become stable and not turn off again (and the computer continued to function perfectly while it was running). So today I'm at the point where I consider myself lucky I even have the computer on now as I type this, as I must have pressed the power button 750+ times (seriously) in effort just to just get it to turn on. I actually thought earlier today the computer was finally gone.

I'll do my best to explain what happens when I press the power button: When I press it, I briefly see the white power light turn on and then shut off instantly. I can hear the fans in the computer begin to spin up (which can be visually confirmed), but immediately shut off. No picture, nothing. This is basically what happens about 97% of the time. The other 3% is that I get the computer to turn on (white screen actually shows up), but it doesn't even get to displaying the Apple logo before it shuts off. I get no beeping so I can't even an error code out of it, and no power light consecutive flashing either.

My computer has gone through some upgrades/replacements over the years, but I don't think that's related to this issue. The only mods done to this computer are an upgraded Seagate 750GB 7200rpm HDD (came with a 500GB), and I have upgraded the ram to 8GB (Crucial) from the 4GB it came with. I have tested the RAM in another computer so I know it works fine, and I'm pretty sure I would get an error code if it didn't. Otherwise I have done no other modifications to the computer. Also as a note, my battery is in need of service (so it says), so maybe that could be related? If I connect the AC adapter I still have the same trouble so I kind'a doubt that but I don't have much experience with this issue.

So, does anyone know any tips or tricks that I can use to try and revive this thing? I'm way past my 3-year protection plan so warranty is out of the question at this point. My personal hunch is something related to the power supply on the motherboard is no longer functioning properly. I really hope I'm not screwed here but I got a bad feeling about this...

Many thanks,

Alex