Okay, here's a tricky one for everyone. I have a Dell Studio 1555 with a power issue. Originally when we bought it, the lcd back cover was broken, which is where the power button is located (if you look at it open, it's on the right hand side as part of the hinge). So, we ordered a new back cover with power button and installed it. Everything seemed to be working fine but now we have a problem.
If the laptop SITS for a while, not plugged in, it will not turn on when you press the power button. If you plug it in, it does not turn on. However, if you take the battery out, hold down the power button for 10 seconds, then plug in the AC Adapter, it turns on! You can turn it right back off, put the battery in, unplug the AC Adapter, and it will still turn on just fine.
Tried this several times. Once it is 'working', you can turn it off and back on running just off the battery. I've checked the CMOS battery to see if it was undervoltaged, which it was not. I'm frankly out of ideas. It seems like the power isn't dissipating from the motherboard properly. As you can imagine, I feel like pulling my hair out. I wouldn't mind it except I'm a computer shop and I wish to sell this. I can't tell the customer to go through all this just to turn it on. Any ideas?