Chosen Solution
So, Macbook Pro 2009, 3.06ghz, duo 8gb, 17" Not turning on when new battery in, or out, power board seems to be working, does the same with old battery still with some juice in it. If I keep trying over and over it comes on and stays on until I try a restart or shutdown, sleeps fine…. HELP! Update (10/25/2016) OK so I have put my old Battery Back in its at “Replace Soon” so should be OK. Fans seem to be going a little fast and all the time. So the new battery, really not making much difference there. So once I get it started, its all good, not sutting down. So what is it? Something to do with starting up? Help!
Connect the power adapter to the Mac. On the MacBook / Pro’s keyboard, hold down the Shift+Control+Option keys and the Power button at the same time. Release all keys and the power button at the same time – the little light on the MagSafe adapter may change colors briefly to indicate the SMC has reset.
Here’s link to the Apple Support document that talks about what @mayer suggests. Reset the System Management Controller (SMC) on your Mac
