Macbook Pro will not power on without battery installed
I have a Macbook Pro A1226 that fails to power on without a battery installed.
i.e. will not run off AC power on its own. I have tried 2 other power adapters, no change. All 3 adapters are outputting the correct voltage without fluctuations.
But, if I am in OSX with a battery plugged in, shutdown the laptop, remove the battery while AC is still plugged in, it will power back on without any issues. But as soon as I remove the battery, it will not power back on using just AC.
Is this an I/O board issue, or a mainboard?
I have power drained the unit and reset the parameter ram.
Thanks
a1226, Mac OS X (10.5)