Won't start up with any battery installed
This BlackBook 2,1 had some cranberry juice spilled on it (of course the owner said "not very much", that's what they always say!) and the next day would not start up.
I took off the top case and could see no sign of liquid. Stuck another top case on and it booted OK after resetting SMC and PRAM (this was with AC power, no battery installed, before I replaced all the screws.) Put the original top case on and it booted too, so I buttoned it up. Noticed the magsafe light was green even though battery showed no charge when battery button was pressed. After reassembly, computer showed no sign of life when power button pressed. Removed battery--starts up fine on AC. Noticed slight flickering on magsafe light with battery in (not the stead blinking you get sometimes with other problems.)
Installed a new battery from another MacBook--white, but battery is same model, A1185, and identical power specs. Now the magsafe light blinks green (as opposed to flickering! No booting. Reset SMC; now the magsafe light does not come on at all. Remove the white battery, and we boot up fine.
Later note: Noticed a faint clicking when power button held down (with battery in.) Must have held power button long enough to do a firmware or programmer's reset, because it booted! But with fans going full blast. Shut down and started again, and it worked, again with full fans. Another SMC reset made it revert to previous behavior of not starting, though this time with no clicking when power button is held down. Removing battery enables it to boot on AC power.
The owner says it was working on battery before. Could the juice have damaged the power system somehow? Anyone know what it takes to fix this? Or is it now a desktop computer? Could a replacement top case help in a power situation like this?