Hi all I desperately need to know if this is normal behaviour for a late 2011 MBP 13". If anybody knows it will be greatly appreciated All a bit of a mystery to me I'm afraid! I have a macbook pro late 2011 13". I believe the battery is a dud (it will not charge at all). Seems to only give 3v out on some pins (this goes to 12.5 on some pins when the power is connected on laptop). To turn it on I must hold down the power button for a period of time and it works (with or without the battery connected). If I let the power button go too soon it will turn off. The machine also turns on and off briefly when you first plug the power connector in. It runs completely fine with the battery unplugged (up times of days+ no crashes & passes a linpack test). However it is only clocked at 700mhz and will not clock any higher... (no speedstep). If I leave the battery in then the machine will turn itself off after a random period of time. It is still only clocked at 700 mhz with the battery in & the kernel uses all of the CPU in Mac os (but this is not an issue in windows?). Any ideas?? Is this simply because there is no battery in the machine or is there something wrong with the charging circuit/SMC? If this is normal - I will buy a new battery! If not, any ideas how to fix it? Many thanks in advance! Really struggling to understand this behaviour.