latest macbook problem

[brendan67]

hi

new hard drive just fitted after crash, now the macbook shuts down
as soon as it reaches reserve battery power.

don't tell me its going back to apple, anyone got any suggestions of how
to solve this?

regards

 

[dekan]

hm.. maybe the power management is a bit messed up? what setting do you use?

also: you can go to: /Library/Preferences/SystemConfiguration and delete the PowerManagement.plist
it will be created again once you change settings for your power management

hope that helps

 

[cwa107]

Once it gets to reserve power, the power management system will determine when there is not enough power to continue to use the system in a stable manner and forcibly sleep the system. This is completely normal behavior. If you'd like to reset the power management system, reset your PRAM by powering the system off, power it back on and press and hold Command-Option-P-R. Wait for the system to chime 3 times and then release.

 

[brendan67]

macbook

hi guys

thanks yes i'll try all you suggest

cwa107

can't be normal to shut down completely - just because
you are in reserve power - surely

i lost stuff i was writing at the time and it did not behave this way before?

regards

 

[Zoolook]

Once it gets to reserve power, the power management system will determine when there is not enough power to continue to use the system in a stable manner and forcibly sleep the system. This is completely normal behavior. If you'd like to reset the power management system, reset your PRAM by powering the system off, power it back on and press and hold Command-Option-P-R. Wait for the system to chime 3 times and then release.

I see a few people recommending this, but they're all wrong because it's not how you reset the PMU. PRAM has nothing to do with power management.

PRAM contains these:

Status of AppleTalk
Serial Port Configuration and Port definition
Alarm clock setting
Application font
Serial printer location
Autokey rate
Autokey delay
Speaker volume
Attention (beep) sound
Double-click time
Caret blink time (insertion point rate)
Mouse scaling (mouse speed)
Startup disk
Menu blink count
Monitor depth
32-bit addressing
Virtual memory
RAM disk
Disk cache

No mention of power management there...!

PMU is reset like this:

MacBook, MacBook Pro

If the computer is on, turn it off.
- Disconnect the AC Adapter and remove the computer's battery.
- Press and hold down the power button for 5 seconds and then release the button.
- Reconnect the battery and AC Adapter.
- Press the Power button to restart the computer.

Now if the power management unit really is messed up, after doing this, you'll see that the amount of power remaining has possibly changed.

 

[cwa107]

I see a few people recommending this, but they're all wrong because it's not how you reset the PMU. PRAM has nothing to do with power management.

Noted. Thanks.

 

[cwa107]

hi guys

thanks yes i'll try all you suggest

cwa107

can't be normal to shut down completely - just because
you are in reserve power - surely

i lost stuff i was writing at the time and it did not behave this way before?

regards

You are correct, it should not just shut down - but it will sleep if there is not enough power to reliably sustain the machine.

 

[brendan67]

macbook

hi

well, i've reset the pmu, and problem has gone!

thanks guys

regards

 

[Zoolook]

hi

well, i've reset the pmu, and problem has gone!

thanks guys

regards

You're welcome, it's nice to know when advice was useful.