Agfdhyk

I have had a new battery in my mid 2012 15" macbook pro running 10.11.6

The battery health as monitored through a battery health app downloaded from the mac app store has been deteriorating ever since i installed it and after about 3 months the battery is saying "Service Battery"

This doesn't tell the full picture though, as if it use my Mac once i get the "low battery 9 minutes remaining" warning, it will go on for hours without cutting out.

Ive been told i need to do an SMC reset to address the issue, but each time i do it following Apples guides for laptops with a removable battery, it dosnt fix anything?

How can I know that an SMC reset has taken place, can it be seen in the logs ? Or can i do an SMC reset through some kind of GUI tool which will give me feedback instead of the standard way which i cant be sure has worked.

Here is an output from About this mac > System Info > Power

Model Information:

  Serial Number:    REDACTED

  Manufacturer: SMP

  Device Name:  REDACTED

  Pack Lot Code:    0

  PCB Lot Code: 0

  Firmware Version: 2

  Hardware Revision:    00aa

  Cell Revision:    2

  Charge Information:

  Charge Remaining (mAh):   220

  Fully Charged:    No

  Charging: No

  Full Charge Capacity (mAh):   3918

  Health Information:

  Cycle Count:  81

  Condition:    Service Battery

  Battery Installed:    Yes

  Amperage (mA):    -1943

  Voltage (mV): 10877



System Power Settings:



  AC Power:

  System Sleep Timer (Minutes): 3

  Disk Sleep Timer (Minutes):   0

  Display Sleep Timer (Minutes):    3

  Wake on AC Change:    No

  Wake on Clamshell Open:   Yes

  Wake on LAN:  Yes

  AutoPowerOff Delay:   14400

  AutoPowerOff Enabled: 1

  Display Sleep Uses Dim:   Yes

  GPUSwitch:    2

  Hibernate Mode:   3

  PrioritizeNetworkReachabilityOverSleep:   0

  Standby Delay:    4200

  Standby Enabled:  0

  Battery Power:

  System Sleep Timer (Minutes): 10

  Disk Sleep Timer (Minutes):   0

  Display Sleep Timer (Minutes):    2

  Wake on AC Change:    No

  Wake on Clamshell Open:   Yes

  AutoPowerOff Delay:   14400

  AutoPowerOff Enabled: 1

  Current Power Source: Yes

  Display Sleep Uses Dim:   Yes

  GPUSwitch:    2

  Hibernate Mode:   3

  Reduce Brightness:    Yes

  Standby Delay:    4200

  Standby Enabled:  0

Here is an output from the command system_profiler SPPowerDataType | grep -i "charge information" -A 10

Charge Information:

          Charge Remaining (mAh): 234

          Fully Charged: No

          Charging: No

          Full Charge Capacity (mAh): 3918

      Health Information:

          Cycle Count: 81

          Condition: Service Battery

      Battery Installed: Yes

      Amperage (mA): -2579

      Voltage (mV): 10890

It's quite possible you have a defective battery, bad cable or power handling chip issue on the logic board itself. From the output you posted, here's what we know.

• 81 cycles and FCC of 3918 mAh is way out of specification


• The Voltage and charge measurement that you have 234 mAh (mili-amp hours) remaining


• It's showing a draw of approximately 2.5A (battery is being drained)

The SMC can only accumulate how much battery capacity is left by measuring the current power against the current draw and known full capacity. In this case, it's measuring that you're out of power and indicating your battery needs to be serviced.

There's no "dipstick" that can give you the actual charge, the SMC must calculate it and from the data it's getting from the battery, it thinks it's failing even though it continues to work.

Your best bet is to replace the battery (it's probably still under warranty) and still more likely to be the cause if you were careful with the cables and reseated them.

Reviewing your Battery report:

Considering you installed it as "new" 3 months ago, unfortunately it behaves as 3- 5 Years old.

The Full Charge Capacity (mAh) value is down to 3918 (<50%) !! which is the absolute indicator of battery life, not so the cycle count.

(new battery comes with ~8200 mAh that gradually over 5 Years goes down), once it reaches below 50% you will get the Service Battery.

Replace it.

You current consumption Amperage (mA): -2579 has nothing to do with anything, it is a variable that changes depending on the load.

If you plug in the Charger that number will go positive. (= Charging)

Also the remaining charge has nothing to do with battery life.

SMC can not read the battery values directly. There is a chip (IC) integrated with Battery called a SMBus chip or Gas Gauge or even Dipstick. It reads the analog values from the batter, coverts to digital and sends that to the SMC.

That is how it is possible for SMC to know the cycle count (and other values) even when you move the battery from one Mac to another.

An SMBus battery contains permanent and temporary data. The battery manufacturer program the permanent data into the battery, which includes battery ID, battery type, manufacturer’s name, serial number and date of manufacture. The temporary data is added during use and contains cycle count, usage pattern and maintenance requirements.

To your second question ...How to see if SMC reset worked.

While doing it, watch the MagSafe plug light, it will briefly flickers if the reset was successful.