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My Macbook Air (2018) Retina battery has depleted within 130 cycles. I was running Windows via Bootcamp in heavy load, letting it discharge fully and charge repeatedly. If I unplug from power source the system shuts down. Battery status is showing as “replace now”. Coconut Battery test shows that current capacity is 9 % of design capacity. The system when connected to AC power turns on but it is running extremely slowly. When checked activity monitor, Kernel_Task shows 300 % of CPU. Apple Diagnostics test revealed one issue PFM006 - SMC issue. I tried resetting SMC, PRAM. Issue still exists. My questions are Is PFM006 (SMC) related to Battery. If battery is replaced, will this issue go away? Else could it be a faulty temperature sensor?Is the Kernel_task issue related to PFM006 (SMC)?Could there be any relation between these three events (PFM006, Battery, Kernel_Task)?Does apple diagnostics cover all sensors? If PFM006 is the only error returned, does that mean all sensors are working fine?How is it possible for a battery to depleted within 130 cycles when it is guaranteed as 1000 cycles? Note: All apple service centers are closed due to COVID-19. So trying to find the issue online.
To start with you have a case to get a free battery under warranty! You’ll need to go to an Apple Store. Make sure you have a printout of Apple T/N Battery info Determine battery cycle count for Mac notebooks and you’ll want a snapshot of the Battery info from CoconutBattery As far as your direct questions 1 - SMC and your battery talk which each other, the battery tells SMC its temp and its battery levels via the one wire comm link (middle pin in the MagSafe connection) it also controls the color of the MagSafe as well. The error you got is a battery error with its sensor. 2 & 3 - Yes! When SMC is not getting a proper signal from the battery as well as other sensors within your system it will go into Safe Mode which lowers the CPU’s clocking (creating these excessive Kernel_Task’s) 4 - The onboard diagnostics does not cover all of the sensors. Thanks Apple! Over the years Apple has trimmed its onboard digs down and at one point offered a full diagnostic tool, all gone! Support the Right to Repair movement!’ 5 - It shoundn’t die this soon! And yes, COVID-19 is making it hard! You’ll need to call into Apple Support to get an appointment to the nearest Apple Store (hopefully opened soon) otherwise you’ll need just to get it documented so when the store opens you can get your system serviced. You could try to get repaired by shipping your system in. Given your condition here its best to stick with an Apple Store Vs an authorized service center.
