Battery? Or SMC?
MacBook Pro, mid-2015, had been working fine, but updated to Monterey ~ 2 wks ago.
This next part can't say I remember exactly, since everything had been normal. But one day I pulled the charger cable and the red battery low symbol displayed. Re-attached to AC, and it came to life without a re-boot. Used it normally the next while.
I use this mainly like a desktop, and don't remember seeing an orange charge indicator.
One evening I used it as a portable. No issue, and the % charge remaining seemed normal. I put it to sleep, closed the lid, set it aside, still not on AC power.
The next morning, I wanted to see how much the battery drained overnight, so without connecting it to AC, I tried to wake it. It did not wake; it displayed the red low-battery symbol.
Again today, I disconnected from AC and attempted to wake it, but got the low battery screen. It restarted normally on AC, with the charge indicator ORANGE. Normal, I figured - low battery.
After it booted, I checked System Information, which showed an inconsistent result:
Charge Information:
- Fully charged: NO,
- Charging: NO,
- full charge capacity 0 mAh.
- Cycle count zero.
AC Charger Information:
Connected: Yes
Charging: No
I shut it down and reset SMC while attached to power. I read that should be shift - cntr - opt - pwr, held 12 sec. Did that, and when keys were released, the charge indicator turned green for about 1 second, then back to orange. It booted normally, and System Information was unchanged.
Repeating that procedure gave the same result. Did it a third time, now disconnected from power. Same result.
What to check next? SW? Battery? SMC board? Both requires disassembly, and I prefer to have what it might need to fix it. My thinking is that an electronic failure could occur instantly, but that it's abnormal for the battery to go from full capacity to dead, overnight.
Thoughts?
What's a normal discharged battery voltage i.e., when the machine would automatically go to sleep?
MacBook Pro 15″, macOS 12.6
