Power-related sluggishness?

[laptop_stacks]

Hi folks. I recently purchased a used MacBook Air 2012 11" with a blown-up battery. With the battery removed, the unit looks to be in good shape, passes pre-boot diagnostics, and I've successfully installed MacOS. I am having a few issues with it that I'm hoping can be fixed.

I first noticed that the unit will boot as soon as the power adapter is plugged in. There is no battery in the unit, but the charger stays solid orange. I have tried 2 oem chargers with the same result. I'm wondering if there is a fault somewhere causing the power to come on without hitting the power button and perhaps causing the unit to think a battery is installed.

Possibly related to this is the unit's extremely slow performance. I noticed in recovery mode that the mouse lags, everything takes a while to load. In MacOS, the computer is so slow its unusable. I suspected a bad 64GB SSD, and purchased a 128GB unit. No change. If its a memory or CPU issue, diagnostics doesn't show it.

Any ideas on the issue or a possible fix?

 

[ZapNZs]

I believe, at least with the 11 inch Airs, that plugging in the unit to AC power when there is no battery or a non-working battery or a battery that had been fully drained will, by default, power on the system. Someone smarter than me can confirm that.

Older Apple documentation stated that, if the battery is removed from a MacBook or MacBook Pro, the system will run slower so that it does not draw more power than the AC-only power source can provide. I am not sure if this applies to the Air or not but it would make sense.

 

[cruisin]

The orange light is likely an indicator that the Mac knows it is missing a battery (there is no battery to report that it is full). Mac devices know what they always should have installed, and will constantly nag that something is missing. I remember someone wanted to use a Mac without the builtin WiFi card and had many issues.

The booting on power connection is likely linked to the missing battery. What happens when you cover the middle pin with tape before connecting? On a working Mac it will give power but it won't change the battery and it turns off the indicator led on the cable completely.

The slowness is common to a battery powered Mac that doesn't have a detected battery. You need a battery of some kind connected, even if it barely holds a charge. The reason is that the power supply is rated for average power usage, and if your Mac is cool enough to take advantage of turboboost it will "borrow" power from the battery. Using the tape trick above I can use my Mac without charging the battery but it will slowly drain the battery if I am using a lot of power.