2018 Macbook Air Dead Battery, high fan, sluggish

[partyboy4357]

I have a 2018 Macbook Air that shows no signs of liquid damage but the battery is 100% dead and when running it off of power the fan speed is high, performance is super sluggish. Tried SMC, PRAM etc resets to no avail. Running diags shows battery needs replacement but that shouldn't cause the performance/fan issues should it?

 

[1BadManVan]

I have a 2018 Macbook Air that shows no signs of liquid damage but the battery is 100% dead and when running it off of power the fan speed is high, performance is super sluggish. Tried SMC, PRAM etc resets to no avail. Running diags shows battery needs replacement but that shouldn't cause the performance/fan issues should it?

it might, if you intend to keep it, might be worth just trying the battery atleast and see what happens

 

[Giuanniello]

Same issue here, I got a broken screen 2018 MBA, opened it, detached the display connector as to force booting off external screen and it works but a dead battery makes it all sluggish to say the least and the fan spinning like a pulsar star, wondering if replacing the battery and using it as a desktop makes any sense

 

[chrfr]

Same issue here, I got a broken screen 2018 MBA, opened it, detached the display connector as to force booting off external screen and it works but a dead battery makes it all sluggish to say the least and the fan spinning like a pulsar star, wondering if replacing the battery and using it as a desktop makes any sense

A new battery should solve the fan and some of the sluggishness, but a 2018 Air still isn't a fast computer at all.

 

[Honza1]

Dead battery will slow down Air or MBP. Battery is used as backup power in case power source momentarily does now provide enough for the system. This is well known and can be googled easily : if the battery is dead/not connected, system will slow down CPU to prevent accidental reboots. I had the same thing on older MBP and battery replacement fixed that. It will not, though, fix the screen ;-)

 

[sack_peak]

Excluding the dead battery try updating your Mac to macOS Ventura 13.6 or macOS Sonoma 14