Powering up a MacBook Air with non-functional keyboard I have a working MacBook Air (2015 model) with a non-functional keyboard.  Water was spilled on it accidentally which shorted everything out. A 3rd party local computer repair shop got the machine working again except the keyboard. Since then it's been used with a Logitech Wireless PC USB keyboard without any problem, putting it to sleep when done, and waking it up via the external keyboard. This has been working fine without any issue.

Recently the battery has completely drained out, effectively powering down the machine. Although the machine has been fully charged, it isn't responding to the Power button on the external keyboard.

What options do I have to make the machine boot again?
Various internet sources (YouTube, iFixit) mention that bridging two solder points with a flathead screwdriver will start up the MacBook Air.

The following iFixit question includes an answer showing the location of the two points in question on the 2015 MacBook Air:
iFixit.com

More images and repair guides also can be found on the iFixit site:
https://www.ifixit.com/Device/MacBook_Air_13%22_Early_2015

With liquid damage, the chance the keyboard fails and no other damage is done is very low. Be sure you’re prepared for a short to the electronics and a fire if you keep charging a liquid damaged and clearly non functioning device. It would be best to have someone qualified to make a safety determination look over the device if charging is now affected in addition to keyboard function.