Tried the 35 second fix but machine (Vertuoline Evoluo) remained in double-blink. Turns out it had three separate issues, so below is a combination including several previous fixes. Worked for me so hopefully it helps someone else. 1) Air pocket in water line: Prime it using a turkey baster or clear flex hose. Match the diameter of the tip to the water intake O-ring (mine was red) by wrapping tape around the tip of baster. Force water into the intake slowly, under constant pressure. The water level inside the turkey baster should go down steadily as you do this. Depending on how long since last use, I suggest injecting 1/8 ~ 1/4 cup. 2) Top disc: Any clicking noise is the sound of the wheel trying to spin freely. It must be cleaned until it spins with no effort. Use wet paper towels to clean all grounds out and avoid cutting your fingers on sharp teeth. After mechanical cleaning I turned my machine upside-down and rinsed the top disc out thoroughly under the kitchen sink. 3) Lower pod-holder: This too must...

iFixit's procedure is quite long giving you too many ways to screw up. I used an alternate method which is much quicker. Worked perfectly in my A1398 which is on its third battery. Hopefully this advice helps :)

If you are not careful by nature just pay Apple to do it. But if you are methodical you can save a lot of time and money.

> Alternate procedure:

youtube.com/watch?v=ayzzXKa1HOA

Much simpler method that avoids removing motherboard. Just go slowly.

> Cake spatula to help remove old battery (or floss or fishing line)

https://a.co/d/dvYzmVC

> 99% isopropyl alcohol (not 70%) as solvent to help remove factory glue

https://a.co/d/dxuN1TU

> Plastic pipettes to place alcohol

https://a.co/d/6zdvZVp

> Cover mainboard with towel or the supplied cloth

> Prop up rear hinge 1 inch so solvent flows away from mainboard

> Add bit of Loctite blue (242) to each screw when replacing

> Afterwards reset SMC and PRAM

Left Ctrl+Opt+Shift + Power

Hold CMD+Opt+P+R + Power

Fully drain battery, fully charge, then fully drain again