Brakes broke!

It's the combination. One action lifts the adjust lever over the next starwheel tooth, the other action expands the shoes away from the parking strut and allows the wheel to turn by that one tooth. You get (at most) one tooth of adjustment each time you repeat the combination.

Under the Library tab on techinfo, you've got access to all of Toyota's service-technician training coursebooks. Both adjuster designs (this "parking-brake adjuster" style used in the Prius, and the "reverse-travel adjuster" used in some other models) are well explained there.

-Chap

 

Why don't you take off the rear wheel and brake drum.

Inspect the drum and shoes for uneven wear.
Replace if the drum and shoes are below specifications.
CLEAN: the drum, drum backing plate, brake shoes, and adjusting mechanism.
Relube the adjusting mechanism and apply grease to the backing plate comtact points; I forget the grease Toyota specifies for the adjuster and backing plate.
Adjust the shoes.
Test the parking brake.
Test drive.​

 

As soon as shoe removal is required with drum brakes, I prefer to pay someone. Lubing of the contact points I'll do myself (use moly anti-seize), but that's about it. Shoes and drums are very long lasting, fwiw.

 

WHAAAT? Disc front and Drum rear, about as INexpensive as any car on the road.

Sounds like when the ABS system drops out, the brakes lock up. GET IT LOOKED AT NOW, something is VERY WRONG!