No heat or AC, blower is working

Did you check the main radiator? Is it completely full of coolant? (take the cap off when engine cold, coolant should be right up to the top) When you are low on engine coolant, the first thing that goes away is cabin heat.

A lot of people change Prius engine coolant they do not properly bleed the system. The easiest way to bleed a Prius Radiator is to install this yellow funnel Amazon.com: Lisle 24680 Spill-Free Funnel: Automotive on the radiator neck, fill funnel 1/2 full then start the engine and run for 15-20 minutes with heater cranked on full.

If you don't have this tool, leave engine off and keep filling the radiator with a dixie cup a little at a time over the course of 2 hours until it absolutely won't take any more coolant.

 

It just got established (in post 18) that the air-mix damper linkage isn't moving. If air is directed around the heater core instead of through it, there won't be heat - we seem to have a prime suspect.

-Chap

 

And there won't be ANY heat if the radiator is low, no matter what condition of the stuff under the dash.
All I'm saying is the OP should have confirmed the radiator is completely full before proceeding.

 

OP reported coolant checked/replaced in post 5, and heater core tubing "very hot" to the touch in post 9. With focus, the problem is probably very close to being solved.

-Chap

 

When I saw OP say "had coolant replaced" that was a red flag for me.

I've had many Prius come into my shop that others have changed radiator, water pump, or coolant etc and most shops don't know how to properly bleed the Prius.

9 out of 10 times when a Prius has poor or no heat, the radiator is not completely full. If this has been ruled out then obviously the problem is somewhere else, but I wanted to make sure the radiator has been recently checked.

My comments may not help with this particular car, but perhaps others in the future will carefully check radiator before taking dash apart etc.
Here's a video under dash that may or may not be of use. Had one customer with pieces of the plastic linkage missing.

 

I had that linkage fall off on a clumsy accelerator assembly replacement. I had the part but weather was nice so I didn't notice I could not get cooling or heating. Once I got it back on, problem solved.

The real pisser was one of our dogs decided it was a 'toy' and 'modified' it. I had to get a replacement. No big deal but darn.

Bob Wilson

 

Wow, that looks busted all right!

Also weird. Is that the way it was when you took it off, with the steel pins in the ends of the white arm pointing back toward the motor?

If you look at the video in the post I linked to way early in this thread, you'll see the white arm is normally installed so those pins point away from the motor, and insert into the slots in the movable linkage pieces. (Edit: you can see that also in Paul's video in post 25.)

Do you remember any work done down there where that arm could have been taken off and put back on backwards? I don't think any mouse did that.

Officially, I don't think that arm is sold separately, but is part of the servo unit (available here). Unofficially, you could probably scavenge one off of a parts car, assuming the motor is otherwise ok but that arm is actually broken and not just on backwards. The picture does make it look pretty beat up.

-Chap

 

I have to say that looks a lot better - though the exposure is so light that I can't really make out whether the arm is damaged at all - it's all too white to see detail. Is it possible to install it securely on the motor so it moves when the motor turns, or is there really a break somewhere?

If it's not really broken, maybe the links had simply been knocked off of the pins somehow? It sound like Bob Wilson had that happen.

Reinstalling it is a little fiddly because, as you can see, there's a pin at each end of the arm, and each one goes into a piece of the linkage. You have to get both linkage pieces to line up with the positions of the pins while you try to set it into place.

The pin in the end of the arm that points more toward the driver goes in the linkage that controls the two air mix dampers (the parallelogram arrangement). The other pin, in the end that points more toward the front of the car, goes in the linkage to the extra-foot-heat damper (very long white linkage going to the pivot very close to the foot outlet of the heater). This is the damper that moves in the "interesting backflip" that the linkage does at the very maximum hot position.

-Chap

Paul, I just noticed in your video that it does not show the "backflip" motion and opening of the extra-foot-outlet damper at the extreme max hot setting. This is the damper with the pivot very close to the foot outlet, operated by the very long, straight white rod that runs behind the air-mix linkage to the farther pin of the air-mix servo. With the system in test mode you should see that it pretty much never moves except at the extreme of max-hot and then the linkage flips around to open it.

Do you think in your video you just never set the control quite all the way hot, or was the video shot in a car where maybe that link got disconnected?

-Chap

 

Ah. Yup. New motor time. Unless you find a good one from a donor car.

-Chap

 

You could clean the broken post and then JB Weld it. Dremel grind out any thing that shouldn't be there and put it back together.
It will run forever.

 

where is the info to change the blower motor and part for when you cut it?????

 

Replied to your other post.