A/C and Heater Fan Failure Under Low Air Flow Conditions

I could tell you one thing I am 100% sure of. You did not take it to a knowledgeable Prius mechanic. This is a diagnosis I could stand behind.
This is always like diagnosing over the telephone when you think there’s some information that is missing that could lead you down the wrong road or recommendation.
Trying to read between your sentences between the
#1 cooling problem and the
#2heater problem
#3 interior blower Dash fan sometimes works and sometimes does not.
#4 When the interior fan does work on a hot day the air conditioning is working fine when you’re driving down the road but when you come to stop and go traffic when you’re standing still ?.
A: The air conditioning cooling turns off but the blower fan keeps running and you start feeling hot air?.
Questions
1: has the air-conditioning recently been recharged within the last year?
2: has the vehicle been in a front end collision where the bumper or hood or radiator support had to be repaired recently
3: has there been any under the hood service procedures performed for maintenance recently.

4: before having more parts shotgun repair style find a shop that specializes in Prius only and have been in business for more than 5 to 10 years at least.
The next best thing find a shop that specializes in Toyotas. stay away from the shops that specialize in everything Ford Chevy Chrysler Honda Mitsubishi Suzuki infinity Lexus

as for your heater problem there’s a lot of good mines on this form with a lot of experience combined between everyone here your problem may get solved.

 

I forgot to add one thing have your 12 V battery checked just in case funny things happen when they start to get weak.

 

Wow. Then n that case it sounds like, I feel sorry for the technician who has to diagnosis this car.
1: This car has never been in a flood ?.
2: Had a selvage title
3: Technician used Techstream on a test drive for confrontation of transaxle overheating?.

if all these things started happening at the same time Intermittently Did the technician start looking for bad grounds. Voltage problems.

Give the car to the technician to used to drive home using Techstream for a few days.

sounds like you need to catch the eye of someone here on PriusChat may have had exactly the same symptoms and solved it.

Since this is a hybrid specialist and I don’t remember reading that the 12V battery was tested ?. Or replaced ?.

I can’t wait to find out what finally fix’s this problem.

Since this is a hybrid Spectly shop he must be slammed with work no time to spare and by now this car is eating up his time.

 

I find it hard to believe that a Prius Specialty shop does not know how the fans work. They're run by two relays that can run them in serial for one speed and in parallel for the other speed. It is all in the electrical wiring diagram. Tell him to go look on Toyota's Technical Information System website.

 

Do you get the same impression that I get a lot of shotgunning of replacement of components is happening instead of diagnosing

 

Yup.