A/C blower Mystery

Is the problem:

1) that the correct volume of air is coming out of the vents, but the air is not cold, or
2) that air volume out of the vents is lower than it should be given the fan speed selection

If 1) the refrigerant level may be slightly low due to a leak in the system.
If 2) the fan motor is probably becoming intermittent. You would need to replace the motor to solve that problem.

 

Yes, a DC motor has contacts which provide electrical power to the rotor windings. As the rotor spins that causes the contacts to wear. The electrical conducting surfaces may develop a coat of dirt and/or corrosion which prevent good transfer of electrical power. All of this causes the motor to fail after providing many hours of service.

 

Ok just to be clear, the fan is working but there is "no air" or just no cool air?

If it's the latter then an overheating inverter will explain all of your observations.

 

Buy a gallon of Toyota Super Long Life Coolant, and fill the reservoir to the top mark.

If the inverter overheats then it will not provide power to the AC compressor. However that doesn't seem to be your car's problem.

If the fan noise is at an appropriate level for the Hi fan speed position and yet the volume of air does not increase, the problem may be that the air is not being fully routed to the dashboard vents, but rather to the floor at least partially.

What position do you have the vents set to? If they are not set to the dashboard vent position, try that. If they are set to the correct position, it could be that the motor that moves the vent position is not working properly.

 

I'll take a guess and say you might have lost some of your refrigerant charge. And now the evaporator is icing up from hot and humid Florida. It could be stepper motors somewhere in the HVAC system affecting air flow. But it sounds more like ice buildup is restricting flow. You can try an experiment. The next time the airflow is restricted, go to the MFD Climate screen and toggle the A/C off with the fan continuing to blow. If after a couple of minutes the airflow increases, then I would suspect the above to be true. Then have your refrigerant level professionally checked and get any necessary repairs.

 

It wont power the aircon compressor if the inverter is overheated. Like I said, it only explains it *if* there's still plenty of air flow but it's just not cold. I was a bit unclear of about that point.

 

Just a good guesser sometimes. The other troubling matter now is where did the refrigerant leak from? It will continue to leak until repaired. That would not leave me with a good feeling.