Air Conditioning / Heating Unit , no air coming throught the vents (2007 Toyota Prius)

What is the condition of the cabin air filter? I know for my car, it gets pretty dirty in about 15k miles. If it hasn't been changed for awhile, it could be clogged up.

 

Can you hear the ventilation fan running? If so then you might suspect the cabin air filter blocking air flow. However if you do not hear the fan running, then the suspect components include the blower motor, the blower motor controller, the AC amplifier or the wiring harness.

 

The blower fan is below the cabin air filter. You may be able to check to see if the fan is rotating when you have the cabin air filter out.

 

Looking at the service manual, it appears that you must remove that blower assembly as a unit, then remove the blower motor from the unit. Of course, you must remove the passenger side lower dash assembly first. It looks doable by someone who is mechanically inclined.

As Patrick pointed out, there are a couple of other components that could also cause the problem, but if you pull the blower motor, or at least get access to the power connections, you could apply 12v directly to the motor to see if it is the cause of the problem.

You can get the service manual info at techinfo.toyota.com. You have to subscribe to access the manual, but you should be able to download the sections that you need as PDF files.

 

funny thing, mine just started doing the same thing. 2007 69000 miles. Sometimes it will come on and stay on while I'm driving until I turn the car off. It almost seems like a loose connection 'cuse it came on one time when I shut the door on the passenger side but that might have been coincidental. i'm not trying to hijack your thread but it sounds like the same problem. I dont think its your blower motor.

 

update: I pulled off a plastic cover from below the glovebox. There is a small metal box with a plug with wires going into it. If I tap on the bottom of the box near the firewall the a/c blower starts up. Maybe someone on here with a book can tell us what this box does. I tried wiggling the plug and reinserting it a few times but that didn't help. Tapping on the box always works. I also hear a strange noise from my fan motor so it might be going out too. If I run it on high the output is inconsistant. I need to replace it I guess.

 

Can you post a photo of the "small metal box"? There are a few items that could fit that description. It looks like the blower motor control should be slightly below and to the left of the cabin air filter access door. Maybe that is it?

 

Note the rotary control located to the left of the steering column, which allows you to adjust instrument panel brightness when the lights are turned on. Make sure that you've tried adjusting that control, before you complain to the dealer about that particular issue.

Can you find a part number on that box or else take a photo of that item? Sounds like this might be the AC amplifier.

 

this is the pic you wanted.

 

I'm currently traveling in San Diego and don't have access to my repair manual but dogfriend probably can identify this when he next appears on the forum.

Try this website to see if you can find the component:
http://www.toyodiy.com/parts/

Or, if you remove that component and take it to your dealer's parts dept, they can identify and order a new one for you. Sounds like you are well on the way to obtaining a solution for your problem.

 

I believe that item in the photo is the blower motor controller. It receives a signal from the AC amplifier and then controls the speed of the blower fan.

I am pretty sure it is not the AC amplifier because a) the amplifier is close to the center of the IP, behind the lower center cover and b) the AC amplifier has different electrical connectors than shown in the photo.

 

ok I took this part off it says transmission control. Is that for the blower speeds?

 

I called Toyota service dept and this part is for controlling the car transmission $600. Nothing to do with the blower motor. Just happens to be mounted there. I am leaning toward a bad blower motor $150. It still comes on sometimes but doesn't seem to run full speed and makes a little noise.

 

That is a weird one - the manuals show the HV computer mounted higher and to the right. Also, a Google search for that part number came up with some Ebay parts with some people calling it a "Body Computer". I do not know.

 

Yes, the part number label helped, and your service dept gave you a good identification:
ToyoDIY.com

You are probably right regarding the blower motor being intermittent. If you've removed and replaced the wiring harness connector and that doesn't help, try using a voltmeter to measure voltage at the wiring harness connector. Then, use an ohmmeter to measure the resistance across the motor. If you get weird measurements that will help pin down the issue.

 

Here is my plan. I ordered a new blower motor assy. from a Toyota dealer today . It will be in tomorrow morning. I will drive there and pick it up and bring it home and install it. Then I will give a report of whether that fixed my problem or not. The blower assy is $148