The AC blower motor on my 2014 prius C has been acting up for quite sometime. It would work and make noise and then just recently you needed to give it a whack to make it work. It would go between low and high fan speed while driving. After reading a bunch of posts and watching videos, I ordered the part which arrived today. I unhooked the old blower motor this morning and plugged in the new one and it didn't work. I put the old one back in and now that one doesn't work either. It was getting power yesterday and the old one was working with assistance. Now it seems like it is not getting power. I checked the fuses and two of the ones I checked were fine but I replaced anyway. Not sure if there is another, even though I checked the fuse schematics. Any suggestions on what to troubleshoot next would be helpful. Next stop will be Toyota if I can't figure it out Thanks Jamie
The blower controller is built into the blower motor. There's a power and ground, and one (blue) wire from the amplifier. This wire sends a duty-cycle signal to the blower controller, and controls the speed. Check that the power and ground is good. Other than that, you'll need a scope or a DMM with a duty measurement in order to see the signal from the amp... Changing fan speed, a scan tool should verify the fan speed commanded. Then look at the signal going from the amp to the blower, and see if there's a corresponding duty increase. If the scan tool is showing the proper input speed, but the duty is not changing to the blower, then the amp is most likely faulty, or the wiring between the amp and blower is open (not likely on a Toyota).
My 2012 did this a few months back. I found that my up/down and off buttons were the culprit. I don't know if that's your issue, but I had to press them a few times to get them to resume original locations. Once I did that, I didn't have any further issue. But if you're display is showing fan on and your fan is not turning on, then you are having a different issue than I was.
