My AC recently went out in my 2013 Prius C. The compressor is not turning on and there is plenty of pressure on the low pressure side, so I'm not thinking it's a low pressure switch. Is there a relay for the AC compressor? I can not find one in my book or in the boxes. Also, which fuse controls the compressor? I saw the 7.5 under the dash and it is fine, but the compressor needs more than that, so I'm guessing there is something else? It never made any bad noises and was working well. Then it just stopped. Thank you for and info.
The compressor is all-electric. It is electrically driven and the computer varies the motor drive speed with demand. That's done at high voltage under the hood, so no low-voltage fuse directly corresponds with it. Leaks are overwhelmingly the most likely causes. @lech auto air conditionin is the forum expert on this topic, but this is his busy season so he might not be able to get on the keys.
I don't know how it's done in a c, but collecting the trouble codes from the HVAC system in a Gen 3 liftback or a Gen 2 is done by holding down the AUTO and FRESH/RECIRC buttons while turning the car on, then reading the two-digit codes from the HVAC display. I would guess it's something like that in the c.
Thank you. That did work on the C also. I got error code 13 which appears to be a temperature code from the evaporator sensor. I'll start looking at wiring.
Solved. It was the evaporator temperature sensor, aka heater core sensor. It plugs in on the lower driver's side. To verify, unplug the old one and plug in the new one. The compressor will turn on, if that was it. I took the whole dash out and put it back in to find the issue. It took about 1.5 hours. Not a bad job. Mostly snap fit besides the 4 clips and several screws. I find the part at advanced auto. $38. I did not pull the evaporator, instead I cut a hole. Nothing pella couldn't fix.
Do you need to remove the dash? can't you access it from the driver side, from the brake and gasoline pedals?
You can access the plug without removing the dash. Unplug your old sensor and plug in the new one. Whether you install it in the evaporator or not, it will allow the compressor to turn on. To replace it, you either have to pull the dash and take apart the housing, or you can remove the lower part of the dash and console be carefully cut a hole in the housing and pull it out. There may be other ways, but I had to hold dash out to find out.
Yeah i see what sensor it is, is the one below the steering wheel, a little bit to the right, where there is a small vent to the right side.
The one below the steering wheel, with the small vent, is the cabin temperature sensor. The evaporator temperature sensor is inside the heater box, on the evaporator. Both are temperature sensors, and a person could have a car where either one happened to be at fault, but there's a big difference in how easy they are to access, so a person would want to be pretty clear about which one to work on.
