I had my 2005 Prius in the shop for a month. My Car didn't start. After replacing the CPU board it still had the problem. The dealer then replaced the wire harness. This is the main wiring for all the electronic devices from my understanding, kinda like the spinal cord or the car. After that was replace the AC didn't work because a sensor was not connected. So now I'm aware of little things and wondering if it is normal. So my question is: I notice with the heat on, the fan speed changes. Is this normal?
If you have the AUTO button lit on the Climate Display, then yes, the car will adjust the fan speed, as well as change the outside air mix, change the dash/foot air mix, and run the AC compressor to de-humidify as needed. The Prius really has a Climate Control system and not just heat and AC. It may run the fan more at first to warm up rapidly, then slow it down as it gets closer to your target temperature. If the AUTO button isn't lit, then the fan speed should stay wherever you set it.
