Solar Roof Troubleshooting

New to a 2014 Prius with solar roof. The manual says to press the switch when the car is on. I did that and came back to the car and heard the fan running (passenger side at top of hood/bottom of windshield). Wasn't sure if you need to press the switch every time before you leave the car but I did not and I heard the fan running again when I returned to the car. Was a hot day, maybe 75-80. Not sure if the fan operation is temperature controlled, would make sense that it was. The inside of the car was slightly cooler, I think, than if the fan was not running.

 

Adding to the problem of troubleshooting is the fact that after you turn the car off with the switch in (which enables the system) it will take about 10 minutes or so before the fan runs for the first time. After that it will cycle on and off, lower and higher as enabled by the amount of sunlight and as needed based on the air temperature (inside and outside the car).

 

Mine comes on after 10 minutes of locking car with fob. And no need to press the AC button, that’s manually turning on the AC with the HV bat so that’s isolated to the solar panel. Doesn’t matter the in or outside temp, it’s just the sun’s angle and intensity of the rays that will provide power. Mine runs during winter even when it’s colder than 50F no matter thermostat temp set during mid days.

 

With the solar package the primary fan is a higher capacity and there is an extra fan. You can leave the button depressed all year long in warmer US states. Doesn't do anything in Minnesota winters. Once activated, in about 10 minutes or so on a warm day you can hear the fan(s) running at different speeds as Walterm stated previously.

 

I can hear mine from outside of the car, if you find out what it is let me know I’m parting out my 2010 IV so I have some parts available.