A/c fan speed fluctuation
#1
Lead Lap
Thread Starter
A/c fan speed fluctuation
The a/c fan speed in the automatic mode has been fluctuating from one speed to another more frequently than usual. The speed will increase and than decrease without me adjusting the temperature on a more frequent schedule than it had before. Does anyone know why this is happening and/or what sensor might be affecting this issue? This has become somewhat annoying. Thanks all.
Last edited by Bocatrip; 10-15-14 at 12:30 PM.
#3
Lead Lap
Thread Starter
I keep mine in recirculate most of the time as well, but it is still in the automatic mode. I have Nav and in order to change the speed of the fan I would have to go into the climate control of the screen to change it which of course is a pain.......therefore I'm usually in the auto a/c mode.
#5
Lexus Champion
In auto mode, the blower speed is determined by the "Duty Ratio", which is the percentage of time the A/C compressor is "ON" within one On/Off cycle. One way to prove that your blower is functioning properly is to adjust your temperature setting up (hotter) which will reduce the compressor run time and keep the blower at a slower speed, or turn the temperature down to extend the compressor's run time which will keep the blower at the faster speed.
#6
Lead Lap
Thread Starter
In auto mode, the blower speed is determined by the "Duty Ratio", which is the percentage of time the A/C compressor is "ON" within one On/Off cycle. One way to prove that your blower is functioning properly is to adjust your temperature setting up (hotter) which will reduce the compressor run time and keep the blower at a slower speed, or turn the temperature down to extend the compressor's run time which will keep the blower at the faster speed.
#7
Lexus Champion
Let's try this... On your next drive when your blower begins to change speed frequently, drop the temperature setting by 3 degrees and see if the blower stays on the faster speed. It's possible that the ambient temperature makes your compressor to cycle on and off so that your duty ratio is too close to the switch point. I really don't think your blower motor is failing.
Trending Topics
#8
Lead Lap
Thread Starter
Let's try this... On your next drive when your blower begins to change speed frequently, drop the temperature setting by 3 degrees and see if the blower stays on the faster speed. It's possible that the ambient temperature makes your compressor to cycle on and off so that your duty ratio is too close to the switch point. I really don't think your blower motor is failing.
Thread
Thread Starter
Forum
Replies
Last Post