Heater Fan Speed Eratic

[morphius909]

Hey Folks,

I'm sure I posted something similar last winter, well here we go again!

When I have the heat on, my fan speed (usually when it's in high speed)...suddenly, out of no where..goes to super high speed?

Any ideas? I think one or two of you mentioned this as well.

 

[MikesToy]

Hey Folks,

I'm sure I posted something similar last winter, well here we go again!

When I have the heat on, my fan speed (usually when it's in high speed)...suddenly, out of no where..goes to super high speed?

Any ideas? I think one or two of you mentioned this as well.

Do you mean it gets loud like an old electric fan?

 

[jharris2]

Is it in manual or auto mode?

 

[CJ3Flyr]

Mine does it too even in manual mode. It's as if it's chasing a temperature even though you've selected a fan speed. When using a manually selected fan speed it varies much less than full blown 'auto' mode. Some of the variation in noise comes from changing from fresh to recirc at will.

The only way I have seen the system be 100% stable is in manaul with the temp on high or low.

That's been what I have experienced. I don't think you have a problem just an annoyance

:cheers:

 

[Iowa4Runner]

My '04 has done this from time to time over the past year or so. The fan seems to get pulsed to the next higher speed for ~1 second. The fan speed indicator on the display doesn't change, so this appears to be a problem with the fan motor or the output of the fan power circuit.

 

[morphius909]

I've never run it in Auto mode, just manual.

I've usually noticed it when it is on the highest fan speed setting.

basically it "pulses" up to the next speed level, even though the fan speed is on high.

I guess I'll ask the stealership next trip in.

 

[Annoyed]

My '06 did this last night while I was running around looking at Christmas light displays. All of a sudden, the fan just went into a very fast speed.. too bad it doesn't go that fast on "hi".

I think I had it in manual control mode, but I'm not 100% certain.

 

[morphius909]

Intersting. Guess it effects all years.

I'll let you know what the dealer says. Still 2K away from next oil change.