HVAC Fan Issue

Hey All,

my HVAC fan only works on the highest fan setting. AC works, the light lights and I hear it kick on, heat works the same but I’ve got no fan on any setting but the highest.

Replaced the whole controller thinking that was it but no dice. My old controller also had lights out and broken knobs so that wasn’t a total waste, but still.

Anyone have any ideas where else to look? Just the blower motor it’s self?

Thanks

 

Here you go

https://www.tacomaworld.com/threads/before-you-replace-the-blower-resistor.107093/

 

Yep, it’s your resistor

 

Yup, resistor…easy repair.

 

https://www.tacomaworld.com/threads/2nd-gen-information-diagnostics.784008/#post-28042158

 

Awesome thank you so much all. Parts ordered.

 

Well, got the new parts and did the swap over the weekend. The new parts are what I understand to be the newest parts with the resistor and new pigtail being a square rather than flat all in-line wire pigtail.

After the swap, everything worked great. All fan settings good. Then today I'm back to only the highest fan setting working.

 

See if it blew the resistor again, if it did then first check and make sure your cabin filter isn't plugged.

If the filter is good then you likely either have a blower motor that is drawing too much current or just got a shitty part.

 

Thanks so much for the info. If I pull the resistor out, will it be obvious looking at it that it is blown?

 

Just as a data point, here’s what my old one looked like.

 

Usually not, it's usually the thermal fuse that blows on them. Which you could check that with a multimeter.

 

I ended up ordering another resistor, this time aftermarket. And a new blower motor and cabin filter (both aftermarket as well). Should be here end of week. I'll post how this works out

 

Alright. New parts installed.

Another new resistor
New blower motor
Cabin filter

Pulling the blower motor, it was pretty dirty. There was some resistance to spinning compared to the new one but certainly not seized. And the old cabin filter was pretty packed and dirty.

And this was obviously why it stopped working again after replacing the resistor the first time. But I think this is the designed failure mode, so I’m hoping the extra draw from the dirty filter and old motor was the cause.

It all works again just hopefully permanently now.

 

Eww yea that is pretty bad although I've seen worse.

Looks like the thermal fuse on the resistor failed as designed either due to lack of airflow and/or overcurrent from a bad blower motor.