Blower speeds

[LawrenceB Herwitz]

I've had my 2002 ST for almost 8 years. The climate control blower has always been flaky to say the least. It is always blown well in first second and fourth speed. Third speed is always been equal to the second. Just recently now I have speeds one and four. Could this be the climate control switches. Or what do you think. The air-conditioning works fantastic in this just the blower speeds are off.

 

[Lloyd Ledford]

1 of 2 things--speed switch or blower resistor.

 

[Yardsale]

I'd check the blower resistor first.

 

[Vic Sorlie]

It's the blower motor resistor, and is a very simple fix. Check YouTube for a DIY video.

 

[LawrenceB Herwitz]

Thanks. I found the how to's on YouTube. Seems easy enough (famous last words)

 

[Mark Price 2]

 

[Robert Howell]

Not a bad video, 2 things though. Don't twist the wires before crimping, it breaks strands and fatigues the crimp to wire MUCH faster. The crimps he was using is heat shrink and seals way better than black tape.

 

[Mark Price 2]

Ha. Oh yeah. I was thinking the same thing while watching the other day. Glad you mentioned it. Good catch.

 

[Bob McDonald]

Basically, the blower is a single speed motor. They control it's speed by progressively inserting more resistors in the circuit, using the motor resistor assembly mentioned previously.

 

[Mark Price 2]

That's got me thinking. In a case of fried resistors/wiring. Maybe not a bad idea to check the blower itself for smooth spinning. What if the squirrel cage is binding and causing an even higher resistance or drawing more amps. In turn, frying the resistors/wiring. I don't know if this is an issue or it works quite like that. . Just a thought. Does this make any sense to anyone? Or is it just 2am and I'm delirious?

 

[Robert Howell]

Added drag of the fan/motor would decrease electrical resistance in the motor, increase current across the entire circuit and also reduce cooling air over the resistors. It makes sense, all adds up to more heat..

 

[Yardsale]

Fan binding or rubbing is not a problem I of which I have heard. Typically, the wires ("resistors") corrode and fail.

 

[Mickey Luis]

I had the experience less than an month ago that Markaprice mentioned. Changed out the resistor due to only high speed fan only working and all speeds worked. Within a week blower went back to only high speed. After tracing circuit wires, relays and replacing resistor connector low speeds still didn't work. Finally checked fan blower itself and found it binding. Fan binding had caused brand new resistor to burn up again. Moral of story for me, was to check fan for binding first before replacing resistor.

 

[Yardsale]

What part was binding? The "squirrel cage" fan, the motor shaft bearing or something else? What fixed it?

 

[Mickey Luis]

The fan motor shaft bearing must have went bad, the cage and motor brushes were fine. Fan motor was a "Four Seasons" aftermarket item from Advanced Auto only 2 or 3 years old. Replaced motor with a used spare Motorcraft and a (second) new resistor fixed problem.

 

[Yardsale]

Fan binding or rubbing is not a problem I of which I have heard.

I meant fan, not motor or bearing.



I'd bet that used Motorcraft motor outlasts the "Four Season" motor.

 

[John Zuber]

My sons 2009 Honda Fit blew a resistor...the problem was the fan motor...actually the crap bearings. Honda even has a "trouble report" on this for the mechanics...but of course they wouldn't do anything to help. The point is that a blown resistor can go because of motor drag.

 

[LawrenceB Herwitz]

Update on mine I change the blower motor resistor and now I'm back to speeds 12 and four but speed three does not work it is the same as speed 2

Does anybody think that might just be the switch in the AC control panel

 

[Yardsale]

Did you notice any failure on the blower motor resistors you replaced?



So, now it's back to the state it was in for many years (1, 2, some 2-like speed and 4)?



As a sanity check, check the new resistors. They can fail with age, but can also short-out. If it's bad again, you'll need to find the source of the problem.



If the resistors are good, I'd check the switch to see if two positions (probably 2 and 3) are shorted and sending current to the same resistor.

 

[LawrenceB Herwitz]

I bought a new blower motor resistors. And the electrical connection that connects to it looked good too so I didn't replace that. I have a feeling it's just the switch.