I just can't figure it out....

My AC only comes on when the fan is set on Hi. When I turn the Fan **** on to high it clicks then it will start blowing air. When I go to turn the **** down to a lower setting..all I can hear air decompressing and then no response.

I'm not sure what the problem is..I just replaced the blower with a brand new one but am having the same problem..I don't get it...what is that clicking I'm hearing...why is it making a compression sound?

 

I am guessing its the switch.

 

probably the switch, since high comes on from different than any of the lower settings. see if it is making a connection, I think it is behind your dash

 

I would never be one to tell you I told you so but do you remember this post from November 25th. When you asked the same question. Back then I told you it wasn't the motor.

"Sorry to say this but you will have to get the control out of the dash and see if the controls are not providing voltage to the fan until it finally starts spinning. You could test it at the fan but chances are good the controls are screwed up and not putting out until the last position. I don't suggest you change anything until you do some investigation. Personally I don't see why the motor would run at high speed but not low speed. I truly believe the problem is in the controls. DO NOT SHOT GUN the repairs. I don't have the money to do that and I don't believe you do either."

 

I'm not exactly sure how the 4th Gen fan speeds operate, but if it's anything like the older chevys, it uses a relay with resistor coils for the speeds.

When the fan switch is turned to the max setting, the resistor coils are bypassed and full voltage is sent to the blower resulting in the max speed. When any other speed is selected, voltage is directed through a resistor coil that lowers the voltage to the blower resulting in a slower speed.

If the high speed works but no other speed does, typically the relay that redirects the voltage through the resistor coils is bad ..... of course, this is assuming the 4th Gen's blower setup hasn't changed since the 3rd Gens.

Hopefully someone else can chime in here and let you know if I'm correct, and if so, where the relay and resistor coils are located (usually under the hood).

Thomas.

 

I probably over looked your suggestion. I got the motor brand new for cheap...like 28 bucks compaired to $150.00 O-well I got the car half way appart might as well pull the DAsh again....for the hundreth time.

I checked all the relays and they were fine...Your right the 4th Gens use a resistor coil also.