Ok,I got my a/c hooked up...when I flip the switch up to high the blower doesn't blow air, this is how it works,

Low- yes

Both Medium - yes

High- NO, it blows low

the resistor has four wires going to it, the black wire is solo, and the other three are together.

Bad resistor?
Thanx

 

Maybe a bad switch. If you unplug the resistor, nothing will work except for HIGH. (I have mine unplugged because leaves in the vent caught on fire.)

Try that.

 

I unpluged the resisitor except for the black wire, nothing worked, I changed out the speed select switch and the same thing, no High.

 

I have a similar but different problem. When I have mine on high there are times when I hear a ping or click and the fan blows a little harder then another click and the fan goes back to a lower setting. How hard is it to replace the switch? I do have another HVAC control that I can take the switch out of.

 

Not hard at all, you will need to pull the HVAC control out, the switch is held on by a srew, unscrew it. remove the chrome or black **** first. Since you have another control take a look at the switch you will see the screw.

 

You have a break in the wire between the blower motor and the A/C blower switch.

To test the switch, set it on high with the ignition switch in run, check the orange/black wire coming out the back of the switch. It should be hot.

The blower motor resistor changes resistance on the blower motor's ground wire to adjust speed.

There is a splice in the orange/black wire where it wyes off and one section goes between the blower motor resistor and blower motor, and the other section goes to the Blower switch. When the switch is on low, or one of the mediums (2), the blower motors ground goes through the resistor. When on high, the switch connects the blower motor's ground direct to ground.

Check the Orange/Black wire between the splice and the blower motor switch for a break.

 

Ok, no power on Orange/Black wire behind fan speed switch...didn't see any breaks where it y's...

 

Ok, turn the fan speed switch to one of the medium settings.

If the switch is bad, and not the wiring, you should have power on the Orange/Black wire at the switch as it back feeds from the wye from the resistor toward the switch.

If the Orange/Black wiring is bad between the switch and the splice where it wyes off, it will still be dead.

This is assuming your blower works for medium.

 

Mediun setting is good, still no power on Orange/Black wire...Ill check it tomorrow, I think the guy who wired it crossed something..

I really appreciate your help..Thanx

 

The Orange/Black wire is the main ground wire from the blower motor.

The Blower switch basically changes the pathway to ground. Either directly to the switch when switched on high, or through the resistor for the medium and low settings.

Since no power is getting to the blower switch at all in either mode on that Orange/Black wire, this is the problem wire.

For it to work on medium and not on high in this state, it has to be the wiring between the wye splice where it connects to the blower motor/resistor pathway and the switch.

The orange/black wire has to be functional between the motor, the wye splice and the resistor for medium and low to work, unless your guy who wired it, bypassed it somehow. If you see where I'm at with it.

Your welcome.

 

I just replaced my blower motor last week. The speed selections were working, but barely. My plug connection at the motor had crumbled. When I wired it back together, I could here the motor run, but had no air volume.

I put the new motor in and could hear it run its butt off and still had no volume. I wound up connecting my black motor wire to the trucks orange and the motors orange wire to the trucks black. The truck air has never worked as well as it is now.

I do not know if this could help. Mine was just doing very weird things similar to you. The motor was around 22 bucks from o reilly.

Also to mention my trucks wiring is all intact. No cut and splices on it.

 

Up and running, man he cut wires all over the place and the orange/black wire was cut somewhere in the engine compartment...went to the junk yard and pulled a complete a/c harness from another truck..plugged it right in and voila...If I knew it was going to be this easy I would've done it myself..Thanx for the help....

 

Glad you got it up and working.

 

< Enter sounds effects from the 80s sitcom Home Improvement with Tim Allen >

Huhhhhhhhh?????????

Could be interpreted in different ways.

 

LOL, it sure could.

Now where's the embarasment smiley?

Ah yes...