What else could be wrong with A/C ?

[Drewhenry]

Blend Doors are aluminum-I know they are not broken.
Linkage replaced with doors. New seals installed. Fan motor has been replaced twice(original lasted 11 years). Resistor has been replaced twice to be sure it was not the problem. Switch works fine.
Problems: Many times fan does not come on and must be bumped or kicked to start. This motor-2nd one I have replaced-less than a year old. It was a new part from Chrysler too.
There is a buzzing sound similar to a twig being placed in the spinning spokes of a bicycle wheel, but there is nothing contacting the squirrel fan. The sound gets worse as the ac runs and less & less air comes out of the vents. I have removed the fan and checked 3-4 times. Nothing is making contact to cause this noise.
I cannot figure out where the noise is coming from or what is causing it.
Could I have a cracked A/C case/housing? Could something be causing the doors to move from their respective positions?

Thoughts? Insights?

Andy B

 

[Dan_69GTX]

If air is not coming out elsewhere, it is the fan motor slowing down. Could just be a bad fan motor. Can't remember on the 04s if there is a relay for that motor or if it is just the a/c, body computer that controls it.

Check voltage and amperage at the motor. I'd guess you will find out that it is the motor. The buzzing sound gives it away.

 

[Tuesdak]

Bad connection is possible. Wiggle the blower motor connection and see if it starts. Wiggle the resistor wires next. My 2003 is known to also burn the ignition switch and connector. FCA makes both a motor connection repair kit and complete wire harness if the resistor connection is bad.

The noise indicates it's hitting something. Use a mirror or scope to check the wheel housing. Its possible you got a bag or other derbis making noise from airflow. Includes loose doors and seals.

 

[Dan_69GTX]

Jdoremire, Good point!,

When The blower motor is running, or not running fast, reach down and feel the wires and connections. Do you any feel hot? If so, fix that! Then continue, or you may have found the problem.

 

[MarkEagleUSA]

Another vote for the motor connector. My 03 had similar problems that turned out to be a bad contact from overheating. Looking at the connector was all it took... not burnt but definitely overheated and loose.

 

[Tuesdak]

Jdoremire, Good point!,

When The blower motor is running, or not running fast, reach down and feel the wires and connections. Do you any feel hot? If so, fix that! Then continue, or you may have found the problem.

Safety First! Use an IR temp gun as a temp probe as you can get a severe burn from touching a melting wire and the melted insulation can stick to you. OW! The IR gun is a useful tool to look for bad connections as they are hot. Just saying as most don't expect the resistance of the bad wire or connection to make the wire a burn hazard.

I have seen the connector to the actual wire fail, headlights on another ride, and assumed just the discolored connector was bad. I got burned from the wire near the connection rather than from the cool connector that I had checked first.

If the motor is slowing down as was pointed out as a possibility there will be a hot connection or wire. If something is dragging the motor ie: contact with the cage making noise the motor will draw more current, not cool well, overheat the resistor pack, and heat the wires up. You need to be sure (and you appear to have checked) that the motor isn't dragging on something.

You can carefully run the motor out of the box and see if it's making the noise. New parts don't mean good parts is so common with lack of quality control today.

 

[Dan_69GTX]

True - be careful of the gooey wires!

However, for a bystander it can be quite entertaining! Kinda like using a flyback transformer from a TV to charge some capacitors and leave them on the shop table for the next class.

Opps, I think I just dated myself there!

 

[TFucili]

My buddy's GC had a similar issue, minus the noise. Ended up tracing it to a broken wire buried in the loom that was a bear to find.

 

[Motorhead]

Hith the rubbing noise, the commutator could be gone or the bushings on the motor are bad and the armature of the motor is rubbing INSIDE the motor on the field shoes. Pull the motor and see if the shaft wiggles back and forth a lot.

 

[B.G. Smith]

Re: Clicking noise. Could it be a broken connector to one of the doors? Might be stripped out and the servo just keeps running till it finally shuts off the air? As for the motor, I would bet the problem is in the connection where the wires plug into the resistor for fan speeds. bg