Chrysler Repair: Only one blower motor speed for vent. fan: Sebring Sedan, electrical resistors, vent fan

Question
Good Day..I have two questions .First. My A/C and Heat only comes on number 4...Second. When i'm driving I hear a slight noise around 25 to 30 m.p.h. like a soft rattling sound after I go above or under that speed limit I don't get it.I have been to several shops and everyone says it's fine...But I would like another opinion...Thank you ...And have a Nice Day...

Answer
Hi Byron,
The blower only working on speed 4 is a classic symptom of the component that divides the voltage from 12 down to three lower levels (for speeds 1,2,3) by means of electrical resistors, called the resistor block. The block costs about $20 and is easy to replace. On the '95 coupe (the only manual I have for the Sebring) the block was located in the air distribution unit under the dash, positioned right in one of the ducts so that the resistors would be cooled by the passing air from the fan when it was "on". To reach it, you merely have to remove a "stopper" from each side of the glove box proper which allows the box to drop down out of the way so that you can see behind it to the distribution unit. You will see that the unit has a left half and a right half, connected together at a seam. Just to the left of the seam you will see there is a fitting with a 4-pin electrical plug and associated 4-wire harness(the other end of the harness is plugged into the blower motor located on the bottom of the right half of the unit). If you remove the plug you will see that the fitting is held in place by a couple of screws. Remove those screws and the fitting will come out of the housing and reveal itself to be the resistor block. Before inserting the new block in its place, make sure that the individual resistors do not touch one another. Separate them if so, gently, with a finger tip. Reconnect the plug. Close the glove box partially and replace the stoppers and you should now have all 4 fan speeds.
If your unit doesn't appear as I have described, then I would look for the block by locating the blower motor, and then follow the wire attached to the blower motor to find where the block is positioned.
I would be hard pressed to know what the source of the rattling sound might be, but if you feel it as a vibration in the vehicle or steering wheel then you might have a tire that is slightly out of round or a wheel that is likewise. You could move the tires from front to back and back to front and see if the rattle goes away. If it is now felt at the rear, then I would have the two tires on the rear checked for roundness at a tire center, just as they are when mounted. If one is more out of round you could ask them to 'match mount' the tire to the wheel, a process which takes advantage of out of roundness in the tire and the wheel and mounts the tire on the wheel to cancel out the differences as much as practical. That sort of specific road speed dependent vibration is often a symptom of an out of round wheel.
Let me know if you have any more questions.
Roland