heater/AC blower fan problems
06-23-05, 06:35 AM
#1
"A Piece of Work"
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heater/AC blower fan problems
My blower fan is not working on the first two fan speeds. I have checked the switch and swapped out fan motors with no success. I have read where there is a resistor that has something to do with the fan speeds. Someone said it was on the side of the blower motor. Is it on the outside of the motor housing towards the top or where. Can someone help me out here, because I believe that is what it has to be.
Thanks,
Todd
Thanks,
Todd
06-23-05, 08:43 AM
#2
Certified Old Fart
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Might help
I haven't had an rx one apart myself, but generally you are looking for a thing with and in and out wire connection, and between the two posts are several coiled wires. This wire is the resistor and heats up and is cooled by the passing air. Any I've ever seen are more or less the same. Usually, they are attached to the heater box itself, in the passing airflow. The wires eventually just melt and break, and voila, you are missing that fan speed.
06-23-05, 01:04 PM
#3
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As I recollect, the resistor (a nichrome wire coil) is evident when you pull the fan motor. And I believe you can use a unit from a Pinto or Escort if they don't have a 7 at the JY. Take along your old unit for comparison.
B
B
06-23-05, 07:22 PM
#5
84SE-EGI helpy-helperton
Yep, you guys are all on the right track. When my 1 and 2 speeds on the fan went out, I removed the motor, looked up into the air path and saw the broken wire coils that resist current to give you the variable fan speeds.
On removal of the airflow/fan shroud, you can remove the 1"x2" plastic base that holds the wiring for the resistors and the plug for the A/C system. Unplug the wiring and then have a look at the coiled wire resistors. I happened to have a spare air duct in the garage, so removed the coils that were burned out and re-soldered them into the correct positions. There's nothing saying that you can't just go down to Radio Shack and have them test the resistance and give you ceramic block resistors - they will perform the same function.
As stated, when the air blows across these resistors it keeps them cool, thus allowing them to resist the 12v current to the motor. If you have a 5-speed fan (off being speed 0), then you will have 3 sets of resistors. Full speed is zero resistance, i.e., full 12v from the battery. Hope this helps,
On removal of the airflow/fan shroud, you can remove the 1"x2" plastic base that holds the wiring for the resistors and the plug for the A/C system. Unplug the wiring and then have a look at the coiled wire resistors. I happened to have a spare air duct in the garage, so removed the coils that were burned out and re-soldered them into the correct positions. There's nothing saying that you can't just go down to Radio Shack and have them test the resistance and give you ceramic block resistors - they will perform the same function.
As stated, when the air blows across these resistors it keeps them cool, thus allowing them to resist the 12v current to the motor. If you have a 5-speed fan (off being speed 0), then you will have 3 sets of resistors. Full speed is zero resistance, i.e., full 12v from the battery. Hope this helps,
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