I have four “speed” settings on my heating/cooling system, 1-4. All of a sudden, only 4 works! It’s high or nothing. Is the motor shot? or is it the switch? Also, the Haynes manual says to take it in and have a pro discharge the A/C system before disconnecting the blower motor. Is this something I could do?
The resistor panel for the speed selection has failed. Follow the wires back from the blower motor and they should lead you to the panel mounted on the air duct. Replace the panel with a new one.
With your eight year old Jeep, it is possible the fan may be getting old and drawing more current and that could have blown out the resistor pack.
I have no idea about that instruction to discharge the A/C when disconnecting the lower motor other than maybe to protect the AC if the blower is out. However I can think of better ways of doing that than discharging the A/C unit. That could cause more problems and expense.
Please Tell Us The Make, Model, And Year Of The Vehicle. Some Advisor May Be Familiar With It.
That way they may be able to tell you if you can do it yourself.
I just did a resistor (blew twice because of a worn blower motor) and a blower motor on my wife’s car. There were only eight screws involved, no A/C work, no special tools, but because of the location of the screws up under the dash, was a slow tedious process, requiring lots of patience. However, this job would also be hard for a technician for the same reason and therefore could be costly. My repair ran $20 for a new resistor (dealer part) and $20 for a low miles used blower (salvage yard). I got to practice removing the blower at the salvage yard, first, all part of the price!
I agree with Cougar’s resistor diagnosis. Also, sometimes a failing blower motor will cause the resistor to fail.
This Space For Rent
Sorry all, In my haste I forgot! It’s a '00 Jeep Cherokee Sport
I have a '96 Dodge van and the fan motor is bad. It howls some and growls some but the resistor has never failed yet. However I have a friend whose resistor is burned out and we can’t find it. If it ever warms up some we plan to take the glove box out, probably it is back there.
On my mother’s Dodge van it (the resistor pack) is under the hood on the firewall. (Installed so that the resistor part of it is in the air duct.) It’s up mid-way or higher on the right side.