Jeep Wrangler blower resistor

Answer 1

Like with a lot of people, the blower motor on my 1994 Jeep Wrangler lost the two lower speeds and I only had high speed. I discovered that the blower motor resistor pack is on a small board measuring about 1" by 2 1/2" which is actually bolted to the blower motor plenum using two small screws such that it hangs in the airstream inside the plenum. I'm told this is to help keep the resistors from getting too hot. It is located about 10" above the passenger's feet, facing toward the firewall, under the glovebox. Look for a small wiring harness with three wires and a socket that plugs onto the resistor pack. Remove the two screws with a 1/4" socket, and the pack comes out.

I replaced the pack with a new one and blew it out in less than a week. So I looked over both packs to see what was going on. When I inspected the resitors I found that both of them were fine, but there is an additional component in there, a cylindrical component about 1" long, about the size of a big diode. I think it's a thermal fuse, and it was an open circuit. I jumpered across it and things worked fine, so I soldered a wire to each end of it, drilled a hole in the little board and led the wires to the outside where I put a fuse holder and 10 amp fuse. Everything works fine now.

*tc0nn* The blower resistor is usually a $37 - $41 part at the national chains.The kit mentioned above cost me $24.xx at a local Jeep dealership.

ANSWER

In the Jeep, on the control panel, there is the "fan knob" that you use to select one of four blower motor/fan settings when using the air conditioner or heater. The first three settings run thru the resistor. The fourth, the highest setting, does not run thru the resistor but connects "directly" to the battery; this is why the fan will always work on the fourth setting. The lower settings are controlled via the resistor and will not work if the resistor is shot. You can only assume that the blower motor resistor MAY be shot. Why MAY? Because there is a possibility that the reisistor is ok, but the respective fuse is blown. The fuse is also located directly behind the glove box, that when the glove box is removed, you cannot miss the small fuse box. Check the integrity of this fuse before you pursue replacing the blower motor resistor. On the glove box, on the right side, is a sticker indicating which fuse is for what function and you can find the blower motor fuse using that diagram. Pull the appropriate fuse out and make sure it has not blown. If it has blown replace it and see if the blower motor then works properly. If the blower motor does not work, then purchase the resistor, it costs approximately $20.

The wires that connect the "fan settings" control knob to the blower motor resistor are held by a wire harness. This wire harness attaches into the back of the blower motor resistor. (Once the glove box is removed, this can all be seen by looking into the void, to the lower right.) This wire harness must be removed from, and prior to removing, the blower motor resistor. For me, it was very difficult to remove the wire harness from the blower motor resistor as it was basically stuck in the resistor and there is not a lot of room to work with. BE SURE to un-lock the red wire harness lock located on the bottom side (it can only be seen if you view everything from the bottom up) before pulling out the wire harness from the blower motor resistor. Once the wire harness is out, you can then work on removing the blower motor resistor. There are two small screws/bolts that hold the blower motor resistor in place. Unscrew/unbolt the two screws/bolts, one on the top left and the second on the lower right. You can then pull the resistor out and insert the new one. Install everything by reading the above backwards.