Wrangler Blower Motor Resistor Block Replacement

Mopar Blower Motor Resistor Block

So yesterday I got into my 2004 Wrangler and the fan wouldn't work correctly. The fan would only work on high, but the other 3 settings wouldn't work whatsoever. I ended up Googling the issue. When the blower only works on high, it means that the resistor block has gone bad. Since the resistor is only used for the lower setting and the high setting is full on, it is the only setting that will work since the resistor block isn't being used. I don't know if you have ever driven with the fan on high in your Wrangler, but it is extremely loud and distracting. It is an easy fix though.

After doing a little research online and finding great videos on how to change it (see below for the most descriptive series) I decided to do it myself instead of taking it to the dealership. The Motor Blower Resistor Block is quite cheap. I bought it from my dealership for a mere $17 after taxes. It took me about an hour to install it, as it was my first time. Now it works like it always did.

Required Tools

• Phillips Head
• Small Ratchet with appropriate sized socket (a 9mm worked well for me, test first)
• Small Flathead
• Flashlight

Steps

1. Disconnect Battery (likely need an adjustable wrench, remove positive terminal, red)
2. Remove Glove Box (remove strap from slot and lower to remove)
3. Remove Floor Light (with Phillips head screwdriver, put aside or disconnected from cable harness)
4. Unscrew two bolt holding the Resistor Block into the ventilation system using the ratchet and socket (it's in the ventilation system because it gets hot!!)
5. Remove carefully downward, its gonna be awkward to work on
6. Remove Resistor Block from Cable Harness (TIP: Remove the red tab using a small screwdriver, pry against bracket to get it out if it is stubborn and work it out of the cable harness, it will be difficult but wiggle it side to side and it'll come out)
7. Carefully put in new Resistor Block and bolt into place (can put it in from the top without attaching it to the wire harness first)
8. Attach Wire Harness
9. Reconnect Battery
10. Test
11. If all goes well and the fan now works on all settings, put the glove box back in and remount the floor bulb into place

Notes
If the resistor block replacement doesn't fix anything, you might have a bad resistor block or there could be a short in your fan speed selector knob.

Videos
The following video series was the most helpful video I found online. It will be invaluable when you try to do it yourself. It isn't too hard at all to do.