I am just now getting around to figure why the '04 Pacifica has no rear blower action for the A/C, the front works great. I took apart the center console and the only (2) wires that plug into the resistor mounted on top of the blower assembly are the wires that go to the motor. to the left of the motor wires plug, there is anothe plug that will have 4? wires that powers the resistor and runs the blower motor. I attached a few pictures to show exactly what I am needing to figure out. The resistor has the top cover removed in the picture...



Is the extra multi wire plug in the next picture possibly for a pigtail to the rear blower motor resistor? It is located between the middle seats at floorboard.



The last picture is to show a pulled back view to understand better. I have even looked for the other 3-4 wire plug up under the dash thinking a previous owner has issues and pulled them back or cut them off, but have yet to find anything.
I purchased the ALLDATA on the car when I had to get torque specs on the engine head work I done and the wiring diagrams are not drawing me a plain picture.

 

If the rear blower is not working at all, its probably that you need a new one(blower motor). Has for your extra plug, do you have rear heated seats? .

 

Thanks cirrus98,

No heated seats, and I removed the blower motor assembly and used jumper wires to the battery and the motor works great. I will see first if I can't maybe check one out at a salvage yard to get an idea. Maybe I can tie into the fan control for the rear blower motor that is between the 2 middle seats if it won't interfere with the normal dash controls.
I may just run a toggle switch as last resort since I won't need it very often as it's not the daily family taxi.

 

I ended up just doing a toggle switch and it cools the front and rear down quick on a hot Florida day!

 

the resistor is more then likely your issue

 

You are correct, since it has no wires going to it as shown in the first post w/the first picture. I searched as far back under the dash that I could and found nothing for the resistor wiring that resembled the wiring for the front resistor.
But the toggle switch is working great!