Hello sportsprint,

It always helps to give more details such and year, model, engine, etc..

I have a 2014 factory service manual (FSM) CD (available <$100 on line) that covers the HVAC system pretty well.

I will attempt to get you started on this. I've been searching for online info about Patriot/compass/Caliber diagrams of HVAC, blend door, blend door actuators but haven't hit gold yet. Try a search yourself.

This Jeep Cherokee thread has some excellent information from "Jeep Cares":
http://www.jeepforum.com/forum/f292/...-work-2009553/

This diagram from the thread is EXACTLY the same as the one in the Patriot FSM:

The Patriot FSM lists 3 actuator MOTORS: 1 for the blend door (3), 1 for the outdoor air/recirculation door (5) and 1 for the mode door(s) 9 and/or 11.

The blend door actuator motor is on the left of the HVAC assembly where the drivers right leg would be, under the dash. The other 2 actuator motors are on the right, passenger side of the unit. All visible looking in the footwell areas and easily accessible.

The FSM warns to disconnect the battery/airbag system first and says that the HVAC controller has to be recalibrated any time an actuator motor is replaced.

All three blend door motors are the same and interchangeable. They are relatively cheap: https://www.google.com/search?q=jeep+patriot+blend+door+actuator&ie=utf-8&oe=utf-8

This is what you are looking for on the drivers side: there should be two, maybe three on the passenger side.

Diagnostics is half of the problem. Your controller might be bad, sensors might be bad. Don't overlook the obvious: fuses, etc..

Hope this helps.

 

Treegrower. Good name. I also am growing some trees. I posted this above before, spent a lot of time writing this post, then got a reply to take it to the dealer. Not what I want to do.

To describe this problem better, I have a 2009 Patriot 2WD with larger engine. I also have a 2012 Patriot the same. This gives me "swapping power" should I need it.

The 2009 came with no filter in the cabin air vent. 100,000 miles. I bought the Jeep used, found the filter absent, then added the filter.

I bought this Jeep in Sept. Most riding has been with the A/C running. All seemed fine. Nice and cool. If it got too cool, I can turn the knob and I can add a little warmth.

Then, it got cold. We started to use the heater. Since I drove the 2009 mostly, everything seemed fine. From the drivers side.

A couple of weeks ago, my wife rode with me. She said she was cold. My vents were nice and warm. Then, she shut her vents as she said it was cold air blowing on her.

I reached over and opened her vent to the far right. It was blowing cold air. The two center vents were warmer with my side being the warmest. The left vent on the driver's side was nice and warm.

We do not have any "zone control" that I know of. My thought is some vent door might be sticking. Or partially not closing. Maybe the fresh air vent.

Anyway, this problem is still going on. The engine temp gage is fine. The radiator is full. My side of the vents is nice and warm. I can turn the knob and cool mine down, if needed. So, that works. But, my poor wife's side is freezing!!

Hope this helps. I am hoping the problem is at the passengers side as I can get to that a LOT easier.

B DeFeleciantonio

 

O.k. I probably cannot help anymore. It does seem that you are getting heat from the engine/heater core system and that something is wrong with the ducting system.

I poked around in the diagnostics section of my FSM a bit, but could not come up with your exact problem: cold air blowing out of right vents with heater on.

the diagnostic sections cover: insufficient coolant temp from engine (you imply this is o.k.), bad temp controller (you say yours works), and mechanical problems:
•Obstructed cowl air intake
•Obstructed heater system outlets
•Inoperative engine thermostat
•Inoperative blower motor system
•Inoperative A/C-heater control
•Inoperative blend door actuator
•Inoperative, obstructed or improperly installed blend-air door


Does your defroster vent blow out hot air? Is the air on the passenger side the same velocity/volume? I was thinking maybe its as simple as a mouse nest in the duct system, but this doesn't apply if air volume is the same, but just cold.

The FSM does have a very long diagnostic process to evaluate HVAC DTC (OBDII codes) that are tripped when the controller/computer/duct doors do not work properly. So, you might want to check for any HVAC codes as a starting point to help diagnose your problem.

Sorry I can't help much more. I have no direct experience with the inner HVAC workings and am just parroting FSM info. There are two Caliber threads with the same problem, but they don't follow up with a resolution. The only Patriot thread I found with a resolution said the problem "improved" by closing the recirculation door, but that might imply that the heat exchanger (coolant related) maybe wasn't putting out enough heat (partially clogged).

 

It ended up a partially plugged heater core. Replaced it. Thanks for the great write ups!!

 

Hey there, its good that your problem was fixed. I was also having similar problems, then my friend suggested me to consult a NJ Heating & Air Conditioning Contractor technician and seek advice from him whether the system needs to be repaired or replaced.

 

I experienced a similar problem years ago while living in the "hot" country, where we hardly ever used the heater--core clogged--VERY expensive repair. So: remember to cycle ALL those vehicle systems periodically...

 

Excellent reminder there, Jack, to exercise your controls every now and then. Just last week I needed some rare summer heat to defrost some humid interior window buildup and it took a few attempts for the heat to kick in, like something was stuck. Everything is working fine now.

Regarding heater cores, I learned from my daughter's troublesome Taurus with chronic heater core plugging that they can often be flushed in-vehicle to get them operating again. Lots of You-tube videos on the very simple procedure:

.

Take care, everyone. Enjoy the autumn.