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I bought a 2011 Grand Caravan last November, maybe that was my mistake, buying in the winter.

It has the dual climate control (one driver, one passenger) and a rear control as well.

Fast forward to a couple of weeks ago and this terrible winter is finally letting up. We had a few warm days and turned the heat over to cold on all three knobs only to notice that the passenger side and rear vents were blowing hot air. With the AC on the drivers side does blow cold, but the passenger/rear is always hot.

One additional note: under the driver's seat is a large wiring harness connector that shorted out due to the wet/salty water from the winter. So the driver's seat cannot be adjusted and the seatbelt sensor doesn't sense. I only add this in case the wiring could be causing the vent motors to stop working (but I kind of doubt it).

I'm handy with tools, but I'm not a mechanic by any means. I'm planning on fixing the wiring under the seat soon. Do you guys think that will fix the HVAC issues or am I going to have to tear open the dash? If it's not the wiring how do I fix this?

The warranty is over.


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I would bet the problem is blend door motors being bad, but don't know how Dodge does their thing here. – Pᴀᴜʟsᴛᴇʀ2 Apr 16 '14 at 12:35
I had a similar issue last year. In my case the passenger side vents were blowing heat. At the end of summer I heard the internal vent slap open or closed and cold air started to come out. This year, it's doing the same thing again but a little different. It's the rear vents. – user10165 Apr 18 '15 at 4:46
up vote 2 down vote accepted

It sounds like maybe a bad passenger zone actuator in the HVAC controls causing the issue up front. As for the rear, that could be another actuator. I think there is a separate evaporator for the rear, it could have a clogged expansion valve or a leak. If it's leaking, you should lose the front A/C fairly soon.

I don't think the seat wiring has anything to do with the HVAC issues.

To get at the HVAC bits, you're going to have to remove your dash. There are some videos on Youtube. Don't forget to disable the airbags if you value your life. If you do it by disconnecting the battery, don't forget to wait for the backup to drain (enables airbags to deploy in crash that severs battery wiring).

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Wow, excellent information. I'm repairing the wiring this weekend. While I'm in there I'll take a look at the dash to see what I find, but that certainly sounds like a big job. – John the Ripper Apr 17 '14 at 0:44
I don't find dash removals difficult, just tedious and time consuming (hunting for fasteners you missed is fun). You have to take notes/pictures to make sure you got everything back where it came from when you put it back together. I find it helpful to have different small bags for the fasteners that can be labeled as to where they go. Go slow and be gentle and you'll be fine. I wouldn't try it unless you could budget at least one whole day for it. If you want some practice, visit a pick-n-pull and take apart a similar vehicle. As an added bonus, you'll have spares in case you break something. – Mark Johnson Apr 17 '14 at 17:06
I fixed the wiring under the seat this past weekend so now the seat is adjustable again and the seat belt sensor works. One new symptom I notice now is the rear window defrost/mirror defrost button is flashing. From some internet searching it appears the HVAC is trying to calibrate due to battery terminal removal. Can this flashing/calibration have something to do with the HVAC issues? How do I stop the flashing? Thanks – John the Ripper Apr 22 '14 at 16:06
Did you disconnect the battery? If it is trying to calibrate and you have a faulty component it may not be able to complete the process. Hopefully it will give up at some point. It might be trying to flash some kind of diagnostic code to you. Do you have automatic climate control? – Mark Johnson Apr 22 '14 at 16:31
I did in fact disconnect the battery, but I do not have Automatic Climate Control. As I said before though I am going to pull the dash apart in 2 weeks time and we'll go from there. You've been very helpful. – John the Ripper Apr 22 '14 at 17:42

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