Car Tech forum: AC/Heating problems in 2002 Jeep Grand Cherokee

Yes I've seen this problem happen before. The heater core could be out or going. If your air system has a vent feature(blower off but warm air from the engine naturally circulates into the car), then a sticky valve can cause the A/C to seem warmer. But being a newer car, That feature probably doesn't exist. The AC unit might need refilled or bearings or something to that tune.

But back to the heater core thing, there are other things that go wrong with that. Since you get cool air from the A/C and no heat, it's obviously on the heating side. If the heater core is blown, it will often make your glove box flood or just be wet when it rains. It could also be a relay or heating coil problem. These things can easily be checked with a hane's manual and a fluke multi-meter($60 at most from AZ) But it could also be as simple as a broken connector or contact from the temperature control nob.

My personal advice is since the jeep's already in the shop, have them do a diagnostic, it'll be around $100. But don't let them rip you off with that $700 stuff. If they actually remove the whole system and test it, the labor costs won't be cheap, but $700 is pretty high. A completely new or refurbed A/C unit can be bought and installed for around that price. But it's only $30 for the do-it-yourself kit to refill the AC unit with freon. The heating system is a little more complex but if you're savvy with electrical stuff you shouldn't have a problem.

best of luck

You mentioned that somethimes the knob works and sometimes it doesn't. If the konb feels loose when it doesn't, then it's just a loose connector to the rheostat or ventilation controller. But the jeep people should be able to figure it out without too much difficulty.

Ask more questions or provide more info if you need to, that's what these forums are for.

Best of luck.

I AM LOOKING FOR GRAND CHEROKEE OWNERS ALL OVER THE US FOR A CLASS ACTION LAWSUIT AGAINST CHRYSLER CORP. THE MODELS THAT I AM FAMILIAR WITH ARE 1999-2004 GRAND CHEROKEE LIMITED WITH DUAL CLIMATE CONTROL. THE PROBLEM IS THAT NEARLY ALL GRAND CHEROKEE LIMITED HAVE THE SAME PROBLEM WITH THE DRIVER AND PASSANGER SIDE BLEND DOORS AND HEATER CORE LEAK. THE PROBLEM IS THAT THE BLEND DOORS BREAK OFF THE HINGES LIKE THINGS AND YOU HAVE NO CONTROL OF YOUR HEATING OR COOLING SYSTEM. I HAVE TRIED TO REASON WITH CHRYSLER CORPORATE OFFICE BUT THEY JUST BLOW ME OFF SO I THINK IT IS TIME THAT THEY PAY FOR ALL OF OUR HEATING AND COOLING REPAIRS. IF YOU ARE INTERESTED PLEASE GET IN TOUCH WITH ME VIA EMAIL AND THIS WAY WE CAN GET A BIGGER AND STRONGER NETWORK. MY EMAIL IS grandcherokeelimited@yahoo.com.

Indeed, there should be a suit; as to force a recall, further return funding to those who have received the shaft at the dealers.

I'm in the middle of fixing mine. I've opted to repair the blend doors myself, using super glue to reattach the broken parts, further epoxy and wire mesh to reinforce the weak areas. I'll try to post the procedure if successful, in that it's a repair that has a total cost of about ten bucks. Nevertheless, and in studying the design, a few things have become quite apparent:

First, the plastic shaft area of the doors has hollows -- two on each side of each door, which are there for no better reason than to create a weakness in the design.

Secondly, the hollow ends of the door shaft, where the white plastic parts slide in, are only about 1/16 of an inch thick along their length where the door its self attaches. This is an exceptionally weak point, further where most of the first, inner doors break. It will crack straight through this area and terminate at the aforementioned hollow in the shaft. I suspect the crack begins at the hollow, then merely snaps through the 1/16 of an inch area once the hollow gives way.

Third, the aforementioned end, where the white shaft enters,is also quite weak, in that the second door typically breaks this end in half; thus, P-poor quality of material used.

Fact is, nearly all the doors break in the exact manner described here. And if Chrysler didn't design them to, then tell me why there exist the need to have fault codes which state the travel on these doors is too far? They can't go, "too far," unless they're broken! The fault code should simply be translated into, "The blend door is broken."

Therefore, I'd say that the evidence shows intent; furthermore, the lack of an access panel, resulting in a dash removal and near two thousande dollar dealer repair, shows malicious intent; thus, damages for pain and suffering are further likely in a suit; especially if you live in a cold climate.

Like most of you, I don't have dollars growing on my trees or falling out of other places. Therefore, when that annoying service notification comes on, I don't go running to the dealer. I merely keep my oil clean, further reset that milage setting on this notification to keep it quite. However, Chrysler clearly has other ways of getting to you; in that it has progressed to my check guages light coming on periodically, followed by the oil pressure guage dropping to zero for a spell; thereafter, the light turns off and the oil guage goes back to normal.

Anyone with a brain knows that oil pumps are mechanical. They either work or they don't. There's no middle ground. Therefore, it's a scare tactic, further programmed into the system to get you to take your car to the dealer and drop a mint. Furthermore, this too is quite obviously malicious and fraudulent.

There also exist a wide spread problem with the ignition lock. Most will tell you that dirt or lent gets in and you have to tap the end of the key to get the tumblers in place; however, and having actually removed and serviced the existing lock myself, I discovered an interesting fact. The inner end of the lock has a plastic part which the key pushes over to sound the chime when inserted. Somewhere along the line, this part is binding, further causing the key to not be inserted far enough to align with the keyways; thus, you can't turn the key to start the car.

The dealer will merely replace the lock, further charge you a mint to reprogram the keyless entry and transponder key; however, the true fault exist within the series of components associated and working in conjunction with the lock. There exist a mechanism which locks the shifter, followed by the ignition component its self. Be it within one or the other, its causing the illusion of having a faulty lock. It doesn't happen continuously either, in that it happened to me about four times in five years. And this past week is when I finally took it out and made the discovery.

A special note. For anyone who has ever experienced a problem with the electric window malfunctioning, I have a solution that only cost about five bucks. It's likely that the braided, bicycle like cables they use has freyed and bound within the mechanism; therefore, if you take it apart and discover this to be the case, you only need go to K-mart/Walmart and get a ten speed bicycle cable, remove the braided part from within the sheath, and use it to make the repair. My repair has lasted for three years so far. You'll need to be creative with attaching one of the ends, such as using an allen wrench lock designed for hat pins, or perhaps some jv weld; however, it's doable.

Chappy905;

I'd sue the dealer for the expense of having an oil pump replaced that clearly wasn't required. Like I said; oil pumps either work or they don't. And if yours was broken, I can most certainly guarantee that you wouldn't have made it to the dealership. As for "THE FIX" of the blend doors, I'm going to tell you and everyone else who runs across this post how I did it.

First of all, start the car and then hold both the recirc button and ac button down at the same time; then, turn the driver's side temp button one click to the right (clockwise) and let off all buttons. A series of codes will flash and continue to repeat upon the display. I believe broken door codes are 22 or 54 for the driver's blend door, and 24 or 56 for the right. To be sure, however, open your glove box, remove the support arm on the right, and muscle your door the rest of the way down. And no, mine didn't break, in spite of the numerous times I ended up doing this. Remove the two screws that hold the motor located at your left. If you can freely turn the white plastic tab beneath the motor without it stopping, your blend door is broken. The left door, unfortunately, can't be checked this way that I'm aware of; less you're Tom Thumb.

If they're broke, you need discover where to cut the panel behind the glove box. I see no way of posting a picture here, so I recommend clicking on the following link for a picture and procedure of the cut area:

http://www.jgcparts.com/JGCParts_Jeep_heatertreater_International.html

The aforementioned link is where you can buy the repair kit, so I hope the person who sells it doesn't mind. However, and if every penny counts, then I'm going to tell you how to fix this problem for about ten bucks.

In the picture showing where to cut the panel away, you might want to move the vertical cut on the right over towards the left about two to three inches. A large hole is not necessary to remove/install the blend doors, and their illustration has you cutting dangerously close to the A/C evaporator. And if you damage it, you're screwed.

I used a dremil with a very small, circular saw blade at the end of the bit. If you're strapped for cash and don't have a dremil, you can use a power drill and the drimil bit in question. You can get the bit at Walmart for a few bucks. Just remember to cut at an angle, as to give the peace you're removing some backing along the cut to sit against when you reinstall it. A decent quality roll of duct tape works quite well to seal it later.

CAUTION: You'll notice that there's a screw tab in front of the part you're removing, where the motor attaches. If you don't make complete cuts, you might snap this off. Therefore, don't try to force the peace you're removing if it's still attached in some places.

Now that you have that peace removed, you'll need to make one vertical cut within this area to remove the center, plastic divider between the doors. Cut downward until you get to the area where the axis of the doors are held in place, then remove it. It's sitting in a grove along the bottom and need not be cut through this area. Once you've removed that section, you can easily lift out and remove what's left of your blend doors.

CAUTION: If it already hasn't happened, parts of the door may have fallen down inside. Remember that your blend doors are likely not in one peace. Remove them carefully, as to not allow any peaces to fall down within the compartment; you'll be needing them. One peace fell down on mine, but I was able to recover it; therefore, carefully give a search down in there if anything falls.


Now for the really fun parts. You'll notice that the pads on both sides of the blend doors are covered with a nasty, sticky mesh that was once your blend door pads. You can remove most of it with your fingers; however, you'll likely end it with a small, wire brush. Get it all off! Don't worry about scratching up the doors; they'll need to be roughed up pretty good to hold the epoxy you'll use later. Also make sure you've washed them up really good with soap, as to remove any dirt.

Now that you've managed to clean them to bare plastic, examine your broken areas. Test fit these areas to be sure you're able to get them meshed back together tightly. Then, take a generous amount of super glue (I used Locktite super glue), and glue the broken parts back on. Be sure to get a nice, snug fit, hold them together for a spell, then let them set for a while to completely dry. Thereafter, take some 50 grit sand paper and rough up the entire area; from one end of the shaft to the other.

You'll now need some decent epoxy. I used a tube of locktite plastic epoxy I got from Wal-Mart for about three bucks. You'll also need some wire mesh. You should be able to get some at an auto parts store; the type and kind used for automotive body repair, as to hold bondo. It comes with an adhesive backing.

I cut the wire mesh just wide enough to cover the large part of the shaft; the part which likely broke in half or completely off; as it did on mine and likely yours. Cut it so that it is about three inches long, as to assure it goes up both sides of the door at least an inch, once you wrap it around the hollow portion of the shaft. Use some pliers to assure the mesh makes contact over every area upon which it covers. If you don't have the type which adheres, or if the mesh doesn't adhere because the plastic is too rough, then simply use a clamp or your fingers to hold it down while applying the epoxy around one part, then apply more once the previous dries and holds it down for you. You'll need some cheap, water color paint brushes to apply the epoxy (Walmart, $1.50). I also recommend some cheap plastic gloves.

Once you're ready, put the epoxy on a peace of cardboard or the top of a coffee can lid. Mix it quite well with the plastic end of the paint brush, then use the other end of the brush to apply the epoxy over the wire mesh. Use a generous amount of epoxy as to completely fill and cover the wire mesh. Also use a bit of epoxy to fill those two voids along the shaft on each side. Might as well make it stronger while you're at it, right?

The epoxy takes less than seven minutes to set; therefore, try to work quickly. I mixed enough at a time to make a fifty cent peace sized pool of it. If you run out before filling the voids, you can always mix a bit more after the fact. You can also work the epoxy a bit with your fingers after it sets. It takes quite a while for the epoxy to really harden, so make sure it does before taking any steps hereafter. At this point, the repair should be more than strong enough to work. Nevertheless, I took it a couple steps further.

I cut a small peace of fiberglass cloth; also available at the aforementioned retailer, and cut it wide enough to go from one side of the door to the other, further over the area you just repaired. I mixed some epoxy, quickly applied it to both sides of the door and around the length of the shaft, and then quickly placed the cloth first around the shaft and then up both sides of the door about a third of the way. I continued to work the cloth against the doors with the brush, all the while applying more epoxy to build up the amount of it upon the cloth. Don't freak if the cloth doesn't want to stay against the door; it will if you keep working it. Just make sure it conforms to the entire length of the shaft, especially the area where it meets the door panel. Don't be concerned about building up, too much epoxy; there's plenty of room where the door shafts rest within the compartment.

Note: make sure you sanded the first coat of epoxy from the wire mesh application. It will need to be rough for the next coat to properly adhere.


The reason I used the fiberglass is because the shaft area, where you made your mesh repair, tapers down to the smaller diameter of the shaft. The wire mesh simply isn't flexible enough to conform through that taper.

Now it's time to apply some new padding. Once again, Walmart served its purpose. They have some padding used for home ac/heater filters. It's about a quarter inch thick, and it cost a buck! Cut it to the size of your doors, and glue the sucker on; one for each side of the door of course. A tad more epoxy along the edge should do fine to adhere them. Thereafter, just trip the excess with a pair of scissors.

Note: Don't push too hard when gluing the pad on. You might soak the pad and cause it not to be even across it's surface. Simply flip it over and gently hold it down on the table to evenly adhere it.

When you try to put it all back in, you'll likely discover that the back door wont slide over the white plastic insert . You'll have to either adjust the right temperature dial to make it move, or do as I did in the following procedure:

Start the car and turn your dials to automatic on the heater/ac control. Turn off the engine, pop the hood, and open the fuse box next to the battery. Remove the 50 amp fuse #15 for two minutes. Then, reinstall and start the car. Be sure you're ready to install the door by holding it in place over the white plastic shaft before reaching over and starting the car. You should feel the door ultimately slide on the shaft once it starts turning. Then quickly set the doors into the center slot and shut off the car. You might also need to do the same when putting the front motor back on, too. The aforementioned procedure, bye the way, is what you'll have to do to get the motors calibrated once the install is complete. However, let the car run for two minutes to let the cycle process. You can watch your doors functioning during this time, further making sure that your repairs were worth the effort. Thereafter, tape the removed panel back in place, shove the glove box back up and reattach the glove box arm on the right. And yea, I just forced the glove box down to get to the area. It didn't break anything, in spite of having done this several times. Just make sure you disconnect the arm that holds it on the right before doing so.

It's been nearly a month now, and my blend doors are still working like new. Hope this helps you folks out there suffering this problem.

I'm having this problem in my Jeep as well - not great considering that my son's carseat sits in the back passenger seat, we live in Iowa, and winter is definately here! Essentially, the passenger side blower works fine, but it is blowing cold air regardless of how the passenger side thermostat is set. I can't let anyone ride with me, because I can't close the vents enough to keep cold air from blowing on them, never mind how uncomfortably cold the backseat is for my son! It is incredibly uncomfortable. I've copied your post outlining how you have fixed this issue, and will forward it on to a friend that I'm hoping will be able to help with this issue. He looked at it quickly one morning for me, and said that there was no way to access the passenger side without pulling the whole dash - did you find this to be true as well? Will he have to pull the entire dash in order to do this fix?? That's my main question... I know nothing about cars, and am hoping that your description will guide him to a solution, but if he has to pull the whole dash, that's concerning..... Let me know what you think.

The pictures in the aforementioned link are for a right hand drive Jeep. Don't let in confuse you. Yours will be the exact opposite of theirs; less you're in England.

Hi there I have a jeep Cherokee 2003 4.7 when I put the heater control on Hi it comes out cold and when on low it comes out hot can anyone help thanks

I have the same problem...It heats on the passenger side but its cold on the driver side...I did the test by pushing the 2 butttons and got error messages 52, 24 and 54. I am all for the suit... tharas@cox.net

ive had every single one of these problems!!!! ive sent alot of $ repairing it all and now working on the ecm being replaced cuz diagnostics says its bad, oil pressure gauge reading as high at all time times and getting my ac fixed for the 2nd time cuz the 1st time it wasnt fixed correctly!! im very interested in being reembursed forall these cost- i bought the vehicle 3 mths ago so on top of the repairs im paying mouthly payments!! very frustrated!!

I just purchased a 2004 Jeep Limited-I think I have heater problems and there were numerous postings about a potential class action law suit. OR creating enough pressure for a recall. What is up? Thanks BOB

Your email address did not work.

So, what happened with this? I sent you an email a few weeks ago and never got a reply.

You may just need an AC refill.
I'm still trying to decide on either taking the dash out or doing it through the glove's compartment.
I just think jeep should be taking care of this since it is an engineering flaw design. I own an old 1994 nissan which heater still works amazing.

I live in the UK and have just bought a Grand Cherokee Ltd 2002 knowing that the drivers side heater didn't work.

My husband and I travelled to Orkney on a 5 hour drive starting at 6am on a cold February morning and returned on a cold February evening the driver wearing 2.5tog socks and wrapped in a blanket!

We checked with our local dealership in Aberdeen, Scotland and was told it would be £1,300 to repair.
We chose not to have it repaired.

My husband, not to be beaten, arrived home yesterday evening with a plug in to the cigarette lighter heater costing £20 and placed it over the hole where the cold air blows, The cold air still comes into the drivers well but mixes in with the hot air from the little heater - quite amazing!!

Not, I admit, an ideal solution but my husband, a canny Scot, has solved a very expensive problem quite cheaply!

Link below:

This isn't the one we bought which had attachment fittings but it shows the type of heater we bought.. Hope it helps.

http://www.ebay.co.uk/itm/UNIVERSAL-12v-CAR-HEATER-PLUGS-CIGARETTE-LIGHTER-NEW-/120349548101