Late spring sometime the heat in my 2003 Dodge caravan went out. After letting it go for a few weeks I started some research and found several trouble shooting web sites like the link below and I was able to determine the blend door in my van was broken. The blend door actuator (motor) tested good, but the shaft it connected to on the heater box was loose inside the heater box. When turned, the shaft sticking out would catch a little bit, but then would continue to turn a round and around, it should only turn a quarter turn or so. So I knew the shaft was no longer connected to the door.
I googled and googled and all the posts I could find on how to fix the issue involved removing the entire dash from the van, or paying someone else in excess of $1,500 to do it for me! And since I paid slightly more than 5 grand for this van a little more than 5 years ago, sinking 1500 bucks into it didn't seem like a good investment nor something I was about to do. And the idea of removing the entire dash was too overwhelming for a weekend project. This Van is my daily driver after all.
So I spent a little more time looking online for a different fix and hoping to get an idea of what the heater box looked like inside and what the blend door that was broken looked like with hopes of finding a different way to fix this problem.
So I spend the summer without heat, which in Michigan this year wasn't too bad. However, as the weather started turning colder I started searching again. There's no way I want to try to get through winter without heat! In my searching this time I even made a trip to the local junk yard hoping to get some ideas, but didn't have any luck coming up with any. And I still couldn't find a fix or anything else to try, then I came across this post on flicker of someone who had gone through the process of removing their dash to fix their blend door the correct way...
In his posts he had the first picture of the broken blend door I could find and He provided some great information about the replacement process. Namely that the blend door was not sold by itself, but rather the whole heater box assembly was sold as one unit and that whole unit had to be replaced to fix the problem. Well that told me I had nothing to loose. I had no heat and the fix is to replace the whole heater box that contained the blend door... So cutting into the heater box would cost me nothing as the whole thing would be replaced if I couldn't fix it and had to go the "correct" route to have it fixed... I started by cutting out a square slightly larger than the shaft opening around the shaft of the blend door in the side of the heater box by the drives side petals. Originally I did this with hopes of fixing the broken door in place. But once I saw the broken shaft first hand I knew it wouldn't be easy to glue or repair the door and a replacement door would be in order... So I cut a slot in the side of the heater box big enough that I could slip the whole door out... Then I decided to visit the junk yard again. As I mentioned before I had been there earlier this summer trying to get a better look at the blend door in a 'broken' van with no success. But having already visited the same junk yard I had just the van in mind to get a replacement door from. The van's dash was already mostly destroyed or removed by other people making for easy access to the heater box. I 'carefully' removed the blend door from the heater box, with a tire iron I found in the van. When I got to the desk to pay for the blend door the gentleman at the check out asked what it was and when I told him it was a blend door for a caravan he said it looked like "free" to him... So I left the junk yard only having to pay the 2 bucks it cost for admission to the yard.
When I got home I put some white lithium grease on the ends of the blend door and slipped it back trough the slot I had made in the heater box. Using some gorilla tape I taped the parts I had cut out of the heater box back over the hole. When the blend door is put back in, it falls to the coldest setting by default. So, I turned the van on and made sure the heat was set to the coldest setting and then installed the blend motor again. I tested the motor alignment by changing the heat as hot as it would go and back to cold again and I could hear the door moving as designed and stopping where intended. Now I have heat in my van once again!!! And it only cost 2 bucks to fix!
Step 1: WIsh I had better pictures...
If I had to do it again I'd; a: take better pictures so I could explain this better... b: I would make a single cut out part so there would be a good piece to put back over the hole I made. But when I started out I was just hacking and hoping... which left me with a lot of small parts.
I used my Oscillating cutter/sander from Harbor Freight with the blade it has on it in the picture to make the cuts in the heater box.
The red rectangle shown in the picture is the approximate area that needs to be cut out to remove the blend door. You can see from my picture that the hole I made was not so nicely cut out.
***You will need the part you cut out around the shaft to put back to keep the shaft in place. So make sure you cut around that carefully! Thankfully I thought that far ahead when I started cutting. Also, be sure when cutting NOT to remove the whole stand behind the blend motor that provides support to the motor, see picture.
Feel free to contact me if you have questions and good luck fixing your blend door for a fraction of the work and cost of doing it the 'correct' way!
And remember this is a 'hack fix', no grantee how long it will last... but it could save you 1500 bucks or more!