Hi,
Did you ever get around to the mode door writeup? I hope there is a way to do it without disconnecting the AC or heater core lines.

 

I replaced my mode door last weekend. not as bad as I thought it was going to be. Just follow ratlratls write up for the recirc door but pull the dash all the way onto the seat. Buy mode door kit and replace trying not to break the tabs that are on the back. if you have any other questions let me know. oh, in order to pull the dash all the way back you have to separate the main wiring harness by loosening the 10mm bolt in the middle of the plastic block.

 

How about the vent door? Do I have to remove the entire unit or can it be done just by pulling the dash back? From the pics, it looks like the vent door is accessible from the top of the unit.

I can't turn the dash vents or floor vents off (vent, mix, footwell positions don't change anything), but the defrost, recirc, and blend work fine.

If I do have to discharge the a/c and pull the whole unit, then I am going to replace everything that can break and do it all in one big swoop.

Also, why would the first, second and fourth fan speeds work, and the 3rd speed not work. If I turn it to speed 3, the fan stops. Dead switch or something else?

 

Its my understanding that there are only 4 doors in the hvac unit: Mode, defrost, blend, and recirc. Are you sure that you aren't talking about the mode door?

 

maybe it is the mode door.... It's whatever one that controls the dash vents.

 

yes that is the mode door and it can be changed without pulling the hvac box. just pull the dash back and you will have plenty of access.

 

cool! thanks for the response

parts will be ordered soon.

 

what do each of these doors do, and how much disassembly is required for defrost and blend?

 

no prob. if you have any other questions let me know.

 

Not sure exactly. I have heard to get to those doors you have to remove the entire hvac box which involves discharging the ac and unhooking heater core. once you have the box out you split it in half to acess the doors.

 

I'll start with this, which I have not validated and I am unsure of the accuracy:


the recirc door controls fresh air intake. when it is closed, air is drawn into the HVAC unit via the recirc air intake. when it is open, cold air enters from the outside.

the source air first passes over the AC evaporator and then to:

the blend door, which controls air flow through or around the heater core, controlled via the temperature control ****. air of the right temp then flows to:

the mode door, which directs the air to the floor outlet, vents, or defrost.

I can't find anything about a "defroast" door though....

 

Several have reported being pleased with just removing the recirc door by dropping the fan. Seems that unless you block off the opening in the HVAC housing where the recirc door would be when in the outside air mode, that the fan would blow a good portion of air through this opening in the HVAC housing which is normally blocked by the recirc door.

Am I missing something?

For those that have just removed the door, can you comment? Maybe, turn your blower on and feel that hole and report back?

My recirc door went today and I've got to do something. I have the Infinity radio system, so per RatlRatl, his fix won't work on my truck and the dealer wants $450.00 to fix it.

Thanks

 

Youp, missing something, but not a lot. The air "intake" for the fan is either fresh air or air from inside the cab. The recirc door blocks off either the fresh air or the cab (recirc) air, therefore, the fan would be sucking from the opening that is not blocked off.

The fan blows air to wherever the mode door tells it to blow. The temperature of the air is controlled by the door that diverts the flow through the heater core thus blending the hot air with the air that is not passed through the heater core.
Almost 3 years without a recirc door. . .

 

Thanks FMB. I'll drop the fan and pull out the door tomorrow. Maybe, we should start a new club called "Don't Need No Pinchy Recirc Door" club.

 

Excellent! Thank you. I was fearful that I would have to disconnect the AC and heater core.

Do you happen to have the part numbers for the mode door parts handy?