Ford BLEND DOOR FIX (EXPLORER, RANGER, EXPEDITION)
If your climate control only has two settings: HEAT and MAX A/C then the chances are this fix will work for you.
The fix was originally developed by FTE member jfranks � YOU RULE!
I paraphrased the blend door fix from jfrank and added some digital pictures I took when I completed the fix on my 1996 Explorer. His original fix document is available here: jfrank's blend door fix
Remove the glove box to gain access to the plenum. There is a release on the left hand side of the glove box.
Locate the actuator. The actuator is a flat white box that sits on 4 clip posts on the top left of the plenum. It has a wiring harness coming out of the front.
Remove the actuator. Use a flat head screwdriver to pry up the actuator. Pry up the front first and then put the screwdriver under it to pop up the back. (Note: I unplugged the wiring harness when I removed mine. If you also unplugged the wiring harness you will need to plug it back in before doing step 4).
On the bottom of the actuator there is a �D� shaped pin. Turn on the ignition and move the heater control on the dash. You should see the pin rotate (wiring harness must be attached!). If the pin does not rotate then you have a different problem (bad actuator, terminals corroded, etc). If the actuator does move, set the heater control to full heat and turn the blower on high. THIS IS VERY IMPORTANT. It moves the actuator to the correct position for the fix.
Actuator "D" shaped pin.
Using a small dentist mirror and flashlight, look into the top of the box where the actuator pin goes. You should see that the chamber is half missing. It should look similar to the drawing below:
They all break roughly in the same spot. If it looks like the drawing above then drill a hole (I used a 1/16 in drill bit) in the actuator pin in the location in the drawing below:
After drilling the hole insert a metal rod. I used a cut down finishing nail. Others have used a cut down drill bit. Be sure to have about 1/8 in on either side of the pin. Be sure it is snug in the hole.
Close up of fix. Drilled out with 1/16 in drill bit and cut down finishing nail.
Close up of fix - side view.
Snap the actuator back on the box. If the pin won�t go in fully then the rod may be in the wrong place. Remove the rod and re-drill the hole. Reinsert the rod in the new hole and try it again. You may need repeat this step several times until the actuator fits.
Once the actuator fits back in the box, try the heat controls. Go from heat to cool. If the temperature changes, Congratulations! You just saved yourself $1000!
(Optional) Take the actuator back out and put a spot of glue on the rod to keep it firmly in place.
there are pictures at http://www.blenddoorfix.netfirms.com/
The root cause of blend door problems on the Explorer is the motor overdriving the plastic blend door and eventually breaking the door. Once this happens, you lose control over temperature control of the HVAC system. Replacing the plastic door with another plastic door is a temporary fix...the door will break again over time. The HeaterTreater solution replaces the plastic components with steel that will outlast the Explorer, and is installed with a greatly simplified process of accessing the door by making a Dremel cut in the bottom of the heater box(no disassembly of the dash panel whatsoever). The fix is very easy and 100% effective. Check for more information at www.heatertreater.net, or by clicking on the Google ad on this forum.
That's controlled by the blend door, not by a fuse.
If the defroster is blowing hot air and it is still leaving moisture on the inside of the windshield, the heater core may be leaking coolant causing that condition. If the defroster is blowing cold air it could be the cooling system is low on coolant, or the thermostat is stuck open or the heater core is plugged up or the temp blend door has a malfunction.
There isn't one. There'll be a fuse for the HVAC blower, but the heater itself doesn't use electricity (other than the blower fan). That year Ranger should have cables going to the blend door, so there won't be electricity there.
how to replace a blend door actuator on a 1999 ford ranger
The blend door sits vertically in the heater box behind the glove box. If you fully open the glove box, you can see the actuator motor on top of the heater box in the upper left hand corner. On the bottom of the box is a "pedestal" that is the bottom axle point for the blend door. The door axis is between the motor axle and the pedestal. If you are having issues with a Ford Ranger blend door, you can find diagnostic procedures with pictures and a cheap easy solution to the problem at HeaterTreater www.heatertreater.net, or follow the Google ads on this site. cgallen
Either the Heater Control Valve is not opening or the BLEND doors aren't opening BOTH could b due 2 a Vacume leak going 2 either one.OR the heater core could b blocked.
I think your refering to the door in the heater housing that directs air to vents, floor or defroster vents, there is also a blend actuator that mixes heated or cooled air to give the correct temperature from the selector.
The heater blend door is not run by vacuum. It is run by an electric actuator.
Most temp blend doors have an electric actuator. The defroster, dash vents and floor vents are usually run by vacuum.
If all you have coming out is cold air it is probably the blend door control. The blend door sits directly behind the heater controls. It is a square white plastic box (3in x5in and half inch thick) It attaches to the slide control from cold to hot with a small screw type gear (plastic) and strips out VERY easily.See "Related Questions" below for more
How do I locate the heater blend door actuator in a Ford f150 pickup
Sounds like the heater control valve. It could be the blend door actuator motor,which is located on top of the heater housing. this is what controls the fresh air flow through the heater.