1993-2008 Ford Ranger - Heat and AC Blend Door Replacement Parts
This is a product developed by the HeaterTreater Engineers for the
common blend door failure problem on 93-08 Rangers. Please
check our feedback to get an idea of the product line integrity and
customer reaction to our products. We are committed to customer
satisfaction and successful repairs of blend door problems.
The
HeaterTreater replaces the plastic blend door with steel. Replacing the
existing door with another plastic door is at best a stop-gap solution.
The failure is a result of excessive forces in the operation of the
blend door. Modifying the top or bottom axle contact points will
further weaken the system and result in faster failure of plastic
components.
Replacing
the plastic door is only solving the symptoms of the problem. The same
system design problem that caused the failure in the first place WILL
re-occur over time. The HeaterTreater attacks the root cause of the
failure by constructing hardware that is designed to meet the rigors of
normal operation of the HVAC system, and last for the life of the
automobile. The kit includes detailed instructions and all
hardware required to complete the fix, including dremel bits and metal
tape to seal the cut.
This
is a kit to do a complete repair on the blend door malfunction that is
common to 93-2008 Ford Rangers. Every Ranger in this
range either has, or will have, this common failure. The pictures
show the hardware provided for the fix. All work is done through
the glove compartment opening and a Dremel cut in the bottom of the
heater box...no removal of the dash panel or evacuating the AC system
and draining the radiator. Once completed, the alterations are
under the dash panel in the foot area and are not visible. The
work to install the fix is relatively simple and can be accomplished by
the average shade tree mechanic. The work could easily be done by any
local independent garage. Product returns are accepted within three
weeks for a full refund(minus shipping).
The
standard fix for the blend door failure is to remove the heater box and
replace the plastic door. If the instructions with other fixes start
out with “remove the heater box or dash
panel�, be ready for considerable work. Removal of the box
requires removing the dash panel, evacuating and disconnecting the AC
compressor, draining and disconnecting the heater hoses. Fixing the
door is relatively easy, but the labor(and cost) of getting to the door
makes this a time consuming and expensive job. The HeaterTreater avoids
the hard work by providing a kit that allows the repair to be done with
superior components without having to disassemble the automobile. 1hr
work vs 8-14 hours of work, and no specialized mechanical skills
required.
The Problem:
-
The Ranger is built with a Blend Door to control the heater and AC
function. The blend door controls air flowing through AC
evaporator and diverts it into the vent system or through the heater
coil, or any combination in between. The doors are controlled by
a stepper motor. The issue with the system is that the system has to
calibrate itself and find the end points of movement before the
computer can understand the two closed positions and regulate the
temperature. The photograph shows the blend door actuator motor
for the Ranger. The fan gear is connected to the blend door and the
motor is capable of moving the fan between the constraints of stopping
against the motor case. The fan is a 90 degree fan. When it moves
between the two stop points, it has 90 degrees of movement
capability(180 – 90). The motor is capable of moving
the door through a 90 degree arc, but the door hits the extents of
movement at 50 degrees. The net effect is that the plastic doors have
to absorb the force of the motor driving to a stall point. The
motor is geared to move the doors slowly and with a good amount of
force. The door has to withstand the force of stopping the motor, and
like bending a coat hanger back and forth, will eventually break.
Do you have the problem?
The
usual symptom is an inability to effectively control the temperature of
the HVAC system. The door hangs on a vertical axis, so turning a sharp
corner, or fiddling with the fan speed can swing the door into the hot
or cold position randomly. While the symptoms are fairly conclusive for
blend door failure, the only way to really check it out is to remove
the blend door actuator motor and look at the axle.
You
can access the actuator motor by fully opening the glove box(squeeze
the sides of the box and pull out). The motor is located on top of the
heater box behind the glove box door. There are two motor attachment
schemes used on Ford. The older models used screws mounting the motor
directly to the plenum box. With the screw attachment, you will see two
8mm head screws(note that a 5/16 socket will also work) in the front of
the motor. These are easy to remove. There is a third screw that is
directly behind the white connector socket that has to be removed with
a thin profile ratchet. Remove the three screws and pry up on the motor
to remove it. The second attachment method used on later models is a
plastic housing that is screwed to the heater box with a plastic pinch
attachment that the motor fits on to. The motor is removed by prying up
first on the front of the motor and when the front connector releases,
pry up on the back connector directly under and behind the white
electrical connector. The motor will just pop out.
The
picture of two blend doors shows the two most common fail modes. In one
the motor connector splits, leaving half of the axle connector. In the
other failure, the motor connector breaks completely off. The split
failure is shown from the top. Once you have removed the motor, you can
check by feel or with a mirror to see if the axle is completely broken
off or has half remaining. Either fail mode indicates a broken blend
door.
If
either of the fail modes is evident, this is a conclusive diagnosis
that the blend door needs to be replaced. An alternative that has
circulated on the internet is the “nail
fix�. This can only be attempted with the split axle fail
mode. We had our engineer do an analysis of this repair and the report
is posted on our heatertreater.net web site.
Another
reported fail symptom is a “clicking�
sound coming from behind the glove box. This occurs when the motor
gears get out of alignment and are slipping against each other, making
the noise. Sometimes you can make it stop by pushing down on the back
of the motor and getting the gears to catch. The failure usually
occurs with a broken blend door that allows the motor to get out of
alignment and twist slightly, causing the gears to disengage. The
HeaterTreater will put the system back in alignment and correct this
problem.
The HeaterTreater TM Solution:
This
kit replaces the plastic doors and axle with stainless steel
components. All work is done through the glove box opening and no
disassembly of the dash or evacuation of the AC system is
required. Tools required are a screw driver, pair of pliers, and
a Dremel tool( if you don't already have one, this is a good excuse and the tool has
many uses. The area under the dash is confined and you will need either
a stubby Dremel tool(~6� long), or a flexible extension
for a larger industrial rotary tool. Target has a new rotary cutter
product from Durabuilt for ~$30 that includes a flexible extension,
variable speed motor, and every grinding bit known to modern Chinese
technology(except the one you really need which is included in the
HeaterTreater kit ).
The repair will take about an hour the first time, and once you have
experience you can do another car in about 45min. No extensive
mechanical skills are required. The picture shows the metal
replacement kit. The plastic door is accessed by using the Dremel
tool and bit to cut into the plastic heater housing from the
bottom. Complete diagrams for the cutting pattern are
provided. It's a very simple process. The broken plastic
door is removed and replaced with the HeaterTreater TM .
The instructions are written with multiple pictures and dual level
instructions. You can read the bold print only for experienced
mechanics or read the bold and standard for full "instructions for
Dummies". The instructions are almost insultingly simplistic for
those who care to read the entire document without admitting that they
did it. The fix is really easy and MUCH preferable to disassembly
of the entire dash and engine cooling systems. We provide support via
email or phone if required. Our goal is to make sure that every
installation is successful. To date we have achieved that goal and have
no intention of letting up. This will solve the problems with the blend
door and is over-engineered to outlast the Ranger. All our
products are designed by degreed professional engineers and
manufactured to exacting specifications. If for any reason the
hardware ever fails it will be replaced at no cost.
100% Made in
Patent Pending
