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Shawn
Shawn, Auto Service Technician
Category: Ford
Satisfied Customers: 3756
Experience:  16 years experience Ford,Nissan and Honda dealership in all areas
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99 Ford F150, A/C - Heater Control

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'99 Ford F150, A/C - Heater Control

Shawn :

Hi, Thank you for asking your question on JustAnswer, my name is XXXXX XXXXX I will be assisting you today with your question.

Shawn :

What problems are you having?

Customer :

Looks like I lost what I'd originally typed in. Replaced a broken blend door & the actuator last week. Customer returned today with a popping noise. I found the door fully open in the heat position, with the actuator still trying to turn it further. Just the opposite in the cold position. Door not fully closed & the actuator already stopped.

Customer :

The door is still very smooth, no binding, etc. I do automotive A/C & Heating full time in my ma & pa small but very professional shop.

Customer :

Am suspecting the control potentiometer, but it is smooth & the actuator responds smoothly. Tried the second actuator & still same problem. Both the replacement blend door & both actuators are "Dorman" brand.

Shawn :

The clicking and poppind sound is most likely the actuator is the problem they will usually click or pop when the gears re worn, otherwise the blend door is sticking or binding causing the popping sound.

Customer :

The HVAC box was obviously removed & all was cleaned spotlessly.

Customer :

Yes, am familiar with that. It may be that the 1st replacement actuator bit the dust. I feel relatively certain that NO problem existed when I finished the vehicle a week ago. The customer left on a trip & before returning complained about the problem.

Shawn :








  • Insufficient, erratic, or no heat




  • Low engine coolant level.

  • Engine overheating.

  • Plugged or partially plugged heater core.

  • Temperature blend door binding/stuck.

  • A/C electronic blend door actuator.


Shawn :

If you need I can send test procedures.

Customer :

I tried another new actuator today. Didn't bolt it in, but with the tang engaged with the door, it turns freely as usual, but the blend door stops in the fully open (heat) position & the actuator is still trying to turn it. Just the opposite true in the cols position. Actuator stops & the door is not fully closed. No problems with heat, flushed & serviced the eng coolant system on the same visit.

Customer :

I am pretty certain that the just replaced blend door is fine. With a small piece of vacuum tubing inserted, I can turn the door freely with my fingers. Can feel it hit both stops with a nice little thud. Quite confident it is not binding. (8+ yrs self emp & 6 in large A/C shop prior)

Customer :

I feel the new actuator is probably OK. It is not OEM, but "Dorman" replacement parts have worked well for me in the past.

Customer :

I've replaced only a few control potentiometers in the past, but they are usually dead & or with dead spots & this one seems quite smooth.

Customer :

I removed the cover from the actuator & realized there is not "clocking" to it, the feedback potentiometer is a part of the output shaft, thus not adjustment or chance of mfg error that I can see.

Customer :

I guess I'd like to know if an experienced Ford Tech has ever had similar problems in the past. Again, unless the Dorman Door is somehow ill designed, I am quite sure that it is the correct door, installed properly with NO binding or anything obstructing it. I could simply try a replacement control potentiometer as it simply bolts to the A/C - Heater Control Head. I believe it is a YH1503, but I hate being a darn parts changer! lol

Customer: replied 6 years ago.
Relist: Other.
Shawn left the chat twice, apparently for good the last time. He apparently did not want to answer.
I've got to sign off until 8AM in the morning, but would like an answer if possible.
Appreciatively,
Terry

Hi Customer.

 

 

 

 

Thank you for asking your question on JustAnswer. The teating procedures are below, Please kep in mind Just Answer is set up on an honor system, If the answer has been helpful then Please don't forget to click on the ACCEPT button, so that I may get credit for my work, thanks.

 

 

 

 

 

 

 

NO OPERATION IN ALL THE TEMPERATURE SETTINGS
CONDITIONSDETAILS/RESULTS/ACTIONS
D1 CHECK THE A/C ELECTRONIC BLEND DOOR ACTUATOR MOTOR SYSTEM
Allow the engine to reach normal operating temperature.
Set the function selector switch to the MAX A/C position. Adjust the blend door potentiometer to full COOL (left) and check for cool air discharge.
Adjust the blend door potentiometer to full WARM (right) and check for warm air discharge.
Vary the blend door actuator control from full WARM to full COOL.

  • Did the air temperature change?
Yes The system is OK.
No GO to D2.
D2 CHECK FUSE 5 (15A)
Check Fuse 5 (15A)

  • Is the fuse OK?
Yes GO to D4.
No REPLACE Fuse 5 (15A). TEST the system for normal operation. If the fuse opens again, GO to D3 .
D3 CHECK CIRCUIT 295 (LB/PK) FOR A SHORT TO GROUND
Disconnect A/C Electronic Blend Door Actuator Motor C229
Disconnect Function Selector Switch C217
Disconnect Fuse Junction Panel C242
graphic
Measure the resistance between fuse junction panel C242-15, Circuit 295 (LB/PK), and ground.

  • Is the resistance greater than 10,000 ohms?
Yes REPLACE the fuse junction panel. TEST the system for normal operation.
No REPAIR Circuit 295 (LB/PK). TEST the system for normal operation.
D4 CHECK THE VOLTAGE TO THE A/C ELECTRONIC BLEND DOOR ACTUATOR MOTOR

Disconnect A/C Electronic Blend Door Actuator Motor C229
graphic
Measure the voltage between the A/C electronic blend door actuator motor C229-7, Circuit 295 (LB/PK), and ground.

  • Is the voltage greater than 10 volts?
Yes GO to D5.
No REPAIR Circuit 295 (LB/PK). TEST the system for normal operation.
D5 CHECK CIRCUITS 436 (R/LG), 437 (Y/LG) AND 438 (R/W)
Disconnect Blend Door Actuator Control C220
graphic
Measure the resistance between the following pins:
    Blend Door Actuator Control C220A/C Electronic Blend Door Actuator Motor C229Circuit
    Pin 3Pin 4436 (R/LG)
    Pin 2Pin 3437 (Y/LG)
    Pin 1Pin 6438 (R/W)

  • Are the resistances less than 5 ohms?
Yes GO to D6.
No REPAIR the circuit(s) in question. TEST the system for normal operation.
D6 CHECK THE A/C CONTROL POTENTIOMETER
graphic
Measure the resistance between the blend door actuator control terminal 2 Circuit 437 (Y/LG) and terminal 3 Circuit 436 (R/LG).

  • Is the blend door actuator control at full WARM greater than 3,000 ohms and at full COOL less than 300 ohms? Is there a linear variation in the resistance between COOL and WARM?
Yes GO to D7.
No REPLACE the blend door actuator control. TEST the system for normal operation.
D7 CHECK CIRCUIT 57 (BK)

graphic
Measure the resistance between the A/C electronic blend door actuator motor C229-8, Circuit 57 (BK), and ground.

  • Is the resistance less than 5 ohms?
Yes REPLACE the A/C electronic blend door actuator motor. TEST the system for normal operation.
No REPAIR Circuit 57 (BK). TEST the system for normal operation.

 

 

 


Thank you again for trusting us with your problem. Please reply as soon as possible so that we can finish answering your question.

Shawn and other Ford Specialists are ready to help you
Customer: replied 6 years ago.
Thank You Shawn!
The info you provided gave me what I needed to troubleshoot & confirm the A/C & Heater Control Switch (potentiometer) was out of specs for resistance. I had tested it during my initial diagnosis, but only to confirm that it was smooth & that the resistance was indeed changing. I also had a Broken BLEND DOOR & the original Blend Door ACTUATOR was bad, completely dead. The replacement worked, but with a bad A/C & Heater Control, the actuator was not closing the blend door in the full cold position & was trying to over close in the full heat position.

Have the new one on order from our local Ford Dealership. Thank you again.
Have a Blessed & Merry Christmas !
Terry R