Anyone have any experience with the climate control in these trucks? I assume it's the same with the newer F-150s as well.

I had it set to single zone 68 degrees and it was about 75 out. My side was blowing room temperature air and the passenger side was blowing cold air. I then put it on lo manual AC to remove the temperature control and got cold air on both sides (the same temperature.) I then put it back on 68 and it went back to how it was before.

A few hours later I tried again and this time my side was very cold and the passenger side was actually hot. It makes no sense. I'm thinking this is a warranty issue. The truck also pulls to the right, so I need to get that looked at.

 

I understand the system a little bit. There are actually other variables that have input on the temperature blend motors and fan speed, but the most important functionality is thus:

The grille right above the push button engine start is the sensor for in-cabin air temperature. When you set a temp, the system compares the value you set with the actual cabin air temp. Although the system temp control is not very precise, 75 to 68 is a fair differential to where you should see A/C (although remember, its not outside air that the system is checking). On single zone, there should be no temp differential in what is coming out of the vents. (However, it might take a second for temps to equalize, and due to evaporator location typically biased to passenger side, the A/C might be slighter colder on that side because there is less plumbing to heat the air).

For dual zone operation, there is no secondary cabin temp sensor on the passenger side. Instead, the system calculates how much the temperature blend door needs to move in order to achieve the temp difference you want. Obviously, fan speed must remain constant to both sides (some expensive cars like Range Rover actually use a left and right side blower).

Outside ambient air temp is checked to determine if A/C needs to be used or not for cool settings, and you can see what the system has decided based upon whether the A/C indicator light is lit on the HVAC controls.

As for pulling to the right, check your tire pressures (maybe with an actual gauge to verify the on-screen readings are correct). My dually tires were actually inflated significantly higher on the driver side rear and it also pulled slightly right until this was corrected. Dealer PDI is supposed to check all these things before delivering to customer, but most dealers are lazy and do not. You'll be lucky if they wipe the dust off the dashboard.

 

My truck came with about 10% more air on the passenger side than the driver side. I had a gauge from my old truck but it broke when I tried checking the air so I need to get another one

As for the climate stuff, thanks for telling me where the sensor is. Based on your experience, with dual zone OFF shouldn't it blow the same temperature air out both sides?

I am also glad to hear you say the AC is biased to the passenger side as I figured this out just feeling which side gets colder the fastest.

If the temperature sensor for the cabin is in/near a grille (I assume by grille above the push button start you mean the vent itself) then it can't really calculate once the system is on. In that case there's no real feedback?

 

No, not in the vent. See vent circled in red.

 

Thank you for the clarification. To me the word "grille" means a shiny vent, not an un-shiny vent. So this was just my misunderstanding.

It would seem if the vent to its right was adjusted a certain way it could affect the ability to read.

There's no sensor for the passenger side? So if dual-zone is off, it should produce the same temperature air on both sides, right?

 

If the vent is adjusted downward or in that general direction, it will indeed have an impact. It kind of is a dumb location...but common among many manufacturers because it is cheaper to run a short wire over to the HVAC ECU. Mercedes used to put their sensors in the roof with the front map lights, right above the rearview mirror. Because the air was blowing forward, it did not affect the reading much and because its hotter up near the top of the car, the A/C reacted much better in my opinion. With most auto climate systems, users get frustrated and pretty much use it like a manual system: full cold or full hot; when desired temp is reached, they dial it back.

There is definitely no passenger side sensor. Just the computer formula to calculate the temp door. So yes, on single zone, temp should be very close to the same, especially after 10 minutes or so. Like I mentioned, the side with shorter ducting to the vents might be a little hotter with heat or colder with A/C...but those temps should normalize once the plastic ducting basically heats or cools.

 

Ok, so last question. Given my original post's description of what occurred during the three times I tested it, would you say that mine is working normally or has a problem?

I've had one knowledgeable person tell me it's probably a bad motor in a blend door, but I'm not sure that makes sense because the situation reversed itself on attempt #3.

 

I think you may have a problem with a blend motor / door sticking. With the engine off and full accessory power on, run the fan on lowest speed and switch the temp dial from full heat down to full cold and carefully listen. You should be able to hear the servo motor moving. See if you can hear it stopping prematurely. With the climate set on dual zone, you can check each side individually and see if there is any difference in the sound. Also check your other blend door "outlet" functions. Make sure it switches properly from defrost to vent to floor.

The good news is that the dealer should be able to read blend door codes and "see" the problem. The bad news is that replacing a blend door involves removing the entire dash.

 

I wish Ford would listen to this about the blend doors. It is not a common failure but it happens more than one would think. It was the demise of our Lincoln LS. The thought of a 10 hour (book) disassembly of the entire dash told us it was time to go. No A/C and heat had to be set to fail safe 85 in order to get heat.

I would think the trucks have that same fail safe for anyone who might experience a failure in the system, but I hope no one ever has to use it.

 

Another shame is building the heater core and blower motor into the dash instead of in the right hand corner under the hood. Those days, when the motor went, it was a 20-minute job and you were back in business.

 

And I used to buy the cheap Mexican heater motors 2 at a time. Once you got the squirrel cage off the first time and used anti seize on the shaft it was easy. Then I found that Motorcraft motors (They were $30 instead of $9) would last the rest of the life of the truck. Foolish savings on my part.

 

You need to look at more XL trucks with the un-shiny black grille up front.

 

Sorry for the delay in getting back to you, Troverman. I am kind of down on the truck right now since I can't get it fixed properly so I've been occupying myself with other things.

I took it to a dealer today and they looked at the HVAC. The system had 5 or 6 HVAC communication codes. They cleared the codes and updated the software in the system. It seemed to work but after about 30 minutes of driving it went back to being warm (but not hot) on one side and cold on the other. It was 58 outside and the temp was set to 64 single zone.

They want me to come back at the end of the month. It sucks that something as basic as HVAC cannot be made to work as we go into the colder season.

I hear all the doors moving, BTW. They said they ran a test and the blend doors all actuate correctly.

On another note, I can't fix my bedside panel until a little piece of plastic comes off back-order and that'll be at least another month.

 

This has been fixed I think. The truck has never made it from the dealer to home (about half an hour) without exhibiting the problem. It behaved exactly as I would expect. I will take it on a longer drive this weekend.

The problem was there are sensors in each vent, and they coalesce into a connector for both the passenger side sensors and driver side sensors. The connectors are the same, but the looms are different colors. The connectors were plugged in backwards, so the computer was controlling the temperature on the wrong side. This explains all my problems and I expect it to be fixed.

Luckily they only had to remove the top panel by the sony speaker on the dash and didn't have to pull the dash apart to find the issue.

Sucks that they left it idling for a while to test it My distance to empty dropped like 25 miles. (The fuel doesn't bother me but leaving the truck idling is something I want to avoid.)

 

That was good trouble shooting to figure that out. Glad it was easy. I wouldn't worry about the idling but if you are, just hook up a trailer and get the exhaust good and hot. EGRs get plugged only after thousands of hours of soot accumulation.