Ford Super Duty (1999-2016) :: Heater / Defrost Circuit Does Not Heat Up

My 2006 F-250 SD with 6.0 diesel has some sort of cut-out for the heater circuit, and possibly for the A/C as well. This truck was probably a fleet vehicle for the Houston Port Authority. Didn't really notice this peculiarity until it got really cold outside. If I start the truck up and let it idle for 10-15 minutes the water and transmission temperature get up to the normal operating ranges but the heater/defrost circuit does not heat up. Cannot defrost the windshield.

If I drive to the end of my driveway, about 600 feet, the heater/defroster starts putting out good heat. When driving, if I have to stop at a stoplight, or any other pause, with the truck still in gear, the heater output starts to cool down. I suspect that this feature was incorporated in the circuitry at the factory to prevent the driver from sitting still to keep warm. The truck MUST BE MOVING to allow heat or defrost to operate. The blower motor operates and it doesn't matter if the truck is in gear or not.

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Ford Super Duty (1999-2016) :: 2006 F250 - Heater Will Blow Cold Air Unless Driving At Highway Speed

I have a 2006 f250 and the heater will blow cold air unless you are driving in like highway conditions. If you stop or drive slow it blows cold air only. What is causing this???

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Ford Super Duty (1999-2016) :: F250 - AC Blowing Through Defrost

1999 F250 7.3 4x4 switch on dash with manual hubs. No visual vacuum hoses cracked.

Not sure what this component is but when I wiggle the wire at the orange cap a small motor kicks on.

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Ford Super Duty (1999-2016) :: F250 - A/C Goes From Defrost When Accelerating?

I have a 1999 F 250. When I accelerate my AC from the vents changes to the defrost. Other than that it works great and is ice cold. Why it's doing this.

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Ford Super Duty (1999-2016) :: F250 - Skipping / Surging Under Load

I have a 99 f250 that seems like it has a bad coil, under a load it starts surging or bumping ( like it has in the past and I found a bad coil), I went through and unplugged each coil one by one while idling, couldn't find a bad one, so I bought a new coil and went through and rotated the coils, nothing worked, no check engine lights on.

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Ford Super Duty (1999-2016) :: 2006 F250 - AC Changes From Vent To Defrost On It Own

2006 F250 5.4 - While driving ac changes from vent to defrost on it own..let off gas and it will change back to vent. I replaced vacuum can under hood.. no luck.....

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Ford Super Duty (1999-2016) :: 2006 F250 - A/C Has A Blend Of Defrost

I know there is a motor or switch that I can remember the name of that is in the dash somewhere that controls the Defrost and regular cabin flow. I am not good with A/C, and was wondering, what is the name of it, and is it something I can get to behind the glove box or is it very complicated?

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Ford Super Duty (1999-2016) :: 2005 F250 - A/C Blowing Out Of Defrost

The A/C on my 05 F250 6.0 recently would not blow out through the vents. So, I replaced the vacuum pump and the reservoir tank. Once I replaced them the A/C still starts through the defrost vents but, after a minute or so starts to blow through the vents. I also noticed that the vacuum pump never stops running. Is this normal or is there something else I need to look for?

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Ford Super Duty (1999-2016) :: 2001 F250 - Defrost Stuck / Won't Come Off

My defrost is stuck no matter which way I turn the control it won't come off. It just started doing this today. I think it might be a vacuum leak. When I turn my switch on the pump still clicking whether or not it's pumping.

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Ford Super Duty (1999-2016) :: 2005 F250 Blowing AC Through Defrost Only All The Time

My 2005 F-250 6.0 liter Diesel FX4 Lariat is blowing AC through defrost only all the time. I have manual locking hubs and when I engage 4x4 it works perfectly through the ESOF switch. So I am assuming the vacuum pump and lines to the hubs are in good working order but there is possibly a cracked line or fuse blown? I've only had the truck for 2 days and it just happened after purchase. I'm a little unfamiliar with checking vacuum but have done reading and I believe I can do it. I am going to get a manual hand pump and pump to 20lbs and loss shouldn't exceed 1lb per minute. I just need to know which direction to look. Everyone else had their 4x4 not working and I seem to be the only one posting that has ESOF 4x4 capability when the defrost only issue is on.

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Ford Super Duty (1999-2016) :: 2005 F250 - A/C Switches To Defrost When 4X4 Is Engaged

My 2005 F250 just had the cab off in December for head studs and gaskets. Its a Crew Cab short bed FX4 so it has ESOF. When I engage 4x4 the blower will switch from blowing air out of the vents to blowing air out of the windshield defrost. Is a vacuum line plugged in wrong somewhere, or is one cracked? Trying to figure this out, its rather annoying

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Ford Super Duty (1999-2016) :: AC Switching To Defrost While Driving For Approximately 15 - 20 Seconds

I have a question about a possible leak. As I never really paid attention to it until of recent days, I noticed that my a/c is switching to defrost while driving for approximately 15-20 seconds then I let off the petal. Would it be time to search for a leak or could it be a solenoid issue. Also why we are on the subject would this have a negative effect on my mpg. I'm usually around 9.5 hwy and 8 around town, 6.5-7 towing 10k trailer. 06 350 cc lb v10 4.10's Factory 275/65/20's 69k miles...

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Ford Super Duty (1999-2016) :: 2005 F250 6.0 - Climate Control In Defrost Mode All The Time?

My 2005 Ford F250 6.0 diesel CLIMATE CONTROL DEFAULTS TO DEFROST mode all the time now. For some reason I'll turn on the AC and it is either already in defrost or changes to it no matter what I do. Is the head unit in the dash the problem or is it a vacuum leak or an electrical issue?

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Ford Super Duty (1999-2016) :: 2006 F250 - While Shifting Into 4x4 A/C Heat Blows From Defrost Vents?

2006 F250 with the dash controlled 4x4. I typically keep the front hubs locked on this truck. I have recently noticed that when shifting into 4x4 that the a/c or heat will switch from blowing out of the vents to blowing out of the defrosters. Any clues how to fix this?

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Ford Super Duty (1999-2016) :: F250 Pings Bad Under Load - Hesitation / Surging And Crappy Fuel Economy

2 wks ago I was running down I95 at about 95-100 mph (basically floored) in a rush to get somewhere on time. Since then my truck has been running for crap. It threw the p0171 code when I checked it. When driving under normal conditions it pings a lot and my mpg is down about 3 mpg and has this hesitation when you get on it. Even when you accelerate at a normal rate it surges a little, it pings a lot and has a loss of power, about 30-40%. It feels really sluggish and doesnt want to pull and then you will feel it starting to pull a little harder then it starts to surge/hesitate a little again.

Truck has 147k on it. I was having a similar situation until I had the plugs replaced at 125k, so I figured the plugs shouldn't be the problem. So I replaced the fuel and air filters, cleaned the maf w/maf cleaner and Throttle body w/tb cleaner and replaced the pcv with a new one from ford. Still pings bad under load and still has the hesitation/surging and crappy fuel economy. Its running smoother but no fix yet. This is crazy trying to pinpoint this issue. The detonating isnt crappy gas because I used super and it still detonates quite a bit.

Its a 06' F250 5.4 3V XLT Lariat SC FX4....

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Ford Super Duty (1999-2016) :: 2006 F250 - Climate Control / AC Vents To Defrost And Blow Normal Air Through

I have a 2006 F-250 Super Cab with climate control. The last three years when the temp exceeds about 85 degrees outside it acts up. It will switch from the AC vents to defrost and blow normal air through, not ac cold. Then it will switch back, when doing so I can hear the internal deflector shudder. It will do this every few minutes. It is extremely annoying. All other times of the year it works fine. My local dealer had the truck last year, but could not find anything wrong. I have used the search and also Googled and while I find similar problems nothing exactly the same.

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Ford Super Duty (1999-2016) :: 2006 F250 - Retaining Steering Wheel Controls With Dual Head Unit

Bought a new touchscreen head unit to put in my 06 lariat f250. I have all the controls on my steering wheel for heat and radio and I don't want to lose them with a new radio. This head unit does not have the 3.5mm jack for the axxes unit but has 3 wires labeled swc1 swc2 and swc ground. It supposedly has the converter built in. any views on using a headunit with these wires?

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Ford Super Duty (1999-2016) :: F250 V10 - Smell Coolant When Heater Is On

I got my 1999 f250 super duty v10 about a month ago. It had 200,700 some miles on it. It's now at 201,865. My issue is when I turn on my heater I smell coolant. It's kinda strong. No leaks that I can see. Not in the ground or in the cab or from what I can see of the heater core. It only smells when the heat is on, no smell on the cold setting. It sat for months before I bought it from a dealership. What it could be? Ok now it sounds like I have the ticking death sound. The one people have said happens when spark plugs are about to fail. So I guess new plugs are in order.

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Ford Super Duty (1999-2016) :: 2001 F250 - Heater Not Blowing Hot

2001 F250 5.4. The heater will blow warm air at idle and on the second highest setting, once you start moving or turn the fan up to full blast it instantly cools off. The coolant level is fine. The engine runs at a normal temp.The blend door does work. I just replaced the thermostat, and both hoses for the heater core are hot.

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