Ford Superduty 4X4 Inop & Heater Stuck On Defrost Fix

[@chrisanderson9217]

Thank you! Looks like someone at the shop left the vacuum pump unplugged after some diagnostics on my truck and your video showed me exactly where to look so I didn't have to bring it back in!

[@VictorRamonethefirst]

I rode around for 5 days with this problem. Watched this video, looked under the hood and plugged that orange and yellow plug back in. Thank You so much on this 98 degree day.

[@melindavincil8825]

Love this video. It is straight- forward, well explained, and not drawn out like countless videos others made. All of uour explanations of the components and their functions helped me to diagnose and fix my ac problem. I knew very little about how to fix it or where to even start before watching the video. So I just wanted to say thank you for your time and help.

[@justincaton2344]

Had some work done on my engine. Next day noticed heater was stuck on defrost. Turns out they unplugged power to the pump, but did not quite plug it back in all the way. Thank you so much for this video. Saved me so much time and hassle! "F"

[@ToxicUFO]

I asked two questions in one of your other videos and as I've went threw your videos found my answers. Your videos are wonderful! Thank you so much, keep up the great work.

[@MuckoMan]

I think this is the same problem I have with my 2008 Grand Marquis. Once in awhile it would blow out of any of the vents but now it just blows out of the defrost. I'll check everything you said. I hope its the pump. I had a mechanic at work tell me I would have to take off my whole dashboard to replace a small switch box that was stuck. Your explanation makes more sense.

[@MTH1104]

This was absolutely the perfect video. Start with this and work your way around. I watched this and started with volt meter but mine was only putting out 5.6 volts instead of the 12v. Mine is a F350 4x4 7.3L Diesel '01 model. I changed the vacuum pump for $85 and look at that blowing air again through the vents. Thank you for the video.

[@colebroadbent4088]

Did you find out why yours only had 5.6 volts?

[@abe9829]

Thank you for the video. I watched all the videos and they were very helpful. After tracing all the lines I found the black line going through the firewall with the gray was clogged at the firewall grommet. Disconnect your lines and see if you can move air through. You can tape a string on and pull them into the cab to repair.

[@bigwave_dave8468]

Thanks for that great description and simple troubleshooting! -- I didn't recognize the pump as it's so tiny but when there's electricity, I can hear the motor running but no suck..perfect diagnosis.

[@josephsfields]

On your side you just get to hear how your video is awesome and thanks, thanks, thanks. I hope you know that what this really translates to is that your video provided a solution to a major problem that probably drug on for a long time or could have set some poor slob (me) back loads of money at the dealership. A huge thanks goes out to you every day I turn that AC/Heater control. New Subscriber.

[@conover1978]

Perfection.! Quick symbol little fix. Much appreciated thanks!!

[@blondstunter1]

Thank you for posting this video, you guys saved me time and anger! My problem was a varmint chewed the vacuum line from motor to tank!

[@maurovelazquezhernandez5654]

ok

[@mcnamee30]

Thanks! I have friend with a f250 and has the same problem.

[@oscarortiz776]

solved my problem thanks to this video

[@imjustthatfast]

I got a 06 6.0 250 4x4 my max ac works but if you switch it to regular ac it blows hot as if I turned heat on. The thermostat is still all the way on cold. And it will switch from defrost to floor etc. Any help would be greatly appreciated it also blows cold on idle but if your cruising normal gets hot and if you accelerate it cools back down I'm not sure where to start thanks in advance !

[@dpa0810]

I have a 2003 F250 5.4L 2V, Gas. My A/C would move to defrost under acceleration or heavy load (up hills). Issue was with the vacuum solenoid. There is no vacuum pump on a gas, no matter what the internet says! Part I used was Dorman 600-402 4WD Hub Locking Solenoid

[@cullendarling7916]

So this is why when I switch it to 4wd while I have the hvac on it switches to defrost.... right? Both 4wd and hvac work but I must be losing vacuum somewhere?

[@billmalec]

When mine does this, I go up and tap the pump and it starts working again. Been doing this for probably 12 years on my 7.3 Excursion. 😁

[@rickrick6933]

What I'd my vents are stuck on defrost but 4wd works

[@bruceestep7503]

Any reply

[@peterlaurancearmenio5545]

I’m having a strange problem I wonder if you can give me advice on I have an overhead heating air conditioning unit in my 04 Ford extra-large super duty E250 van i’m getting hot water circulating up to the unit but it doesn’t seem to be blowing any heat is there any type of relays that are involved switching between The AC unit and the heating coil unit I can’t seem to locate any schematics on this unit

[@dieselds678]

Do you have motorcraft part link for this vacuum pump FTM?

[@happy123854]

can you tell us where the transfer case shift module is located on a 1999 f350

[@user-dn6qy1ou1f]

It's on the driver side of transfer case. It's black

[@ChuckD351]

Any idea about blend door operating system

[@davidbrogan606]

Perfect, just what I needed. Thank you.

[@kevinrumsey3756]

I have had this problem on my ‘99 for a while now. Vacuum motor works, but still stuck on defrost. I have a friend that said try tying off the vacuum lines to your front air-locking hubs to rule out a leak at the hubs...tried that to no avail. Where do I check next?

[@user-dn6qy1ou1f]

Have to check each line

[@troykress1592]

So i have vacuum and i can take vacuum pump to the yellow red and blue and can get to move to floor and to vents.. but lost where to go next

[@DJ-sy8ht]

My problem is no defrost. Have air and heat in vents and floor. Where do i look for problem

[@robertcypress1699]

I’m getting a vacuum pump now, it had fire but wasn’t coming on. I took the cap off the back and saw the motor. Them twisted the shaft in the back to free it up and it came on. As long as nothing was connected to it, it would run but rough. Thank you a lot....

[@edmertins8072]

I have an 03 f150 gas. I only get hot air. I can direct it floor defrost panel. Why only hot?

[@jeffdunn7060]

is the 5.4 the same

[@tedyBear59]

What about the same problem on a 2009 F250?

[@terryloomis422]

A/C on my f-350 7.3 2000 is stuck on defrost afterr i had my clutch replaced. how ever i have a jack brake "6 speed tran" and when i activate works for a few minutes than back to my defrost.

[@michaelfontenot7259]

Does anyone know on a 2003 f350 the red vacuum coming off the ac control panel is broken but can fine where it go to behind glovebox one end goes to switch but other side broken but cant find where it plugs in at I looked online but no one seems to have a diagram or pictures PLEASE HELP

[@coffeeandsugar20]

Would this be why the vents stop blowing with AC on, but when I turn the AC off, the vent air blowing comes back?

[@ruizhernandeztrustfi]

Similar thing happened to me with my 2007 f-250 (xlt). But in my case the A/C temp stopped working after I changed completely the engine coolant. (the A/C system work but I can't adjust the A/C temp). My suspicion is vacuum trouble too. What do you think? Where to start to diagnose my problem? Help. Nelson

[@endurotruckererniedesjardins]

I know my seals on my 05 f250 diesel 6.0L 4x4 hubs are bad, my heater is stuck on defrost. Would vac leak at the hubs affect the dash functions

[@user-dn6qy1ou1f]

It absolutely will

[@timpermenter912]

My f250 7.3 fan is working intermittently. It will come on after driving down the road, sometimes. First sign of trouble was the blower air automatically shifting to the defrost vents when I would activate the 4x4 high switch. Vaccum pump motor??

[@FordTechMakuloco]

+Tim Permenter As long as your pump is working I would look at the 4x4 shift solenoid in that same area bolted to the fender they leak vacuum out the vent on top causing problems you stated.

[@timpermenter912]

+FordTechMakuloco I replaced the vacuum pump, 4x4 shift solenoid, fan motor and rubber vacuum lines on the hubs. The fan is now working everytime I turn it on, however with the AC on and blowing out of the dash vents when I shift to 4x4 switch to 4x4 high the fan shifts to the defrost mode.... Frustrating. The new pump is running and creats vacuum in the reservoir and shuts off, doesnt seem to be leaking down. Not sure where to turn now....??

[@sethdexter8317]

@@timpermenter912 I am currently experiencing the same issue in my 2001 f250 superduty 4x4. Did you find a solution?

[@timpermenter912]

@@sethdexter8317 Sorry for the late reply. I replaced the vaccum pump and it fixed the problem

[@franciscoramirez7035]

I have a 95 f150 when the ac is on goes to defrost and back to ac multiple times. can u help

[@bradypotter8209]

Ok I have no power to the pump. Where do I go from there? Fuses are all good checked them all.

[@johnosullivan6620]

I have the same problem did you figure it out? Did you replace the vacuum actuator?

[@tynelson5502]

And what if we have no power to the pump?

[@harleyd4280]

I am having this problem on my 2003 F150 HD, can you help me?? It's 101 degrees in Alabama, no A/C

[@acmethodman001]

Hello. So my pump runs but I still do don't have vacuum to that line. Is there something else I should look at?

[@user-dn6qy1ou1f]

Ya. Check all the lines. There isnt many

[@PKMCCOY-jb5gq]

I've been fighting this for way too long...Huge Thx as 2001 250SD7.3 4X4 w/ Only Defrost, No 4X4 @ 139K, is downright annoying and dangerous w/ this 2018/19 shitty Iowa Weather. this season. Interesting that None of the Local " Experts " here in Billyville, were even close. Experts are the Idiots away from home, drinkin my BuschLight and distractin the shit outta me, while insisting on throwing more parts at it, tearing dash to shreds and replacing both Warn Lockouts, blah blah blah. I will attack this as work schedule allows. I never imagined it May be as simple as The Pump. If Not, at least we check it off the list. Thank you, Sincerely, from The Heartland.04/14/19. AND the Fridge is still Fully Stocked !!! BONUS ! Of Course, You're Welcome Anytime, Ford Tech. Happy Wrenchin" and Be Safe Out there. Thanks again, Brother.

[@ryanswinemar1244]

Would this be the same issue in my 03 F 250 5.4, I don't have a vacuum pump and I have manual locking hubs. Thanks

[@endurotruckererniedesjardins]

Your vacuum comes from a fitting on the intake.

[@chanodelarosa3505]

I have a f250 my problem is the ac works but the only thing it doesn’t blow cold or hot air. Can anyone help or suggest how to fix the problem?? TIA

[@mrvass100]

No i was wrong, my pump was cooked.I have ordered another one.I remember hearing some thing that kept running when i turned on the ignition,never figured it was that pump running to its death.Now i expect to have a vacuum leak somewhere i suppose is that right?

[@FordTechMakuloco]

Yes vac leak for sure will make them never turn off.

[@mrvass100]

Thats all good, but my 4x4 still engages what could be the prolem there?

[@FordTechMakuloco]

So your 4x4 works ok but your heater is still stuck on defrost?

[@mrvass100]

So happy got my new vac pump.put it in and shut off after about 30 seconds or so no vac leaks:),Now everything is back to normal.thanks for your vid, people like me need people like you.

[@FordTechMakuloco]

Good to hear!

[@oritheo]

Thank you

[@dougstraining4999]

My pump runs constantly and still stuck in defrost????

[@keytr0n13]

Terrific video

[@Doubletap6996]

I thank you for this video

[@derickbartlow1250]

What if my plug has more than 12 volts going to it would that be a ground issue

[@user-dn6qy1ou1f]

It's going to have over 12 volts. The vehicle charges close to 14.4

[@paulkendrick5515]

I think that's my problem . Got to check. It

[@UrbanLegend911]

My 4x4 doesn't work and hvac is stuck on defrost thank you!

[@thomasmiller1943]

My 4wd doesn't work later on my ac got stuck on defrost

[@user-dn6qy1ou1f]

Vacuum lines or hub seals are junk

[@3fiftyone710]

🏆🏆🏆

[@RustyBaban]

thx you

[@landscapingfromthestart9946]

Why is my pump running all the time

[@user-dn6qy1ou1f]

It's not building pressure due to the big canister next to it leaking or the hose to it is leaking

[@stbennett7318]

Thanks too easy

[@1976corcho]

Ac stuck on defrost..my 4x4 works...what can i check

[@murkeyfuzwart]

Line had be chewed in half. Tanks

[@edwinlundstrom4649]

Way too wordy.

[@FordTechMakuloco]

ungrateful