2003 f250 fan controls not working
 

Hey guys, just recently noticed noticed that my fan only blows on defrost and will not switch to vents for floor of dash vents no matter if I switch to a.c., defrost, floor or dash vents. The actual switch just take a crap or what? Any ideas would be awesome cause its been pretty hot the last few days. Thanks

it is probably a vaccum leak or the vaccum pump itself is bad, it is located on pass side fenderwell right behind the battery. Turn the key on and with the hood up just unplug one of the vaccum lines from the pump and it should turn on, if not check the fuses and the pump itself.

I'm trying to trace down a vacuum leak myself...

At the top of the page you'll see a sticky for diagnosing 4x4 auto hubs not working, it's the same issues, just read that, there's a video posted in there that explains how to trace it down.

any chance someone can post a pic. of the vaccum pump. Im pretty sure I have found it, a electric connector on top with two vaccum lines connecting to the middle part of the body of the pump?... Do the vaccum lines just pull off the body of the pump or is there some sort of snap connection?

They pull off, but the fittings are barbed, so sometimes it's a little difficult. Standing on the passenger side, looking into the engine bay, you should see the vacuum reservoir (big black plastic housing just to the left of the battery), the pump is just to the left of that towards the fender.

If you watch the video in the thread I'm talking about, he shows you exactly where all this stuff is... :pca1:

I'm having the same problem with my ac. In the video he says it will blow on defrost when you put it in 4wheel drive. Mine stays on defrost all the time would it still be the same problem?

Yes, that's what mine is doing, it's still a vacuum leak somewhere. I'm tracing mine down right now. I just replaced the lines going from the vacuum pump down to the hubs, no change, tested the reservoir itself, it's holding vacuum. Have it narrowed down to either the solenoid right by the vacuum reservoir, or the hub seals.

I checked my line and I don't have any vacuum at all. I pulled the lines off of the resevior and got just a little puff. Then with engine running turned 4x4 switch on and got nothing from the lines. I should have felt some suction right? :humm:

if you pull a line and key is on the pump will run, and its a noisy little thing so you should be able to hear it allright

So I either a bad fuse or a bad pump.
Fuses are cheap. Anyone have an idea how much pump is?
Thanks for the info bob.