Hello there. I am in need of help to try and figure out what is going on with my truck. It is a 2001 Ford f150 four door supercrew v8 triton. Some of the many issues are: The ABS light keeps coming on and the 4x4 light flashes on and off at random times while driving. The windshield wipers sometimes wont work then wait about 30 secs and then they work along with rolling down the power windows. If wipers are not working neither will the windows. mostly happens when its raining. of course just the times i need wipers to work... right? Then the other issue is that if i have the defrost, heater on in a on position and i shut off the truck the blower unit continues to run, even with the keys out of ignition until i turn it to the off position. Also while having the heater running in any of the fan setting whether high or low it seems to really bog down the engine and it make a weird sound. Any advice would be very much appreciated. Thank you.

 

I may have answered a question like this in an earlier post.
There have been some difficult problems to explain when the windshield leaked on the GEM module under the left side of the dash. Things started working on their own and other functions sometimes worked and sometimes did not. Water from the leaking windshield got into the electronics and , well symptoms like you are seeing appeared.
There were times the problems went away after the leak was repaired and other times the GEM had to be replaced. To attempt to do a repair without correcting the windshield leak was an exercise in futility because it just took a while and the replacement module suffered the same effects.
A thorough examination under the dash in that area for rust and possible corrosion is a tip off the problem could be there.

 

Thank you Hanky for your feedback. To the best of my knowledge the windshield is not leaking. However i do not know the condition of the windshield prior to my owning the truck now. I already have almost all the dashboard taken off. I seem to be having an issue on the passenger side finding all the screws to get off, all in a effort to try to test the blower unit at the wire connector. So while i'm in there ill for sure check for moister and rust. Thank you again for the feedback i appreciate it.

 

I agree with Hanky on this one. The leak may not be evident, but after working on these things for many years, that is the most common concern. Sometimes it is the windshield, but I have also found a body seam leak on the driver side and do the same thing. You must use a electronic leak detector to find the leak, but if you remove the GEM module (located on the back of the fuse box) you may find signs of water entry and possibly corrosion.

 

On top of whatever is happening to my heater and abs light, windows and windshield wipers, another issue more serious has happened that i need help with. Lately every time i try to start my truck is wont start. It cranks over like it wants to start but no go. Everyone is saying i have to drop the fuel tank to get to the fuel pump because they all think its the fuel pump. Thats a lot of work and im not that skilled of a mechanic. Im really wet behind the ears so to speak. If it wernt for this forum and youtube id be lost. anyhow. When i turn the key i can hear the hum of the fuel pump. so im thinking it works right? also if i spray starting fluid into the air intake then i can usually get it to start. So if it were a bad fuel pump would the truck continue to run after spraying starter fluid into it? I did a test light to the place that the relay goes in the fuse box. i get a green light on three of the four posts that are in the fuse box. i dont know how to test the actual relay itself. and thats the fuel pump relay i am talking about. Please any help would be appreciated cause getting stuck for hours on end at a store or at my sons school is no fun. thanks

 

Not ignoring the former problem,,,which could be contributing to the present problem, let's see what we might suggest.
If you can hear the fuel pump run for the usual 2 seconds when first turning on the key and not turning the key to the start position would kinda confirm that everything is working up to that point. AND, if it will run with a shot of starting fluid would , almost, confirm a fuel supply problem. When cranking the engine over does the check engine light go out, it should!! If not, that would indicate the loss of the RPM signal which the computer(PCM) requires to keep the fuel pump relay closed and the pump running. The best way to confirm this is to connect a fuel pressure gauge to the tap on the fuel rail on the engine. You can rent a fuel pressure gauge from most auto supply stores to do this check. The pressure should be over 45 psi, if not fuel pump has a problem which could be electrical or mechanical.If the pump has never been replaced it would seem a candidate for replacement. If you are not familiar with working with gasoline , it is a job best left for an experienced shop.

In rereading your last post, if it continues to run after getting it started with starting fluid, all that means is power is low to the fuel pump circuits and the charging system is helping to overcome the low voltage supply ,that may be caused by the electrical problem at the left underside of the dash , it could all be related there.