Ok my expedition 5.4 eb started to blow the 30 fuse under the dash out every time i turn the key.

This started like 8 months ago so the truck just sat till i had time to look more into it today, So i was searching on the net on this forum and have found out radio interference suppression capacitors will cause this problem. So i unplug both of them and put a new fuse in and the truck started right up without blowing that fuse,

So i let it sit running for 30mins cause it havint ran in 8 months, So i went to move it by puting it in drive and asoon as i put it in drive i herd the fuse pop and the truck shut right off...

So i figure i try another fuse in it and every time i turn the key its blowing it out like its been doing.. even with the capacitors unplug..


So pretty much im really stumped cause i thought that fixed it sense it ran perfect for 30mins in park, But asoon as i went in drive it popped and stalled out..
does anyone know what else will cause this to do this? I mean unplugging them capacitors got it running. But died when in drive. and now the problem is back.
Really need this problem fixed.

Thanks


I wanted to give a update of something. Now that i look at pics i saw what i pulled that i thought was the capacitors could be the in ignition coils... Does anyone got a good pic or something that shows were the capacitors are at? Cause what i went by is this pic from this thread https://www.ford-trucks.com/forums/1...e-blowing.html which is hard to see were everything is at. Kinda feel stupid.. lol but i hardy work on vehicles just trying to help my parents i did get it running for a bit tho lol Theres just alot of plugs in these expedition...

 

Are you referring to fuse number 30? Or a 30amp fuse (of which there are three of them under the dash)?

 

number 30 fuse.

 

in 1997 the fuses under the dash only go up to 29.

 

Not on mine. mine goes up to 31 under the dash. Even in the book it came with when i had it showed it go up to 31. But that book got stolen.. Also mine is a eddie bauer 5.4 not sure if that would make a difference?

 

Check the PCM diode feeding the PCM's relay.

If that passes the diode test, try unplugging all the COPs and turn the key on to see if the fuse holds. If it does, plug each COP in to see if one of them causes the fuse to blow.

 

Maybe yours was built late in the year because I just check a 1998 and it has the 31 fuse spaces like yours.

 

Have a update, I finally found the radio interference suppression capacitors, They was by the firewall on each side of the back of the engine, which everywhere else i saw was in front of the engine..

So i unplugged those and i also unplugged the fuel pump and also the pcm fuse under the hood just in case, And i turn the key and it didn't blow, So i put the pcm fuse back in and try it again and it didint blow.

So than i hooked the fuel pump up and went to start it and it started right up and ran strong, I even took it around the block and it still ran great so it was those causing the fuse to blow.. i was wondering do i have to replace them? Or can i just leave them unhook? I would just do with out them but im not sure if it would hurt anything?


Also i have couple more problems, I just found out the turn singles not working and sometimes when you turn the windshield wipers on they wont shut off half of the time... This stuff was working when it was last parked 8 months ago.. and i checked the fuses and they good, Now it does have a bad battery which i always have to have a jumper on it to start it, Will that cause any problems with stuff going crazy? Im not sure if i should start a new thread for this problem or should i just use this thread?

 

A bad battery can cause all kinds of electrical issues. I'd start with a new battery to see if the issues clear up.

 

yea im going to go get one tomorrow sense this one has a 3 year warranty, Will give a update than Really hope that will solve these 2 problems.. cause everything worked when it was parked 8months ago..

 

Don't rule out the possibility of critters having gotten in and chewed up a few wires.

 

Do you have a moonroof?

 

Nope i don't have a moonroof on it.

But i did fixed the turn signals it was a fuse that i didn't know that deals with them which was fuse number 23. It was blown. So the turn signals are working perfect now.

But i still have the annoying wiper issue..

The rear wiper will not shut off so i had to pull the fuse under the hood to get it to stop..

And the front wipers will not shut off unless you turn the truck off and than back on and they wont turn on till i turn them back on which to turn them on i have to move the switch all the way up and they ony run on one speed and wont shut off..

Also if you put it on the wiper washer that will also not shut off and will keep pumping..

I don't think its the muti switch because we replaced that back than.

Is there any other else will cause this?

 

Everything is solved and working now

My uncle came and looked at it and we forgot that he put a new fuse box in it about 9 months ago because we thought it was bad and thought it was blowing the 30 fuse out, So we tried the old fuse box in and everything works perfect now even the wipers..

So the new fuse box which came out of a 2000 or 2001 was causing all the problems...

But glad its all up and running now Really weird why a fuse box will cause the wipers to go wacky..