I bought a 2004 FX4 F-150 about 3 months ago and it won't start.

It was running fine until a week ago when the battery died. Got a new NAPA battery with 850CCA. It has drained after a 40 mile trip. The batt light came on and the truck died. Tried to jump start it from another truck and it wouldn't at first then I moved the shift lever from park to neutral and back to park and it started.

Drove it home a couple of miles and no intsruments/no brake llights - nothing. I tried to charge the battery with a charger and it wouldn't charge. I currently have the batt charger on it with the hot lead disconnected from the truck and it is charging fine.

Do I have a dead short??? Help!!!!!

 

From advice I found on another web site, I checked the wiring bundle under the driver's side door.

It was full of dirt, gravel, dry mud, etc.. Cleaned it out, blew it out with compressed air, cleaned the contacts and put it back together. Then I reconneced my new battery and now everything seems to be working just fine.

No warning lights on the instrument panel. Truck started and runs fine!!!! yeah!!

If you have a 2004 or newer model Ford F-150 truck, you probably need to check this connector. It was seriously corroded inside!!

Peace out !!!

 

After a while I noticed the battery light came on again!! Turned out to be a bad alternator. Anyhow, I bought a 200 amp replacement and will put it in the truck Tuesday if hurricane Harvey has passed by then!!!

Anyone else had this problem with the wiring connector corrosion under the driver's side door???

 

Thanks for sharing the information!

 

That seems to be a common issue.

 

I wonder if geography & environment have anything to do with it. Here in sunny California, I don't live in a snow region, and there is no road salt.

 

I don't really think that is it. The underside of the truck is really clean especially for a 2004 FX4! The previous owner of this truck probably kept it in a garage. The entire truck is so clean it still has the plastic on the carpet from when it was new. You know the ones that say to be removed by dealer.

Anyhow the connector for the wiring is under a plastic cover which is just held onto the truck by two plastic push clips. Under that cover there was some mud and some gravel. In the connector it was filled with dirt and the pins were black with corrorsion.

This was causing a dead short which killed my battery and what looks like a new alternator.

During the process of getting my transmission rebuilt the mechanic pointed out that I have a new engine block - 5.4 liter!!

Now I practically have a new truck.

 

No. The problem is due to water getting into and staying where it isn't supposed to be.

 

No Prob. If I can help someone else with this, it has been worth it!!

 

Good to hear you got it figured out! Good luck with the truck, I love mine hope to have it around for several more years.

 

Thanks, me too! A few days ago I got my new "Made in U.S.A." alternator which is an upgrade to 200 amperes. I installed it and everything works great now!! Even tested it by driving in the rain (what was left of hurricane Irma) a couple of times. Now that I know everything is good, I will apply some really good insulating tape that is waterproof around that connector. Don't want to have to replace the battery and alternator again!!