Hi - Have a 2006 King Ranch...I've exhausted my efforts via reading existing threads.

Bottom Line Up Front: Truck will occasionally not start. The systems power up, but when I go to crank...nothing (to include no sounds). I replaced the starter relay and it fixed the problem. However, it happened again...I replaced the starter relay again just in case I received a faulty unit. Temp fixed the problem, but happened again. Now I've learned if I pull the starter relay out, and plug it back in...truck will start. I've been able to reproduce this "fix" a few times. Thoughts on what's going on?

Additional Background: I've been plagued with an electrical issue for years. They/it include parasitic draw killing batteries (I now use a trickle charge to cheat the problem), few instances of truck dying while driving (lose everything...lights, power brakes, power steering...insanely dangerous), and thrown charging system errors (forget exact code). Truck has a fresh battery & motorcraft alternator. I, and a shop, have pulled every fuse and couldn't locate draw.

I'm decently handy/mechanical but am a novice with diagnosing electrical issues. Tempted to get a new truck but not with current prices...help me buy some time! Your insights are appreciated!

C_

 

where the relay fits, are the holders for the pins all tight so there is a good set to conduct? Have you looked into the guts of the fuse box for possible corrosion?
apologies if you have.

 

Mods - Apologies if this is the wrong section. If this belongs in the 2004-2008 area, please feel free to move...

 

Thanks for the reply! It fits snug. I haven't examined the internals of the fuse box. I'll have to do some research on how to go about that, but will add it to the list.

 

snug could mean 3 of the 4 pins are tight. you actually should look to see if all are tight.

 

Makes sense... Any suggestions on what to use for the "drag test" for the slots? Wish I kept the old relay, could have broken one off... Couldn't tell if the guy in vid was just using a regular needle or some kind of purpose built tool to test the pins...

 

does leaving starter relay unplugged/removed stop the draw/drain?

have you tried disconnecting alternator to see if it is causing draw/drain?

is there, or was there ever aftermarket accessories (remote start, alarm or aux lights)?

 

Bought another $5 relay and harvested a pin so I could test one-by-one. All pins snug, except for the center pin...which slides in/out without resistance. What's the fix?

 

I'm not ignoring you. I got tired of disconnecting the battery to test so I ordered a clamp multimeter that is capable of reading DC mA.

I also went a little crazy with throwing parts (sick of this) and will be replacing some of the key contributors to wonky electrical problems (ignition switch, FPDM (it DOES look heavily corroded), and BSM (body security module). Regarding the BCM, after pulling the back seat out (boy that was fun)...I'm fairly certain it's gotten wet. There is rust behind the seat, and I've had issues with water leaking in that area in the past. Will be hosing my truck down while girlfriend monitors behind the seat soon as well. Don't want to replace the part just to have it get wet again...

 

Yup, rear sliding window leaking from corner closest to BSM module...pretty bad too. The irritating part is that I had a dealer do work on it while under warranty because it made the most annoying creak when hitting bumps. Whatever they did didn't fix the problem, but now I wonder if they caused a new one...