Test OEM plug?

[gruss01]

Sorry if this is a newb question but, well I am a newb to towing. we have a 2003 x with the class III towing package, stock 7 pin connector etc. Well today while I was rewiring the 4 pin plug on the 98, I had the voltmeter out and figured I'd see what was up on the 03. It's never towed anything and we plan on possibly picking up a pop-up camper or something so I fired it up turned on the lights and hit a turn signal and couldn't read anything? Zeros across all pins? Pin-outs are right on the cover.
I'll admit I didnt even check the fuses because I got sidetracked but besides that anything else to look for? Do they leave that fuse out just for grins? Or do I need and actual tester or something? I don't have a problem tracking down electrical gremlins but I know nothing about towing and if Im missing something really stupid I'd rather feel the wrath here then spend 4 hours tracing it all out

Thanks

 

[gruss01]

Sorry for the bump, but a friend broke his foot and I may need to tow a motorycycle trailer next week and I have no power to that plug. All the fuses and relays seem to be in place and the fuses looked good but there is nothing coming out of the plug, got a four pin converter for it with test LED's and nothing. Anyone point me in the right direction???
Like I said this is the stock Ford Class III-IV towing package
Thanks

edit: Forgot to mention, I checked the ground on the plug too and no continuity back to the battery, thought maybe they tied the ground somewhere that corroded so ran a ground wire all the way back and tested for voltage with a known good ground path, still nothing so the whole thing is dead. the wires run to a plug under the left rear fender that is plugged in and snug. is there somewhere else that needs to be plugged together? I lost track of the wiring after that plug looks like it goes into the bodywork after that.

 

[gruss01]

Wow no one has had this problem of the stock plug not working?? There is power at the distribution box, I'm scratching my head on this one. Anyone know the route the wires take after they disappear into the rear fender? Maybe they make an appearance behind the glove box or something??

 

[gijoecam]

Check the following fuses in the battery junction box are present and working:

#27 (20A)
#13 (40A)

Also check the trailer tow relays are present in the same junction box... Don't know the locations off-hand, but they should be in the owner's manual.

There should be one for each of the two turn signals, and in the rear auxiliary junction box, there should be three relays: One for the parking lamps, reverse lamps, and battery charge relay. That AJB should be located in the right hand D-pillar. I can't seem to get the image to load at the moment...

But I suspect nobody ever installed the necessary relays.

 

[gruss01]

Thanks!!, relays are in place under the hood and the fuses are good and in place as well with power going to them. I'll have to figure out how to pull that panel off to look for the additional relays under the d-pilar, that sounds like alot of fun to get to

 

[gijoecam]

From the looks of it, it shouldn't be that difficult... From the diagrams, it appears you have to remove the top headliner panel trim (after removing the seal, of course), pop the C-pillar and D-pillar trim off, then the side panel should snap right off.... Allegedly. That's how it looks from the diagrams at least.

Good luck!

 

[gruss01]

thanks for the help, but it turned out to be unecessary!! I just started tracing things back again and it all looked to be put together so I popped the plug off the hitch just to see if maybe corrosion inside was the culprit and it came apart with little to no effort. I couldnt pull it apart from the back so it must have just been clipped or wedged in there but not installed correctly, little dielectric grease for safe measure plugged back together and its working!