Non functional OBD port 2004 Expedition

[MikeS]

As the title says, not getting a reading with scanner. Only fix I see online so far is it's a blown fuse. Well it isn't, all fuses OK. Any suggestions?? I see that the cigar lighter and the OBD port are the same fuse. The cigar lighter is also not working

Any Help will be greatly appreciated.

 

[Trainmaster]

You are lucky if the cigar lighter is on the same fuse and it's not working. Trace the circuit and see where the failure (ground or hot) is. In the worse case, energize it from another source through the cigar lighter. If this is beyond your ability find a shop that knows auto electric and pass along that information to them. Some of these fuse boxes develop problems and windshield leaks have caused corrosion in these 18-year-old trucks. You can probably trace the pins and find the problem that way if you want to go through the trouble. Often just finding the proper connectors through the wiring diagrams and wiggling the plugs will find the problem.

 

[MikeS]

Thanks "Trainmaster". I have never been smart enough to figure out electric issues. I have an idea what you're saying to do but yep, it is "beyond my ability".

 

[Vincent Vega]

@MikeS yes, the cigar lighter and OBD port are on the same fuse. If you have not already, I suggest replacing that fuse regardless of whether it looks burned out, because A) sometimes it is hard to determine visually, and B) a blown fuse is the most likely cause of your issue, and C) fuses are cheap. Same thing happened to me, thanks to my kids stuffing chewed gum into the cigar lighter, which toasted the fuse. I found out when I went to get my Exp smogged. The dude could not complete the smog check because OBD didn't work. So I removed the fuse for the horn and stuck into the spot for the cigar lighter/OBD (they have the same amperage rating) so he could get it done, then bought a new fuse on the way home.
Follow the link below to download the shop manual and wiring diagrams, if you need them (if replacing the fuse doesn't fix it). Good luck.

https://cardiagn.com/2003-2006-ford-expedition-navigator-workshop-manual-wiring-diagrams/

 

[GONS]

Had the exact issue last week on my 2004 Navigator. OBD port dead. It had been working earlier in the week. In my case, blown fuse. As Vincent Vega suggested, replace the fuse even if it passes a physical inspection and a resistance test. And of course audit to make sure you have the proper OBD fuse identified.

 

[MikeS]

And again, no reading on the OBD port, almost exactly 1 year after I first posted about this issue.

I will say, when this issue first arose, I wound up disconnecting the battery cable and it reset the check engine light until now.

Is there any reason the light comes on other than a pollution control issue?