Frontier 12 volt wiring problem

Roamey

I see there are a few Frontier drivers out there, hope someone can help. I have a 2012, 2wd, V6, 6 spd manual. On the trailer plug there is no 12 volt power. Everything else works (lights). If I go to the brown relay behind the passenger kick panel and use a jumper wire for the 12 volts, then I have the 12 volts at the trailer plug. Anyone know why the relay isn't activating?  I haven't been able to find any bad fuses and I don't have a repair manual. 

ScottG

I have a 2015 Frontier V6 with factory tow. There are lots of fuses, fusible links, and relays behind the passenger kick panel, but no brown relay clearly associated with the 12V trailer plug line. Can you post a picture of what you are looking at?

Relays can go bad, but the last one I remember replacing was a starter relay on a 1980.

Not much help, I know, but I am curious as to what the problem is and how to fix it.

Roamey

This is a towing harness that had to be purchased and plugged in to an empty socket in the factory harness that included two relays for automatic and three relays for the manual transmission. Perhaps it is an issue of when it comes on rather than why it isn't activating. 

ScottG

My bad. I was looking in the engine compartment behind the firewall, not (as you clearly stated) behind the kick panel. I'm not familiar with what is behind there on my 2015--since mine came with factory tow, I didn't have to purchase or install any additional wiring, and I've never had a need to open that area up.

So, I'm still not much help. I'll poke around some more if I get the chance, as post back if any bright ideas surface. Please let me know if you figure something out in the meantime. 

Roamey

I finally found a fuse. I know, I said I checked them, but not the right one. I can find no printed list of fuse function and location. I guess you are supposed to pull off each fuse cover and look at list under the cover. Then you can't look at fuse and see if it's blown. Have to use test light. I downloaded some repair manual pages; they are clear as mud. 


This shows trailer relay 2 going through fuse 38. 


This shows a trailer tow relay going through the light switch. I didn't want that, so I concentrated on the one above that shows fuse 38 with 12 volts, which is what I'm missing. 


This shows me where fuse 38 is and tells me it is fuse F16. 


Finally, here is F16, the red one at the end of the test probe. You might make out on the cover it says TTow reverse lamp. See?  Clear as mud. 
The fuse panel behind the glovebox door has a fuse puller and spare fuse. 

ScottG

That looks familiar--same configuration as my 2015 (also a M/T, but 4WD). Did you actually find a blown fuse? Did replacing it fix the problem?

In addition to F16, I also notice F4 (another 10A) is labelled "TRAILER TOW." There's also a 30A fusible link further forward in the same box labelled "TRAILER TOW." Further complicating matters, there are several trailer-related relays and whatnot in the box just in front of the one in your photo.

Not that I'm sure what any of these mean, but it does raise the question of which plug pin you are lacking power at. On mine, the center pin is the one that feeds power to the reverse lights, if your trailer is so equipped. The 12V feed that charges the battery comes through the pin at ~1:00. That's a different circuit all together, but may be related to those "Trailer Tow" fuses.

Just guessin'--I agree it's clear as mud. Do you have a link to where you found those wiring diagrams? Now I'd really like to know how it all fits together.   

Roamey

The fuse was blown and after replacing it, I had 12 volts at the 1 o'clock pin. Don't know if it will simply blow again. Here is the link I bookmarked for the 2012 Frontier. http://www.nicoclub.com/FSM/Frontier/2012 Frontier/. 

ScottG

That's odd, since the reverse lamp should be the middle pin, but again, I 'm just guessing based on what seems logical. Like you said, clear as mud...

Either way, I'm glad you got it resolved (and hope it stays that way), and I got to learn a few things about my own truck. Thanks for the link to the diagrams.

atlasb

Some one I talked to about this said to run a 10 Gauge wire with a 30A inline fuse back to the TV connector and connect it to the 12 wire going into the connector.  The connector indicates which pin is what.  Haven't tried that yet.  Had a cover installed with a 12 port in the back and that is basically how they got power for it. 

dsatwork

atlasb said:

Some one I talked to about this said to run a 10 Gauge wire with a 30A inline fuse back to the TV connector and connect it to the 12 wire going into the connector.  The connector indicates which pin is what.  Haven't tried that yet.  Had a cover installed with a 12 port in the back and that is basically how they got power for it. 

I did my own wiring for both the 7pin connector and the brake controller. Just as you say I ran the 10 gauge wire from the battery to the 7pin connector. I used a 30 or 40amp 12v Automotive Auto Reset Circuit Breaker