Towing harness issue SOLVED!

Dude this is such a niche issue and you guys are killing it - i believe my towing converter relay is also shot. All of the lights work on the truck - none are working on my trailer. I checked the 30amp fuse in the front for continuity and its good and i checked the tow relay in the engine compartment fuse box and read 70 oms across the coil and open to the third leg so i believe thats good. I am getting no power at all to the connector and when i check for continuity between the ground pin out of the connector and the frame of the truck its no connection. Would the failing trailer converter relay also show a dead ground on the 7 pin connector on the truck? If not - then where is the harness grounded? I looked under the truck and about midway along the harness somewhere around where the tank is is see the harness held in place with a white clip to a rusted bracket. That bracket is the only rusty thing in that area ... could it be grounded there or does it use the ground in the engine compartment for the trailer harness as well? I took apart the trailer harness up to the first connector and read good continuity in the harness up to that first connection. Any help would be appreciated!!

 

No. Trailer Socket Ground is NOT controlled by the towing converter.
But it does go through plug BE1.

Also, Ground is pin #6
7 is Brakes

 

So does the mean that is likely that the tow converter relay is good and its just a grounding issue on the truck itself? Again - all the lights work - no power to the outlet. Not even reading ground on the outlet .... i did check every pin to the frame in case i mixed up the ground and they all read open...

 

With the Key - ON.
You should have at least power to pin #2. (Marked battery +)
And ground at all times to pin #6. (Marked Ground)

Check this, and we will continue from there.
If you have no power or ground at the connector, we need to work our way up the harness and find the "break".

 

2014 doesn't have a Towing Converter if it's the factory tow package.

The trailer plug grounds at Ground Point BD on top of the frame behind the left rear wheel.

 

ok - my truck is a 2014 trd off road package and the tow package is oem. So assuming that there is no towing converter i will check for the ground!! that picutre shows perfectly where it should be - i will also check the pins wit the truck idling and see what i get. Thansk!!

 

I was/am a bit confused.
He says....No power to outlet.....??????
And no Ground?????

That's why I went with the harness first.
BE1.......

 

Converter is part of Towing Turn Signal Flasher....

 

So i checked for ground and nothing - i turned the key on and all the lights and there is no power coming from the pins (since there is no ground even if there is power i don't think i would have detected a voltage drop across the pins anyways) i took the relay out and the coil reads around 60 ohms - i also shook it and couldn't hear any sounds, is it a solid state relay or should i hear the contactor shaking around in there when i do shake it? just to confirm 81980-04050 is the part number im looking for? I looked at the ground to the frame and it looks solid, no rust around it. I also took apart the harness up to the first connector and checked from continuity to the ground pin on the receptacle and it tested 0 ohms. the harness itself looks brand new almost - no bruising no tears/rips no marks on the convoluted tubing. Thanks!

 

How are you checking for power back there? I'd reccomend using a test light connected to a known good Ground to check each pin.

 

Ok - so i removed the ground and cleaned it and connected the trailer again . now the brake lights work and only the passenger side blinker - it has to be the towing relay converter correct? If so, where is it located? I've been looking everywhere for instructions on how to get to it!

 

Look for this next to cab fuse box:

 

Do i have to remove the kickpanel on the front? It seems like its deeper than just the fuse box - i understand this seems like a very simple thing to do, i just really dont want to break anything,

Also - based on only some of the trailer lights working but all of the truck lights working - it has to be this correct? What else could it be?

 

Pretty sure you have to remove the knee bolster.

Could still be a broken/corroded wire/bad connection.

Need to see if you have output on Pin 18 (Brown) of the flasher with the Right turn signal on.