rliles1

First of all, buy this 4 pin/7 pin trailer connector tester. It will let you test both the 4 pin connector and 7 pin connector to see if you have power to the connector. You have just eliminated 50% of the possible problems. If there is no power to those lines on this tester, the problem is in the tow vehicle. If there is power to the tester, the problem is in the trailer.

GCTruck

UPDATE: In case anyone is looking, the updated part number for the 7-pin wiring harness for a 2018 F150 is HL3Z-13A576-D . (This apparently replaces
FL3Z-13A576-B, HL3Z-13A576-B) I just ordered it from TascaParts.com for $20 (plus $11 for shipping). If this works, it will be a real time saver (no to mention keeping my new truck looking OEM).

stefantheterrible

I just did half of this install (harness and new socket) because I didnt want to wait the two more days for the actual controller to arrive. The install of the socket and harness went perfectly, but something weird happened when I went to test. Using a probe tester, hit the hazard lights and tested the terminals inside the 4-flat socket. They flashed on the tester the way they should. I then tested the prongs inside the 7-way, and got no current. I then tested the 4-flat terminals again and now I have nothing to them. This change happened in the course of a minute or so. I tested my probe on the battery, and the probe is good. Blinkers are flashing, just nothing to the socket.

Any ideas why the terminals would work for a few minutes and then stop? Does not having the controller hooked up factor into this? I wouldnt think I need the controller installed and activated to run the blinker terminals, especially since they were working for a few minutes. Has anyone tried testing the socket prior to installing/activating the actual controller?

GCTruck

I actually did the harness/socket install prior to the controller as well, but did not have your issue. I really doubt the controller would have any effect on the 4 prong leads anyway. Try a resistance test on the ground terminal first since that would explain the failure of both sides of the flashers. By the way, any difference if you do the turn signals separately instead of the flashers?

GCTruck

Update: It Worked!

montanaman

You guys are lucky - on my 2011 I had to run a 12v power wire to the back, because my truck with the 4 pin harness didn't have a power wire inside the front harness.

It is funny that the dealers don't know it can be done.

stefantheterrible

Update to my previously mentioned issue... after a few days, it miraculously worked like it ought to. I'm chalking it up to my own operator error when testing.

ricksf150

Just did this upgrade to the trailer wiring. One question . . . does the socket retainer clips hook to just the plastic or to the metal?

kvbit

Hi

just joined the forum as I just bought an F150 and did this install myself, was easy to do. Thanks for the write up much appreciated.

I wanted to add the oem trailer break controller and the dealership tried to install it today but said they couldn’t activate it. It got power as I have the 24 fuse in from factory but they could not get the software to work.
the plug is behind the coin slot and so it installed fine

Have anyone installed the oem ford TBC on an non tow from factory equipped truck?

Could it be a bad TBC or do I need a trailer break module installed as well. The dealership thought that might be the case.

My truck is a 2019 XLT V8 super crew

The part was JL3Z-19H332-AA
The parts guy thought I might need FL3Z-19H332-B and/or GL3Z-19H332-B

Appreciate any help, suggestions or thought

if anyone have successfully installed one on an non tow equipped truck I’d love to know

thanks

kvbit

Mind hooked just to the plastic. Seems to be In there solidly