Clarification of Installation Instructions for Trailer Wiring Harness # 118553 for a 2012 Nissan NV

Question:

The yellow fuse holder has the ring connector attached to the + side of the battery and the other side connected to the black wire going back to the T connector module power wire if I am right. What is the little other square thing with the short wire. In picture F it looks like it is connected to the - side of the battery. Very confusing since the instructions do not say what the thing is or where to put it. Please clarify. Also my second question in step #8 it talks about locating the red 12 ga. wire on the T connector box. Is this on the module what you call t box connector? Because in step 7 you reference it as module.

asked by: Steven M

Expert Reply:

The square box that has all of the wires coming out of it is the converter box. The converter box is needed because the vehicle works on what is called a 3 wire system and trailer work on a 2 wire system. The converter box converts the 3 wire signal to a 2 wire signal so the trailer lights will work properly.

The short wire on it attaches to one end of the black wire included with the harness. That is routed under the vehicle and into the engine compartment near the battery where it will attach to one end of the yellow fuse holder wire. The other end attaches to the positive battery terminal just like you have said.

In the instructions, linked for reference, picture F just shows the fuse holder wire being cut in preparation for making future connections. Picture E is just a diagram explaining that the converter needs to be attach to the positive battery terminal. Picture G is just showing that one end of the fuse holder wire receives a ring terminal and the other is butt connected. It is not attached to anything at that point.

Step 8 is calling the module or converter box the T-connector box. There is only one loose wire to connect to so I am not sure why they decided to use that terminology.

expert reply by: Michael H