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Trailer Wiring Harness Installation - 2008 Nissan Altima

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How to Install a Trailer Wiring Harness on a 2008 Nissan Altima

Today on this 2008 Nissan Altima we are going to install part number 118470 from Tow Ready. The first thing we need to do on this install is get inside the trunk area and remove the carpeting. We are going to remove this plastic also. Start by taking out the rivets, they pop right out. Use a screwdriver to get the rivets started and then take a trim panel tool. Pull out the middle. Work our way across. All right we have got the threshold gone, lets remove the carpeting. We are going to repeat the same process back over on the passenger side. We just took apart the driver side. 00:39

Our T harness is split into two halves. The red and green wire is going to go over to the passenger side and the brown and yellow wire is going to go over to the driver side. Look for the wiring connection. This connection will be the first connection that comes out of the tail light. It should be this connection right here. This little button you have to push and it will come apart. We will take this in and plug it back into place. You will notice we have got a ground wire here so we are going to attach that to the sheet metal of the vehicle itself. So you will peel this wire back some and we will use the sheet metal right here. 01:11

Lets find a spot to mount our modulite. There is a nice flat spot of sheet metal right here and we will just adhere it to that. Now we will take our other wires and we will follow along the factory harness to the passenger side. Take our excess and zip tie it to itself and we will be finished with this side already. Now we can put our interior back together on the passenger side. We are done on this side. We will go back over to the driver side and we will start work on routing our power wire up to the battery. The next thing we want to deal with is the red wire coming off of the modulite and this red wire is going to be ran up to the battery. We are going to use the butt connector that came with it and crimp it on. Then take the black wire and strip it back. Put that to the butt connector too. Make sure the connection is good and tight. Then we will take the rest of our wire and run it through the grommet that is a little bit farther up in the trunk pan. What we are going to do next is take our black wire and tuck it underneath the carpeting and we will pull out our 4-pole. We are just going to leave that with the spare tire right now. Then we will zip tie everything together. Tuck the wires safely out of the way and we will just leave it at that. 02:32

We ran our wire through the grommet, we appeared above the suspension components, stayed above that, and worked our way around the gas tank, crossed over through the fuel lines, and went over to one of the main frame channels going all the way down to the front of the vehicle, and push it up into the engine compartment. We pulled our wire up from the bottom up to the top. We had to pull it through a couple of times to make sure we did not get around anything that was hot or moving. Basically we want to stay as close to the firewall as possible and we are going to tie off to the wiring harness that is next to the brake fluid reservoir. We are going to run this wire, we are going to snake it around this electric box and then we will come up to our positive terminal and make our wire connection right at this nut. We will get our fuse holder ready. You can see it comes as a loop. Cut it in half. We will have the ring terminal to the one side and the butt connector to the other side. It does not matter which end. We are going to cut our black wire short. We will install our butt connector to these two wires. On the other side we will install our ring terminal. The next thing we are going to do is disconnect our negative terminal and then we can disconnect the positive. We changed the ring terminal to a smaller size than when it came the kit. This nut really did not want to budge so we are just going to use the clamp bolt here to tie off from it. We are going to use the clamp bolt to make our attachment to. Now reconnect the ground and then we are going to install the fuse. Just tuck that back down safe out of the way. Next thing you need to do is turn the key to the on position for the car and then we will check out our wiring for the light tester. To use it just pull it out and just stay away from the center latch and just put it down to your trailer hitch and you can shut the trunk on it. So when you are not using it store it inside and it is not getting corroded by the elements outside. There you have it for part number 118470 from Tow Ready.

Info for this part was:

Employee Joe V
Test Fit:
Joe V
Employee Brent H
Test Fit:
Brent H
Employee Robert C
Test Fit:
Robert C
Employee David F
Test Fit:
David F
Employee Zack K
Video Edited:
Zack K
Employee Joshua S
Video Edited:
Joshua S
Employee Jacob T
Video Edited:
Jacob T
Employee Dustin K
Video Edited:
Dustin K
Employee Sue W
Video Edited:
Sue W
Employee Chris R
Video Edited:
Chris R
Employee Andrew K
Video by:
Andrew K
Employee Jonathan Y
Video by:
Jonathan Y
Employee Cole B
Installed by:
Cole B

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