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Trailer Wiring Harness Installation- 2005 Toyota Sienna

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How to Install a Wiring Harness for a Trailer on a 2005 Toyota Sienna

Today on this 2005 Toyota Sienna Van, we will be installing wiring harness part number 118304. The ports we are going to be plugging our wiring harness into are located directly behind the tail lights here at the rear of the vehicle. So the first thing we need to do is go ahead and remove both tail lights from the driver and passenger side. There are two inboard screws here that need to be removed and then we can pull the tail light right off. :24

With the two screws removed we can gently rock the tail light back and forth until the clips on the outside here release. With the tail light removed, plugged directly in the back of it is the port we are going to be plugging our harness into. So you need to separate the two, you can do that by pressing the tab here at the bottom side. We are going to go ahead and do that for both sides of the vehicle. :47

We are going to start over on the drivers side and make our connections there first. To get the wire over to the passenger side we are going to route the wire in the inside of the vehicle. To do that we will have to remove the interior panels along with the rear threshold piece. So we are going to go ahead and do that now. We are going to start by removing the rear threshold piece here. We have three tie down points that I am going to remove the mounting screws from. Take a flat head screw driver and lift up on the tab here and you can see the screws. Then we will come to the interior panel. I am using a rivet removal tool to release these clips here on the interior panel. Again we just need to pull it back enough to gain access so we can feed our wires from one side to the other. I am going to start over here on the driver side and go ahead and route our connectors. The driver side connector is the one with the yellow, white, and brown wires on it. We are going to take it and feed it from the inside of the vehicle out through the opening where we can connect to the tail light. We will simply plug our harness in line. And then we can go ahead and reconnect the drivers side tail light. Over here on the passenger side we will be connecting the connectors that have the red, white, and green wires. If we go back inside the vehicle here you have the 4-pole left, the converter box, and ground wire. The 4-pole we are actually going to store in the jack storage compartment. 3.15

We can go ahead and route it into there, but we also need to mount our ground screw in this area as well. I am going to go ahead and remove the jack to give us more working room. It will be easiest to ground the screw in this area down here. Next we want to adhere our converter box to a metal surface in the jack storage compartment area. Okay with the converter box adhered and the ground screw connected we need to start reassembling our vehicle. We want to make sure that when we put our jack back in its holder over here we do not pinch any of the wires. And again, when we reinstall the threshold piece we want to make sure we are not pinching any wires that are routed across here. With the interior reinstalled our installation is completed. If you have any loose wires here in the jack storage compartment you can tie them up out of the way using a cable tie that is provided with the installation kit. 4:21

A quick overview of how to use the harness. You simply want to take and pull it out the rear cargo door. You can close the cargo door on the wiring harness, you do not have to worry about it getting pinched because the weather stripping will prevent that. When you are finished with the harness you can store it in the jack storage compartment. And that will conclude the installation of wiring harness part number 118304 on a 2005 Toyota Sienna Van.

Info for this part was:

Employee Joe V
Test Fit:
Joe V
Employee Nicholas E
Test Fit:
Nicholas E
Employee Randy B
Test Fit:
Randy B
Employee Zack K
Video Edited:
Zack K
Employee Jacob T
Video Edited:
Jacob T
Employee Sue W
Video Edited:
Sue W
Employee Joshua S
Video by:
Joshua S
Employee Kathleen M
Video by:
Kathleen M
Employee Cole B
Installed by:
Cole B

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