bing tracking image
Q & A Icon

Why Does Trailer Wiring Harness have to Connect to battery on a 2011 to 2016 Toyota Sienna  

Question:

I just saw where one of your experts said you shouldnt use the trunk 12 V outlet to wire the wiring harness. He said it would put the whole electrical system at risk if there was a short in the trailer. However if you include the 10 amp fuse and if it is a dedicated line only servicing the 12 volt outlet then I cant see how it would be a problem. If there were short in the trailer it would blow that that fuse. So how could it possibly damage the car system if you include your 10 amp fuse. The only problem I can see with doing it is if you use the 12 V adapter in addition to using the trailer wiring as you might blow the car fuse. But I have another question when not using the trailer when the car is turned off does the converter use any electricity?

0

Expert Reply:

Powered trailer wiring harnesses are not tested or rated for any alternate installation method. Installing it by attaching the power wire to a power outlet 12 volt wire will void the warranty. Also many times those outlets are not the only component on the fuse and/or there could be a relay that has other functions. So if the wiring harness is drawing power and whatever else is fused with it or that uses the same relay is drawing power then it can cause more costly electrical problems.

You probably know already that routing the power wire to the vehicle battery isn't difficult; it just takes time. I have included a link to a help article I wrote that offers some tips for routing the power wire for you.

On powered harnesses, because they attach directly to the vehicle battery they have power all the time but unless something is plugged into the connector and drawing power it doesn't run down the battery.

If I was choosing a wiring harness for a 2011 to 2016 Toyota Sienna I would go with # 118498 because we hear about less problems with the Tow Ready brand. I have included a link to a video showing an example installation for you.

expert reply by:
0
Michael H

Products Referenced in This Question


Product Page this Question was Asked From


Q & A Icon

Continue Researching

See More Q&A Expert Answers >>