Hi,
I too have no idea where to put the relay, is it necessary?. I bought the wiring kit (4-plug) from the dealership for 100 bucks

, and the instructions are horrible

, they do show where to put the 15 amp fuses but they do not show where the relay goes

I tried it in one of the open slots but my trailer lights still don't work.
I also used a circuit tester and found that there is no power coming from the 4-plug of the FJ?
And I also wonder what that computer chip looking thing with the mount bracket is? Is that for brake control?
Thanks for any help,
Jephellis