4th brake light blew tail light fuse? wat?
 

Hey guys,

Just recently installed a Valenti 4th brake light to compliment my existing Valenti tail lights and have encountered an issue. Upon plugging in the 4th brake light harness, it appears to blow this fuse upon startup:
https://i.imgur.com/TUEgoW7.jpg

It also may be helpful to note that all I had done was plug in the 4th brake light harness. I didn't do any of the necessary wire splicing yet to hook it up to my tail lights, so I'm not sure what to do. Blowing this fuse shut off my fog lights, side marker lights, running lights, and license plate lights, so I can't just plug it in again. I was told by someone it might be a circuit issue and that I could use a relay, but I want to see if this has happened to anybody else here and what I can do to go about fixing it.

Thanks!

I believe they recommend unplugging the battery when doing this install. Did you?

Quite possibly a defective light assembly...

I did not. I was following various video tutorials and I dont recall ever seeing anything about disconnecting the battery. I will try this tomorrow and get back to you on that. Thanks!

I didn't disconnect my battery. verify that the wire colors on the new taillight connector match up with the wire colors on your cars connector. I don't know if this has changed in 2017 model.
It's possible it's a faulty light. I would get a 12 volt power supply and test the light's functions and verify everything functions as it should.

I have a my 2016 BRZ and I took no precautions on installing my 4th brake light. Nothing broke and everything worked as advertised. I already had the valenti sequential brake lights installed, but that was the only mod I had done at the time of installation. I suspect something is screwy with the wiring of your car, perhaps how the foglights were wired from the dealer if you have foglights. My dealer wired them strangely and I only found out after installing new foglights. The valenti 4th brake light definitely makes use of the foglight circuit