Toyota FJ Cruiser Forum banner
1 - 14 of 14 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter · #1 · (Edited)
I bought this 07 yesterday and was giving it a look over today and noticed this under the hood? I am thinking it may have went to a security system or something. The white and black wires go through the dash and to maybe the radio. And think gray wire goes down the firewall and I can’t tell where it goes toward the back of the vehicle. Any ideas on what this might be? Thanks you your help and input.
Johnny
 

Attachments

·
Registered
Joined
·
3,140 Posts
It's hard to assess this as the pics do not show the power source or point of termination. These appear to be large gauge wires (8-10 gauge ?). Could it be the previous owner had a trailer with electric brakes? Can this same wire (gauge and color) be found going into a seven pin connector at the tow hitch? I'm only guessing here.
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #4 · (Edited)
Thanks for the quick reply. I added some more pictures, the power source is the battery itself. They run straight to the battery. Could this be a wiring hack to have the rear dif lock and a trac to work at the same time? Because this 07 was built in June of 2006.
 

·
Registered
Joined
·
216 Posts
That looks like an etrailer brake controller upgrade. there’s two videos that show how to install it on the etrailer web site. I did that upgrade earlier this year. First you have to add the Toyota towing package upgrade. Then the 7 pin (for brakes) etrailer upgrade package. I recognize the gray cable and resettable circuit breakers.


 

·
Registered
Joined
·
152 Posts
I am beyond anal about wiring ... so free-form routing of wires that are not protected inside proper wire loom and are not properly fused drives me crazy. And then there's the non sealed crimp connectors. They also did not use cross-link (high-temp) insulated wire ... something I always use ... especially in engine compartments. For me, I would not care what the wiring is for ... and would completely remove. Nothing worse than a "Carbeque" caused by hack wiring.
 

·
Moderator
Joined
·
30,590 Posts
Welcome and Congrats!

You should have a brake controller box under the dash somewhere? If you don't and don't want one, then I'd remove all of this.

Standard "Camping World" hack job of running power to the Trailer brake controller. Ask me how I know... :rolleyes:
Motor vehicle Automotive tire Gas Tints and shades Auto part


From the battery, the Black and White are usually power to the box and the gray runs to the trailer for power. Another wire taps into the brake light switch behind the pedal.

Remove that rear 7 pin splice job. The Toyota OEM trailer flat 4 harness plugs into the back of this Hopkins 7 round adapter that gives you both Flat 4 and 7 Round (I had 2 trailers). Then run completely new from front to rear for the other 3 wires.

Any non OEM trailer wiring should be removed = the OEM kit has to be used with its 2 fuses, 1 circuit breaker, and control box. The square harness connector is at the left rear frame rail below the jack compartment.
Automotive tire Motor vehicle Hood Automotive exterior Rim



Amazon.com: Hopkins 47185 Multi-Tow 4 Flat to 7 Blade and 4 Flat Adapter : Automotive

Automotive lighting Font Auto part Cable Gas


Automotive design Gadget Camera Font Gas


Amazon.com: Oem Toyota Fj Cruiser Hitch and Harness Kit : Automotive
 

·
Registered
Joined
·
6 Posts
Discussion Starter · #12 ·
Thanks for your responses, I agree it’s probably a brake booster controller. I think the blue painters tape was just used to mark the wire and not as a splice. I will look at that closely to make sure it’s not a splice.
I thought it looked like a pretty good install, I don’t do a lot of towing so I may remove it all. Happy thanksgiving everyone.
 

·
Registered
Joined
·
152 Posts
... little boxes are actually automatic circuit breakers that trip when the current exceeds its rating (typically 20 or 30 amps), and then they automatically reset. Those posts should be insulated with proper caps.
 
1 - 14 of 14 Posts
Top