Best option for tapping into rear battery
- Thread starter mikerorke
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OP
OP
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- #2
Quick update here. Went ahead and connected to the open terminal (yellow arrow above). According to the red terminal cover, this is a fused (200A) output. I added my own 40A breaker just to be extra safe. Compressor works great and much easier to access power through the upper door with the jack behind it.
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Thanks for posting this and for the clear pictures! Do you have a link to the parts?
A winch install Youtuber said that there was a current sensor on the battery positive. I presume in the fuse box. So wiring a high current device to the fuse block instead of the battery is probably correct. Toyota likely wants to engage the hybrid to 12V charge controller when high current load is sensed on that little battery.
I plan to do the same takeoff as Mike for my compressor and probably a rear receiver winch. Although with a bigger breaker if I use one.
I plan to do the same takeoff as Mike for my compressor and probably a rear receiver winch. Although with a bigger breaker if I use one.
OP
OP
I hate to be wildly optimistic, but they may have considered that some crazy owner would modify the vehicle. Yes, even without written approval of senior Toyota engineering management.
But I do note that they did not include a nut. Probably as a silent head shake of disapproval.
@mikerorke , what type of port did you wire? It's not really visible from that angle in the final photo.
OP
OP
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- #8
4GA cable connecting battery positive to 40A breaker: Amazon.com
Do you have a link to the parts?
40A breaker: Amazon.com
6GA 'pigtail' with anderson plug: Amazon.com
OP
OP
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- #9
Its a standard 50A anderson plug - they are usually grey but also come in red. It also has a black dust cover on the end which makes it look odd. I cut the battery clips off my compressor power cable and wired them to an anderson too for easy hookup without having to remove the plastic tray to get to the battery panel
OP
OP
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- #12
Nice looking install!
I use those C/B a lot and would like to offer you a small piece of advice. Those little rubber caps tend to fall off, leaving the terminal exposed. I actually cut them off now. I use these from Amazon, hard to slip over the stud but will not accidently slip off either.
OP
OP
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- #13
Great advice - I will do that. Thanks!
I don't think Dissent was comfortable about how to connect the winch. But you are right that even a smaller winch would pull more than 200 amps under high load.
the dissent winch wiring
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What size nut goes on the terminal that you used? Nothing I have around the house seems to fit.
I believe you need a metric size...
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- #17
I think the L/H stud (unused) is an 8mm and the right one is a 10mm, I don't remember.
I’ve mentioned this in other posts just to be sure that nobody has the same F-up that I had. I believe any winch will draw more than 350a at some point and that fuse link assembly (what holds those 200a and 350a fuses) is only available from Toyota if you buy the entire hybrid cable system. I believe it’s $2000-3000, I don’t remember specifically but point being it’s VERY expensive considering what you actually need for replacement. If either of those fuses blow, it will completely disable the truck, no power to anything, so i would recommend attaching to the battery positive terminal itself instead of below those fuses (or upstream) of those fuses. The way original poster is fine with an appropriate breaker, but having gone through the worst case of this already, I just try to put it out there everytime I see it. The blue arrow is where I attached my winch cable, and all breakers are up front.
Also, where OP tapped in, that terminal is unoccupied (at least it is on my 1958, maybe it’s occupied on another trim level, I don’t know), but the 350a spot (where the grey terminal in the picture (in yellow) is, is what connects to the battery under the hood, and I highlighted the “housing that holds these fuses (in orange) that entire thing is what you’d need to replace and can only be purchased with the whole cable system that connects the hood battery to the 12v battery there… including the labor to take the whole truck apart… it’s an incredibly expensive oopsy. Have appropriate breakers!!!
