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I have a 1999 toyota tacoma and it has a 4 pin harness for…

i have a 1999 toyota...
i have a 1999 toyota tacoma and it has a 4 pin harness for towing trailer but i need to change it to a 7 pin connector to be able to operate the trailer's electric brakes and to charge the battery. how??
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Customer reply replied 4 months ago
can you help me??
Answered in 6 minutes by:
3/13/2018
Skyvisions
Skyvisions, ASE Certified Technician
Category: Toyota
Satisfied Customers: 14,994
Experience: Toyota Master Diagnostic
Verified

First giving you specifics and walking through this step-by-step is probably a bit much to make this kind of conversion. However you need to buy the seven pin socket the basic wires for taillights ground wire running lights and turn signals will all be taken from the four wires from your four pin plug. You will need to get a brake controller and that will have instructions on how to wire from a good solid positive battery source through the controller and that that main wire will go back and be one of the other three pins that you will need. Typically most people then take a second wire to supply the battery charging pin of the seven pin connector from the same main battery source or junction block. Typically everyone goes straight to the battery you will have to run at least 10 gauge wire from the positive battery post make sure it's fused at about a 40 amp or 50 amp fuse. Or you could use in an 8 gage wire from the positive battery post into the left kick panel then splice off with 2-10gauge wires one for the brake controller and one back for the positive battery charge wire that you need for the seven pin controller you just need to route those wires through the cab down along the frame next to the main harness that goes to the bed.

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Customer reply replied 4 months ago
stand by please

I'll be online for a while this evening. If you need any additional specific information feel free to reply and I will get back to you. Otherwise if you've not done so please do not forget to rate the assistance I provided to you today at three or higher and a five would be awesome thank you.

Skyvisions
Skyvisions, ASE Certified Technician
Category: Toyota
Satisfied Customers: 14,994
Experience: Toyota Master Diagnostic
Verified
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Customer reply replied 4 months ago
yeh but hold on a minute please
Customer reply replied 4 months ago
the trailer has a 7 pin connector on a cord.
I think I need to mount a 7 pin receptacle on my tacoma correct?

That is correct. You will need to buy the socket receptacle and bracket it usually comes with about two or 3 feet a wire. In the kit it will also have the directions on which wire needs to receive which input for example taillight wires typically brown, yellow and green are typically turn signals and so on. Make sure you take the right wire from the four pin socket it's on there now you won't need a converter box it will already be configured for that for the four pin connector on your truck. You will just need to run the two additional heavy-gauge wires to supply the power to the brakes which would come from the controller and the controller that you purchase it any parts store will give you instructions on how to wire that. Then you just need an additional 10gauge wire back to run the battery charge for the battery in the trailer. Those pins will also be identified in the seven pin socket kit that you buy. It's not overly complicated just follow step-by-step and wire it according to the pin identifiers in the seven pin socket that you purchase. Just make sure all your wires are zip tied firmly to the factory harnesses it comes back to the cabin under the bed. Make sure you fuse those supply wires to the controller and the battery supply lines so that if they short out it will pop the fuse near the battery and not melt anything.

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Customer reply replied 4 months ago
gotcha so i have to buy two separate 10 ga inline fuses too correct.
any recommendation on a kit manufacturer?
should it be tacoma specific?

Yes that is correct it will take about 50 foot roll usually you look at about 15 or 18 feet from the front of the car to the back of the car. That's the safest way to do it. 10 gauge wire will handle 30 A without any problems you should not need much more than that through the brake controller and definitely not for the battery charger you might even be only get away with a 12gauge wire for that. I probably wouldn't go much thinner than 12gauge to charge the battery in the back.

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It does not have to be Tacoma specific just go to your local parts store they can hook you up with a decent controller doesn't have to be real fancy and the seven pin socket a lot of times you can even buy them online cheaper depending on who you want to support.

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