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-   -   Wiring help wanted. (https://www.seccs.org/forums/showthread.php?t=6706)

wrxkidid 2008-03-18 10:16 PM

Wiring help wanted.
 
Hey guys. Well I better not get shit for this but i guess its the complete wrong forum :lol: I need a break controller for my truck to tow our trailer. I was looking at the Tekonsha Priumus because it uses the same software as the Tekonsha Prodigy (which is meant for up to 3 axles instead of 4 so it is a little pricier but I wont be towing something that big with my truck and is praised as one of the best) and I don't want to go cheap on something that can be life threatening if it fails Any other suggestions on controllers though. I guess this would be more a question for Scott since he is the only person I know who tows stuff on the forum, and I guess Matt too.

My truck has a 4 pin flat so I need an adapter. The adapter plugs into the existing harness but also has 3 other wires. One being a ground, the other for the controller but I am absolutely lost on what the other could be. 12v hot maybe?

This is the wiring diagram I am looking at, http://www.marksrv.com/wiring.htm

but the colors on the adapter I am looking at do not match up. I want to do this myself but I am horrible with wiring, How simple of a job does this sound like or should I just roll over and pay someone, or better yet one of you smart engineer types want to help me and I will pay you?

Here is the adapter I am looking at, it is the first one 4 way flat to 7 way flat pin short wire.
http://bageco.com/adapter.htm

bxracer69 2008-03-18 11:40 PM

I'll have Liz weigh in on this later, she tows her 4 horse slant w/tack room all over the place and has done a ton of research into trailer brake stuff. I know she had hers installed and it wasn't too pricey.

Dean 2008-03-19 08:12 AM

4 wire will not run brakes, you need a new harness for the brake unit.

What are you planning to pull? Isn't that a 4 cylinder?

Small trailers even up to a twin Jetski trailer do not have/need brakes if the truck has good brakes.

All the brake units are very reliable. They have to be from a liability perspective. I did a lot of research when I got mine, and the bottom line is unless your truck has an integrated towing package tied to the brake system, they are all basically the same. A pendulum and a gain control. Yes, there are snazzy electronic adaptive ones, but I'm not convinced they are worth the premium. (Even the cheap ones don't use pendulums any more by the way.)

Physics works pretty well. You don't need a fancy accelerometer and a LED display to apply brakes on a trailer.

Oh, and the number of wheels on the trailer does not mean how many brakes it has. even some triple axles only have 1 pair of brakes. Almost all dual axles only have 1 pair, so a 2/4 is fine.

I can look and see what is in the truck later.

I wouldn't pay over $100 and would tend toward $50-75.

Oh, and if you are thinking of a boat, they don't use electric brakes typically. They use hydraulic on the hitch. No controller / wiring required.

sperry 2008-03-19 09:32 AM

What Dean said, the 4-pin connectors are for lights only. You'll want a 6 or 7-pin round connector if you're going to be rewiring things.

Check this out: http://www.etrailer.com/faq_wiring.aspx

As far as a controller, I have the Tekonsha Voyager (it was on the truck when I bought it). It's a generation older than the Prodigy, but it seems to work pretty good. If I was buying one new, I'd get the Primus or the Prodigy, but if you can get a Voyager second hand for cheap, it'll do everything you need.

On a side note, brake controllers are actually a lot like audio amplifiers. The input signal is the voltage from the accelerometer that tells the unit how hard the truck is braking. That signal needs to be amplified into voltage that physically clamps the brakes on the trailer. The manipulation of the signal is similar to a crossover and an amplifier. The crossover part adjusts how much input signal is needed to trigger an output to the brakes (though it's not a hard cut-off like a real crossover), and the amplifier part just sets the gain on the signal to allow you to adjust the amount of braking the trailer does to compensate for different load weights.

The newer controllers automatically adjust the "crossover" leaving you to play just with the gain. The older units (like my Voyager) have a knob for playing with the crossover (which is basically the aggressiveness of the unit). It's not really hard to use the older style units once you get a feeling for what the knobs do.

Dean 2008-03-19 09:50 AM

I have a Voyager, but don't believe the knobs are the same as yours. One knob on each side, a lever for manual braking and a single multicolor LED.

The left knob is to level the sensor and the right knob is gain. No input signal control crossover type function as far as I know.

Once it is installed, you should only have to play with the gain based on load and brake performance.

If the trailer brakes lock up or the trailer feels like it brakes first and pulls the truck back, gain is to high.

If it feels like the trailer is pushing the truck under braking, turn up the gain.

I make a couple test slows/stops every time I drive it. I've even been known to turn up the gain when empty to make sure both sides chirp/lock evenly. :)

sperry 2008-03-19 09:54 AM

Quote:

Originally Posted by Dean (Post 115887)
I have a Voyager, but don't believe the knobs are the same as yours. One knob on each side, a lever for manual braking and a single multicolor LED.

The left knob is to level the sensor and the right knob is gain. No input signal control crossover type function as far as I know.

Once it is installed, you should only have to play with the gain based on load and brake performance.

If the trailer brakes lock up or the trailer feels like it brakes first and pulls the truck back, gain is to high.

If it feels like the trailer is pushing the truck under braking, turn up the gain.

I make a couple test slows/stops every time I drive it. I've even been known to turn up the gain when empty to make sure both sides chirp/lock evenly. :)

Go re-read the instructions on that "level knob". It adjusts not just to compensate for the angle of the unit, but also for how aggressively it reacts to deceleration.

Dean 2008-03-19 10:02 AM

Quote:

Originally Posted by sperry (Post 115888)
Go re-read the instructions on that "level knob". It adjusts not just to compensate for the angle of the unit, but also for how aggressively it reacts to deceleration.

Agreed. If you tilt the sensor forward, the sensor is going to react sooner and vice a versa. I have never needed to change that knob after initial setup as I think it is a function of the responsiveness/performance of the braking system on the truck, not the trailer unless the different loading of the trailer changes the angle of the truck.

I think the new ones autolevel.

sperry 2008-03-19 10:31 AM

Quote:

Originally Posted by Dean (Post 115891)
Agreed. If you tilt the sensor forward, the sensor is going to react sooner and vice a versa. I have never needed to change that knob after initial setup as I think it is a function of the responsiveness/performance of the braking system on the truck, not the trailer unless the different loading of the trailer changes the angle of the truck.

I think the new ones autolevel.

I don't normally play with the level knob on my controller either.

However, I have noticed that I can fine tune the difference between light braking and hard braking with that knob. I've had things feeling good with a low setting on the level and a high gain while braking lightly, only to find that under hard braking there wasn't enough trailer brake. Adjusting the level knob more aggressively allows you to run less gain and have better overall brake performance across all types of braking conditions.

It's just something to play with until it feels "good".

wrxkidid 2008-03-19 01:39 PM

Dean my truck is a V6 and the frame is rated to tow 6500lbs with the motor so I am not worried about that. I don't think I will be towing anything even close to that heavy.

I am pretty sure the trailers brakes are electric, no hydraulic stuff that I saw. I know I need a 7 wire round, I am getting an adapter that uses the existing 4 flat and then provides the other wires that you just need to run.

SteveM 2008-03-19 02:16 PM

Quote:

Originally Posted by sperry (Post 115894)

It's just something to play with until it feels "good".

:huh:

Oh yeah? :lol:









Sorry, but couldn't pass that one up. :devil:

sperry 2008-03-19 02:25 PM

Quote:

Originally Posted by SteveM (Post 115913)
:huh:

Oh yeah? :lol:









Sorry, but couldn't pass that one up. :devil:

I guess someone had to hit that pitch.

Dean 2008-03-19 03:39 PM

Quote:

Originally Posted by wrxkidid (Post 115912)
Dean my truck is a V6 and the frame is rated to tow 6500lbs with the motor so I am not worried about that. I don't think I will be towing anything even close to that heavy.

I am pretty sure the trailers brakes are electric, no hydraulic stuff that I saw. I know I need a 7 wire round, I am getting an adapter that uses the existing 4 flat and then provides the other wires that you just need to run.

Check the shop manual for your truck (Or do some googleing). You may already have a 7 wire harness running through the truck, just not the plug on the end. My Furd did and I just plugged the controller into the cab and changed/added the jack at the back.

I'd suggest a mounted 7 wire jack and adapt back to 4 if you need it rather than the other way around. not sure what your setup looks like, but many hack job 4 wires hookups that just hang out of the chassis somewhere without a real mounted jack are trouble and the wire gauge is often not heavy enough for the amperage that brakes need.

sperry 2008-03-19 04:15 PM

Quote:

Originally Posted by Dean (Post 115924)
Check the shop manual for your truck (Or do some googleing). You may already have a 7 wire harness running through the truck, just not the plug on the end. My Furd did and I just plugged the controller into the cab and changed/added the jack at the back.

I'd suggest a mounted 7 wire jack and adapt back to 4 if you need it rather than the other way around. not sure what your setup looks like, but many hack job 4 wires hookups that just hang out of the chassis somewhere without a real mounted jack are trouble and the wire gauge is often not heavy enough for the amperage that brakes need.

Unlikely it will be pre-wired for brakes. Ideally, you should add a 7-wire in addition to the existing 4-wire, and not convert either way.

Joeyy 2008-03-19 04:16 PM

Are you towing the trailer with a kart in it?

wrxkidid 2008-03-19 05:59 PM

Nope quads. I didn't buy them my dad did.

No kart for me. Didn't make the money :/

Quote:

Originally Posted by sperry (Post 115929)
Unlikely it will be pre-wired for brakes. Ideally, you should add a 7-wire in addition to the existing 4-wire, and not convert either way.

Why is this? it seems like it would be much simpler to use the adapter and just wiring the truck for the brake portion of it than to rewire the entire truck.

100_Percent_Juice 2008-03-19 08:50 PM

Just use your grandma's power chair mount on the back of your moms car to tow your quad.

Dean 2008-03-19 11:50 PM

Quote:

Originally Posted by wrxkidid (Post 115937)
Nope quads. I didn't buy them my dad did.

No kart for me. Didn't make the money :/



Why is this? it seems like it would be much simpler to use the adapter and just wiring the truck for the brake portion of it than to rewire the entire truck.

Adapters fail for a number of reasons. If it is important enough to have brakes, it needs a mounted jack that matches the trailer's plug. It doesn't mean you rewire the whole truck, just the wiring at the back and a new pair for the brakes if not already present.

Why any truck manufacturer would't pre-wire for a brake controller and trailer I don't know. Ford and Chevy do. You just have to buy the plugs/adapters for the ends, I mean "tow package". :)

If you don't feel comfortable doing this wiring, take it to a shop.

sperry 2008-03-20 09:34 AM

Quote:

Originally Posted by Dean (Post 115947)
Adapters fail for a number of reasons. If it is important enough to have brakes, it needs a mounted jack that matches the trailer's plug. It doesn't mean you rewire the whole truck, just the wiring at the back and a new pair for the brakes if not already present.

Why any truck manufacturer would't pre-wire for a brake controller and trailer I don't know. Ford and Chevy do. You just have to buy the plugs/adapters for the ends, I mean "tow package". :)

If you don't feel comfortable doing this wiring, take it to a shop.

It's not likely to be prewired for brakes because it's already prewired for lights only. What are the chances that Toyota went through the process of running all the wires for brakes and lights, then only wired the lights to a 4-pin connector? Not likely, especially since the Tacoma is the smallest truck they make and has only a 6500 lb towing capacity. Most people that would tow with a Tacoma aren't going to be towing things larger than jetskis or a small Uhaul trailer... stuff that you don't need trailer brakes for.

Even the "small" 1500 Chevy and F-150 Ford trucks tow more like 10,000 lbs and come with a tow option that includes the 7-pin connectors, which is why they're pre-wired for lights and brakes.


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