Travel Trailer woes

[Yota Up]

It is the P3 controller that I have, and I love the slider exactly for what you stated.

Ok, checked the blue output on my connector. No test light so used multimeter with one lead on ground pin and one at trailer brakes pin..
When using the slider I get full 12 volts. When pushing the brake pedal I get 3 volts(that's due to the inertia system of the brake controller).

So if my truck is throwing good but trailer won't work, how in the world would someone else's truck make the trailer work?
I can't wrap my head around that.

 

[Provience]

It is the P3 controller that I have, and I love the slider exactly for what you stated.

Ok, checked the blue output on my connector. No test light so used multimeter with one lead on ground pin and one at trailer brakes pin..
When using the slider I get full 12 volts. When pushing the brake pedal I get 3 volts(that's due to the inertia system of the brake controller).

So if my truck is throwing good but trailer won't work, how in the world would someone else's truck make the trailer work?
I can't wrap my head around that.

Is the other truck the same weight as yours? It may well simply feel like it isn't working because of the weight difference, regardless of "rating" and such.

Since you have verified that your plug side is correct, go measure at the brake itself and see if you are getting the same reading back there

 

[DMG]

It is the P3 controller that I have, and I love the slider exactly for what you stated.

Ok, checked the blue output on my connector. No test light so used multimeter with one lead on ground pin and one at trailer brakes pin..
When using the slider I get full 12 volts. When pushing the brake pedal I get 3 volts(that's due to the inertia system of the brake controller).

So if my truck is throwing good but trailer won't work, how in the world would someone else's truck make the trailer work?
I can't wrap my head around that.

With a car battery or jump pack and jumper wires, jumper the corresponding pin on the trailer and see if it locks up the brakes. If it doesnt, keep trying pins until the brakes lock up. Use jumper cabl3s or something to ensure a ground between the battery and the trailer chassis

You may need to find a trailer with surge brakes.

 

[Yota Up]

Is the other truck the same weight as yours? It may well simply feel like it isn't working because of the weight difference, regardless of "rating" and such.

Since you have verified that your plug side is correct, go measure at the brake itself and see if you are getting the same reading back there

No, other = bigger. And it has nothing to do with feel because I get zero even when pushing slider all the way.

D Nelly, I have the lowest boost setting on so like you said it's gentle at first and the inertia system increases the voltage based on weight transfer.
The brakes do not work at all on that TT even if I hit the slider manually all the way. Zero braking happens.

It's like the controller doesn't allow anything to happen once that error pops up. Trailer lights and blinkers and brake lights still work, though.

 

[MuntCuffin]

That makes a big difference sometimes. Still cant see how a shop is working for under $125 labor

I wouldn't put a socket on a bolt for less than $100/hr.

Way too many people out there that have no idea or no desire to work on stuff.

That means if you know how or are willing to work on stuff, your time is valuable. Much more so than white collar frank.

 

[Provience]

No, other = bigger. And it has nothing to do with feel because I get zero even when pushing slider all the way.

D Nelly, I have the lowest boost setting on so like you said it's gentle at first and the inertia system increases the voltage based on weight transfer.
The brakes do not work at all on that TT even if I hit the slider manually all the way. Zero braking happens.

It's like the controller doesn't allow anything to happen once that error pops up. Trailer lights and blinkers and brake lights still work, though.

Zero braking or zero voltage at the brakes? If you've got volts at the plug, just keep following the wire back and see where it drops off.

You should be at boost 2 or 3 or whatever is higher. Your trailer is as heavy or heavier than your truck

 

[Yota Up]

Zero braking. I suspect my controller stops or prevents sending brake signal the moment it detects open ground.
It would make sense if my controller is more sensitive than others. That would be a good explanation for why theirs work and mine doesn't.
If so, the question becomes is it a defective controller that should be replaced with same model or time to buy a different model.

 

[Provience]

Zero braking. I suspect my controller stops or prevents sending brake signal the moment it detects open ground.
It would make sense if my controller is more sensitive than others. That would be a good explanation for why theirs work and mine doesn't.
If so, the question becomes is it a defective controller that should be replaced with same model or time to buy a different model.

They do die from time to time.

 

[Chevy_man]

Zero braking. I suspect my controller stops or prevents sending brake signal the moment it detects open ground.
It would make sense if my controller is more sensitive than others. That would be a good explanation for why theirs work and mine doesn't.
If so, the question becomes is it a defective controller that should be replaced with same model or time to buy a different model.

Replace any plugs with corrosion. Mine will go screwy and turn off and on with a corroded plug. Don't know how many borrowed trailers I've brought back with new plugs on them.


Push the + button and crank the gain to 12, turn the boost on 3.
When someone pushes the brake pedal, your meter should see 12v+, and it'll then back off slightly as he boost backs off. A multimeter creates a very high resistive load when measuring voltage so the controller will think it sees brakes.

The gyro will increase gain with motion, but by manually turning it 100% up you're essentially bypassing it.

I'll have my 00 back next weekend and I can verify the working voltages you should see.


It honestly sounds like you have 2 issues. 1 is you have the gain turned down way too low, and 2 is corrosion and intermittent connection.


Also, have you verified the brakes are adjusted? If they get too far out it takes a bit more voltage to get them started as it has to pull the shoes a lot farther. I can go up and down 2-3 points on the controller with the exact same trailer as the brakes wear and I readjust them.

 

[CarterKraft]

You ran new wires from controller to 7 pin on bumper? What size wires? Brake + straight from blue on controller to receptacle on bumper, no splices or connections?

The ground for the 7 pin, where from? What size? Any splices?

In reality you could redo the entire trailer/truck wiring in a afternoon good enough to get you going for this summer.

 

[rockota]

You ran new wires from controller to 7 pin on bumper? What size wires? Brake + straight from blue on controller to receptacle on bumper, no splices or connections?

The ground for the 7 pin, where from? What size? Any splices?

In reality you could redo the entire trailer/truck wiring in a afternoon good enough to get you going for this summer.

This.

And there is a difference in wiring between a. 7-pin and an RV 7-pin.

 

[Gravy]

Home run the trailer brakes.

Run a new wire directly from the trailer brakes to the plug in. Bypass the existing wiring.

Find a gravel driveway, hold the pinch thing, and drive forward. You should feel/hear dragging.

Does the popup even have brakes?

 

[Gravy]

Also, I know you're here seeking advise but sometimes you have to fight these sombitchin problems.

 

[JunkCJ6]

Zero braking. I suspect my controller stops or prevents sending brake signal the moment it detects open ground.
It would make sense if my controller is more sensitive than others. That would be a good explanation for why theirs work and mine doesn't.
If so, the question becomes is it a defective controller that should be replaced with same model or time to buy a different model.

If you suspect the controller may be bad, call teknosha support, they are excellent. The tab on the gain wheel on my p2 broke, called to order a new gain wheel. Got an rma number for tekonsha to repair, brand new one was in my mailbox 3 days later. Was well outside the warranty period and no proof of purchase needed.

 

[Yota Up]

You ran new wires from controller to 7 pin on bumper? What size wires? Brake + straight from blue on controller to receptacle on bumper, no splices or connections?

The ground for the 7 pin, where from? What size? Any splices?

In reality you could redo the entire trailer/truck wiring in a afternoon good enough to get you going for this summer.

I used this(RV 7 pin, not ag):

Same size wire as you see there, I think 14 or 16. The ground pin, as you see, is right there and that is grounded to an existing bracket bolt inside the bumper(which shows no ohms when touched to negative terminal).
The only splices were the blue wire and black wire with those yellow splices that came with the kit. I grabbed the signal wire from the wire that goes to the brake light.

Yes, the pop up had brakes. I could push the slider and never touch my truck brakes and the camper could bring me to a stop. I could hook it up right now and do it again.

Gonna call Teknosha on Monday. Hopefully they'll send me another unit and check this one out.

 

[Gravy]

Also also, remove the drums and push the magnet lever arm by hand. It should move freely and push the shoes out.

My experience with trailers sitting in swampy or salty areas the lever pivot point gets rusty and prevents the lever from moving and/or causes the brakes to stick on.

Additionaly, unplugg your car battery and go to town with a wire brush on both the vehicle sockets, plugs, and trailer plugs. Hose them down with brake cleaner, like a whole can.

Sorry to hear this is holding up family fun, but try throwing the kitchen sink at it.

 

[Chevy_man]

I used this(RV 7 pin, not ag):

Same size wire as you see there, I think 14 or 16. The ground pin, as you see, is right there and that is grounded to an existing bracket bolt inside the bumper(which shows no ohms when touched to negative terminal).
The only splices were the blue wire and black wire with those yellow splices that came with the kit. I grabbed the signal wire from the wire that goes to the brake light.

Yes, the pop up had brakes. I could push the slider and never touch my truck brakes and the camper could bring me to a stop. I could hook it up right now and do it again.

Gonna call Teknosha on Monday. Hopefully they'll send me another unit and check this one out.

Signal wire from the brake light? There's a brake switch right at the pedal under the dash within 12" of the controller

I just stripped some insulation off the brake switch wire with a knife, wrapped the controller wire around it, soldered it together, and wrapped it in super 88.

 

[CarterKraft]

I used this(RV 7 pin, not ag):

Same size wire as you see there, I think 14 or 16. The ground pin, as you see, is right there and that is grounded to an existing bracket bolt inside the bumper(which shows no ohms when touched to negative terminal).
The only splices were the blue wire and black wire with those yellow splices that came with the kit. I grabbed the signal wire from the wire that goes to the brake light.

Yes, the pop up had brakes. I could push the slider and never touch my truck brakes and the camper could bring me to a stop. I could hook it up right now and do it again.

Gonna call Teknosha on Monday. Hopefully they'll send me another unit and check this one out.

If it's 4 axles 14/16 ga is going to limit your breaking ability, you need to carry the amps from the controller to the axles, the entire length of the truck wire and trailer wire. (I don't think this is your ultimate problem but let's not forget about it)

What error do you get on the controller? If the controller detects a problem it's likely nothing is going to be sent out the controller, manually or via inertia.

To reiterate on the ground (no ohms) you are saying that the meter reads 0.0 ohms correct?
There is a better test if you can do it.
Put one lead of your meter on the negative post of the battery and the other lead on the farthest point in the brake circuit negative, at the magnet connection would be perfect. (You will have to use a extension of wire for the meter lead to be able to reach the battery that is fine.)
With all the trailer running lights on apply the brakes manually and read the DVOM, you should be getting less than .5 of a DC volt. With that same setup move the probe at the magnet connection to the positive and record the voltage.

If the controller is fubar this may be all for naught.

 

[CarterKraft]

Signal wire from the brake light? There's a brake switch right at the pedal under the dash within 12" of the controller

I just stripped some insulation off the brake switch wire with a knife, wrapped the controller wire around it, soldered it together, and wrapped it in super 88.

Good point.

Yota Up
Did you run the brake signal wire from the back to the controller? Are you sure that is behaving as it should?
I think normally we would source it from the brake pedal switch as was said above.

 

[Thefishguy77]

I need a forum for camper trailers that has a lot of traffic and activity to be able to ask questions and solicit advice on making repairs and upgrades on a travel trailer.
My other thread here is about a distribution hitch, but honestly having no brakes is killing this entire summer for my kids because we can't go anywhere good until it's fixed.
I'm at my wits end and furious at this point.

Background:
My truck + TT = "open ground, no brakes".
My truck + pop up trailer = brakes all good.
Other person's truck + TT = brakes all good.

What in the world could explain that?
Not sure you guys can help me with it, and I think I've done everything I can possibly do at this point so hoping a dedicated trailer forum might let me look at one or two more things.
And I'm sure things will come up in the future so might as well sign up to another place to bother those folks with my stupid questions.
Thanks.

Replace your 7pin connector on your truck. Mine was intermittent on my truck and I chased bullshit electrical on 2 different trailers when the trailer worked fine on others rig and my boat trailer was fine on my rig. Threw a $15? Replacement plug on my truck and problem solved.

 

[Thefishguy77]

50 to 100 an hour for trailer work?

anybody anywhere for almost anything starts at 125 an hour and the go up from there.
I recently bought a diesel pusher.
Hourly fees from 175 to 225 depending on what system you need to have work done on. (But 225 an Hour in Hobbs New Mexico at the Cummins shop got me back on the road in an hour and a half instead f who knows how long)

Trailer brakes.
Someone else posted, power the brakes up on the trailer directly from a battery. You should be able to hear them click.
Work toward the drums until you get them to operate.
This will help to locate where in the wiring the break is.

I know a 12v electrical savant up in the Bellevue Washington area. Thats not convenient but those guys are out there. I have had to use him a few times. Was like 75/hr. Well worth it.

 

[DMG]

This.

And there is a difference in wiring between a. 7-pin and an RV 7-pin.

Dont confuse him further. The difference is just the color of wires. The pin location is the same.

 

[Clb]

Have someone move the slider on your brake controller while you put a test light on the blue wire. If it works, have them try it with the brake pedal.

If you jumper #4 to #2 you get power into the drums...

3/4 gets ya party lights also.

 

[Gbkeith]

Plug on trailer has been replaced carefully. Was hoping that was it but still same problem.

I'd love to hear any guesses on how this could be. Other truck can work brakes but I can't. Yet I can work brakes on different trailer.

Fix the plug on your truck. Check the four factory wires and the three you added.

 

[Stingray]

If we can't fix your brake problem a RV forum won't do much better.

Brakes are simple as fuck, power and ground....
Apply brakes manually (may need helper)
Measure voltage at brake magnet wires.
Ideally check current of said magnets, each or all together.

In the other thread I couldn't keep up for all the different shit.

I was going to suggest testing the brakes 100% independent from the truck. Apply power and ground to see if they work, eliminate as many connections as possible.
like crawl under the trailer with a battery and test.

an M12 battery will work.

 

[DMG]

I was going to suggest testing the brakes 100% independent from the truck. Apply power and ground to see if they work, eliminate as many connections as possible.
like crawl under the trailer with a battery and test.

an M12 battery will work.

That has been suggested.

 

[DMG]

With a car battery or jump pack and jumper wires, jumper the corresponding pin on the trailer and see if it locks up the brakes. If it doesnt, keep trying pins until the brakes lock up. Use jumper cabl3s or something to ensure a ground between the battery and the trailer chassis

You may need to find a trailer with surge brakes.

Did you try this?

 

[Yota Up]

Signal wire from the brake light? There's a brake switch right at the pedal under the dash within 12" of the controller

I just stripped some insulation off the brake switch wire with a knife, wrapped the controller wire around it, soldered it together, and wrapped it in super 88.

The signal wire connects to the plug at the rear bumper, so best source is brake light for short run.
The other wire is the blue from the controller at the dash, that wire is a long run to the rear bumper to the connector.

Did you try this?

Not yet. I'm going to have my neighbor hook up his truck to my TT so I can see it for myself. I'm also going to ask him if I can plug my truck into his travel trailer and I think that will tell us where the problem is and then go from there.

 

[Chevy_man]

The signal wire connects to the plug at the rear bumper, so best source is brake light for short run.
The other wire is the blue from the controller at the dash, that wire is a long run to the rear bumper to the connector.

Not yet. I'm going to have my neighbor hook up his truck to my TT so I can see it for myself. I'm also going to ask him if I can plug my truck into his travel trailer and I think that will tell us where the problem is and then go from there.

Brake controller should have 4 wires. Ground, power, brake switch, brake power out. Brake controller has power from a fused source, when it sees the brake signal wire power up it applies power to the output according to where the gain is set.

Trailer plug should be 6. Ground, aux power +12v (fused at 20-30A), left turn, right turn, running lights, and trailer brake. Reverse is the 7th but rarely do trailers have reverse lighting.

So for trailer lights your left and right turn also double as brake lights. This is why it makes zero sense that you tapped into the brake lights for anything.

The factory 4 pin should have been: ground, left turn, right turn, and running lights.

You should have only needed to add trailer brake wire from the controller, and aux 12v fused from an ignition switched source in the fuse box.




This may be explaining it all right here

 

[IowaOffRoad]

Brake controller should have 4 wires. Ground, power, brake switch, brake power out. Brake controller has power from a fused source, when it sees the brake signal wire power up it applies power to the output according to where the gain is set.

Trailer plug should be 6. Ground, aux power +12v (fused at 20-30A), left turn, right turn, running lights, and trailer brake. Reverse is the 7th but rarely do trailers have reverse lighting.

So for trailer lights your left and right turn also double as brake lights. This is why it makes zero sense that you tapped into the brake lights for anything.

The factory 4 pin should have been: ground, left turn, right turn, and running lights.

You should have only needed to add trailer brake wire from the controller, and aux 12v fused from an ignition switched source in the fuse box.




This may be explaining it all right here

The only thing I can think of is you need a tail light converter for most Japanese vehicle as they have separate brake and turn signals. If OP hasn’t converted his tail lights, that may also be a problem.