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Gdetrailer

PA

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Joined: 01/05/2007

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Posted: 05/29/22 03:11pm Link  |  Quote  |  Print  |  Notify Moderator

jkwilson wrote:

How do you know the controller isn’t activating the brakes? Did you use a compass or listen for the hum at the wheels?


DC does not "hum", "buzz", "sing" or play any tune, you will not hear a thing.

Newer brake controllers while they do employ PWM to control the braking output operates at a very reduced output when you are sitting still. Even the manual lever output is reduced and does not apply full braking voltage when sitting still.

Even on older brake controllers, I never had any luck getting a compass to give a decent repeatable indication. There is a huge chunk of iron (drum) between the magnet and your compass. That drum absorbs and redirects a lot of the magnetic fields generated by the electro magnet and by the time it gets to your compass is very, very weak.

What I have found as 100% reliable way to trouble shoot is to jack up one side at a time and roll the wheels by hand and pull the break away pin. Wheels must stop as soon as the pin is pulled.

The breakaway system is supposed to apply full battery voltage from the trailer battery to the trailer brake magnets, if the breakaway system isn't working, then very good chance your truck system isn't going to make the brakes work either (IE trailer wiring problem)..

Put pin back in and you should now be able to roll the wheels by hand again. If they don't stop, then you need to access the wires behind each backing plate and verify that you have or don't have voltage with the breakaway pin pulled (note, the magnets are not going to melt either as per another Internet myth).

No voltage at backing plate then you have a break before the axles.

Voltage at the backing plate then you need to check the mechanicals behind the drum.

If you lift in the correct place, you can lift both wheels on the same side at a time.

Gdetrailer

PA

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Posted: 05/29/22 03:22pm Link  |  Quote  |  Print  |  Notify Moderator

prichardson wrote:

You need to confirm that you are getting brake voltage at the truck side of the 7 pin connector. If not the problem is in the truck not the trailer.


Old controllers of ages gone by could be tested that way.

NEW controllers, nope...

New controllers are "smart" controllers, they will not turn on the brake controller output unless is has a significant magnet load attached.

Newer brake controllers send a very short pulse of 12V every few seconds, that pulse is too short for most meters to read. Controller is checking to see if the pulse returns (echo or ring back). If controller does not see a echo or ring back or not enough echo or ring back it will not enable any output.

Typically need 1 or 2 brake magnets to trip the output on, incandescent bulbs or resistors may or may not work at all to fool the controller (I have tried that to build a test rig and incandescent bulbs or resistors would not fool any of my trucks with IBC).

2112

Texas

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Posted: 05/29/22 03:34pm Link  |  Quote  |  Print  |  Notify Moderator

jkwilson wrote:

How do you know the controller isn’t activating the brakes? Did you use a compass?........
I just busted this myth. Tried it with two functional magnetic compasses and two cell phones, one Samsung and the other is an iPhone. Pulled the emergency cable and no compass movement at all.

Now I need to go charge my battery back up.


2011 Ford F-150 EcoBoost SuperCab Max Tow, 2084# Payload, 11,300# Tow,
Timbrens, PullRite SuperGlide 2700 15K
2013 KZ Durango 2857


joebedford

Sheltering at home

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Posted: 05/29/22 03:50pm Link  |  Quote  |  Print  |  Notify Moderator

Just to throw a contrarian post into the mix, on my truck 2011 Chev, the pressure sensor on the master cylinder failed and the brake controller (factory) would not activate the trailer brakes in auto or manual. Brilliant design - I had to haul trailer to get repaired without any trailer brakes. SCARY. They had no reason to disable the manual control.

Grit dog

Black Diamond, WA

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Posted: 05/29/22 04:05pm Link  |  Quote  |  Print  |  Notify Moderator

Gdetrailer wrote:

Grit dog wrote:

To see if the trailer side is good, jump 12v to trailer side pin for the brakes. Should lock them up tight.
Your truck sounds fairly new. Is there a readout for trailer brake gain?


Don't have to "jump" anything, just pull the emergency breakaway pin then pull forward.. Break away system overrides the vehicles system (vehicle brake controller, wire and socket).

All wheels must lock and hold when break away system is activated.

Break away switch supplies full 12V from the trailers' on board battery.

If break away system does not lock any wheels then you must troubleshoot and diagnose the TRAILER electrical system and the mechanical part of the brakes behind the drums.

If break away locks all the wheels then consider changing the 7 pin connector and cable.

You have a 99% chance the trouble is not the vehicles fault but folks love to blame the vehicle for everything.. [emoticon]


Great tutorial but does nothin to diagnose a short in the trailer plug or pig tail, upstream of the breakaway system.


2016 Ram 2500, MotorOps.ca EFIlive tuned, 5” turbo back, 6" lift on 37s
2017 Heartland Torque T29

marpel

notapplicable

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Posted: 05/29/22 05:01pm Link  |  Quote  |  Print  |  Notify Moderator

Thanks very much for the continued replies and advice.

I just went through jacking the trailer and inspecting/regreasing etc, each wheel. I am comfortable with that stuff, but didn't consider checking the electricals. It was only when I hooked up the trailer to the truck (brand new '22), that I discovered no brakes. And as electricals is not my strong suit, I sought advice from the forum. And I am learning a lot, so thanks for that.

I think next step will be, as others have advised, activate the breakaway system. Then go from there.

Having said that, My grand-daughter is about to arrive for a couple week visit and she demands my full attention, so the brakes will have to wait a bit. As we are driving her back home (BC to Denver) with the trailer, I will have to figure this stuff out prior to heading out.

Thanks again for all your help,

Marv

Grit dog

Black Diamond, WA

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Posted: 05/29/22 05:52pm Link  |  Quote  |  Print  |  Notify Moderator

You didn’t say if the brakes worked previously recently with another truck or ?

jkwilson

Indiana

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Posted: 05/29/22 08:31pm Link  |  Quote  |  Print  |  Notify Moderator

Gdetrailer wrote:

jkwilson wrote:

How do you know the controller isn’t activating the brakes? Did you use a compass or listen for the hum at the wheels?


DC does not "hum", "buzz", "sing" or play any tune, you will not hear a thing.

Newer brake controllers while they do employ PWM to control the braking output operates at a very reduced output when you are sitting still. Even the manual lever output is reduced and does not apply full braking voltage when sitting still.

Even on older brake controllers, I never had any luck getting a compass to give a decent repeatable indication. There is a huge chunk of iron (drum) between the magnet and your compass. That drum absorbs and redirects a lot of the magnetic fields generated by the electro magnet and by the time it gets to your compass is very, very weak.

What I have found as 100% reliable way to trouble shoot is to jack up one side at a time and roll the wheels by hand and pull the break away pin. Wheels must stop as soon as the pin is pulled.

The breakaway system is supposed to apply full battery voltage from the trailer battery to the trailer brake magnets, if the breakaway system isn't working, then very good chance your truck system isn't going to make the brakes work either (IE trailer wiring problem)..

Put pin back in and you should now be able to roll the wheels by hand again. If they don't stop, then you need to access the wires behind each backing plate and verify that you have or don't have voltage with the breakaway pin pulled (note, the magnets are not going to melt either as per another Internet myth).

No voltage at backing plate then you have a break before the axles.

Voltage at the backing plate then you need to check the mechanicals behind the drum.

If you lift in the correct place, you can lift both wheels on the same side at a time.


Turn your flashers on with brake gain high. You’ll hear the magnets.


John & Kathy
2014 Grand Design Reflection 303RLS
2014 F250 SBCC 6.2L 3.73

Gdetrailer

PA

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Joined: 01/05/2007

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Posted: 05/29/22 09:34pm Link  |  Quote  |  Print  |  Notify Moderator

jkwilson wrote:

Gdetrailer wrote:

jkwilson wrote:

How do you know the controller isn’t activating the brakes? Did you use a compass or listen for the hum at the wheels?


DC does not "hum", "buzz", "sing" or play any tune, you will not hear a thing.

Newer brake controllers while they do employ PWM to control the braking output operates at a very reduced output when you are sitting still. Even the manual lever output is reduced and does not apply full braking voltage when sitting still.

Even on older brake controllers, I never had any luck getting a compass to give a decent repeatable indication. There is a huge chunk of iron (drum) between the magnet and your compass. That drum absorbs and redirects a lot of the magnetic fields generated by the electro magnet and by the time it gets to your compass is very, very weak.

What I have found as 100% reliable way to trouble shoot is to jack up one side at a time and roll the wheels by hand and pull the break away pin. Wheels must stop as soon as the pin is pulled.

The breakaway system is supposed to apply full battery voltage from the trailer battery to the trailer brake magnets, if the breakaway system isn't working, then very good chance your truck system isn't going to make the brakes work either (IE trailer wiring problem)..

Put pin back in and you should now be able to roll the wheels by hand again. If they don't stop, then you need to access the wires behind each backing plate and verify that you have or don't have voltage with the breakaway pin pulled (note, the magnets are not going to melt either as per another Internet myth).

No voltage at backing plate then you have a break before the axles.

Voltage at the backing plate then you need to check the mechanicals behind the drum.

If you lift in the correct place, you can lift both wheels on the same side at a time.


Turn your flashers on with brake gain high. You’ll hear the magnets.


I have a 2013, 2019 and 2020 F250s, that does not happen.

Your flashers have zero to do with the IBC brake controller on Fords, you can turn up the gain to the max on the Ford IBC and while you are sitting still the controller will reduce the output even using the manual control. The flashers will not override the brake controller. The reason for that is when you are still, there is zero reason to apply full braking voltage.

Perhaps maybe if you turned on your windshield wipers and hummed "I love a rainy night" perhaps the brakes might hum with you?

Ford IBC folds back the braking output according to speed and that includes the use of the manual over ride.

It is done for your safety so you do not accidentally over apply electric brakes manually while driving at low speeds.

DC does not make a sound and even with the newer IBC controllers which use PWM to control the output any noise possibly made will be "solo" (so low you can't hear it).. The PWM is done typically at a high frequency which will be above human hearing range (young adult hearing range tops out at 20Khz, PWM typically will be above 20Khz).

jkwilson

Indiana

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Joined: 06/14/2010

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Posted: 05/30/22 09:03am Link  |  Quote  |  Print  |  Notify Moderator

Gdetrailer wrote:

jkwilson wrote:

Gdetrailer wrote:

jkwilson wrote:

How do you know the controller isn’t activating the brakes? Did you use a compass or listen for the hum at the wheels?


DC does not "hum", "buzz", "sing" or play any tune, you will not hear a thing.

Newer brake controllers while they do employ PWM to control the braking output operates at a very reduced output when you are sitting still. Even the manual lever output is reduced and does not apply full braking voltage when sitting still.

Even on older brake controllers, I never had any luck getting a compass to give a decent repeatable indication. There is a huge chunk of iron (drum) between the magnet and your compass. That drum absorbs and redirects a lot of the magnetic fields generated by the electro magnet and by the time it gets to your compass is very, very weak.

What I have found as 100% reliable way to trouble shoot is to jack up one side at a time and roll the wheels by hand and pull the break away pin. Wheels must stop as soon as the pin is pulled.

The breakaway system is supposed to apply full battery voltage from the trailer battery to the trailer brake magnets, if the breakaway system isn't working, then very good chance your truck system isn't going to make the brakes work either (IE trailer wiring problem)..

Put pin back in and you should now be able to roll the wheels by hand again. If they don't stop, then you need to access the wires behind each backing plate and verify that you have or don't have voltage with the breakaway pin pulled (note, the magnets are not going to melt either as per another Internet myth).

No voltage at backing plate then you have a break before the axles.

Voltage at the backing plate then you need to check the mechanicals behind the drum.

If you lift in the correct place, you can lift both wheels on the same side at a time.


Turn your flashers on with brake gain high. You’ll hear the magnets.


I have a 2013, 2019 and 2020 F250s, that does not happen.

Your flashers have zero to do with the IBC brake controller on Fords, you can turn up the gain to the max on the Ford IBC and while you are sitting still the controller will reduce the output even using the manual control. The flashers will not override the brake controller. The reason for that is when you are still, there is zero reason to apply full braking voltage.

Perhaps maybe if you turned on your windshield wipers and hummed "I love a rainy night" perhaps the brakes might hum with you?

Ford IBC folds back the braking output according to speed and that includes the use of the manual over ride.

It is done for your safety so you do not accidentally over apply electric brakes manually while driving at low speeds.

DC does not make a sound and even with the newer IBC controllers which use PWM to control the output any noise possibly made will be "solo" (so low you can't hear it).. The PWM is done typically at a high frequency which will be above human hearing range (young adult hearing range tops out at 20Khz, PWM typically will be above 20Khz).


Trailer brake magnets make a very distinctive sound when the brakes are applied. You are 100% wrong. It’s loud enough to hear it standing near a parked trailer. If you’d care to bet on it, I’d be in for any amount you want to lose.

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