Thread Tools Search this Thread Display Modes
Old 11-07-2003, 10:20 PM   #1
3 Rivet Member
dinoburb's Avatar
1982 34' Limited
Tidewater , Virginia
Join Date: Dec 2002
Posts: 186
Intermittant Brakes

Hi Gang,

I have run into a problem that is new to me and that has been going on for some time, albiet without my knowledge until recently. I have upgraded my brake controller to a Prodigy and now I have discovered that I have intermittant brakes!

When I hook up the trailer the controller reports 'c' = connected. Pressing on the brake pedal I can adjust the amperage to the brakes per the instructions. The nice thing about the Prodigy is that it reports the amperage with each brake application, indicating the max amps applied during the stop or slow down event. However, it also indicates when there is a lost or no connection with an 'nc' in the indicator window. I see the 'nc' indication far too often. I can sit with the trailer hooked up and the truck off and the light will change from 'c' to 'nc' and back seemingly at will (who's Will?) (sorry can't help it!) While driving if the brakes are applied while the unit is in a state of connection it will stay connected and report the amperage being applied throughout the stop. However, the next application of the brakes the unit may be in a disconnected state and no power is being sent to the trailer's brakes.

I have rebuilt the trailer connector ( the one mounted on the trailer) by replacing the socket assy and trimming all wires back to bright copper. 25 year old wire ends, exposed to the atmosphere, tend to become brittle. That's been taken care of. The connector cord went through the same process: new connector plugs and trimmed wires. The truck socket has been replaced as well. All connections seem to be making good contact.

All lights on the trailer work all of the time (running, brake and turn). Battery recharges fully while driving.

If only one brake magnet wire were to break would the controller still 'see' the others and consider itself connected. The brake magnets are connected in parallel, I believe, so that should be the case.

Why do I have this phantom disconnect? It sure is good the 3/4 ton Suburban brakes are in good working order and designed to haul down such a large load. Now that I know what I'm looking for I can tell when the brakes are or are not working. Before, it was simply an uncomfortable feeling when the brakes were applied as some times the truck stopped much easier than other times.

Any help would be appreciated.

Take care,

Old trucks and old trailers . . . a comfortable combination!
AIR 1446
A-6E All Weather Attack Driver, BUFF
USN Aircraft Maintenance Officer, Ret.
'91 Suburban R-2500 w/BBC
'78 Honda GL-1000
'72 Triumph T-100R Daytona
dinoburb is offline   Reply With Quote
Old 11-07-2003, 10:26 PM   #2
uwe's Avatar
1963 26' Overlander
1958 22' Flying Cloud
1963 19' Globetrotter
Portola Hills , California
Join Date: Jun 2002
Location: 1963 26' Overlander
Posts: 4,764
Images: 41
Send a message via Skype™ to uwe
Take your wheels and hubs off and physically check all the connections inside the brake assembly. i had 3 of them disconnected on my old axles once...imagine the improvement once all the wires were connected...
I had a Tekonsha Voyager brake controller back then, it did not monitor the connectivity.
Also, look for corrosion on all the pertinent splices. A lot of work, but worth every minute, for your safety.

uwe is offline   Reply With Quote
Old 11-11-2003, 07:54 PM   #3
1 Rivet Member
Join Date: Mar 2003
Posts: 11
My 72 Excella did the same thing to me when I was pulling it through the Virginia mountains. What I found was I had a short to ground just in front of the forward axle under the belly skin. The wires had dropped down and chaffed on the skin. You are correct the brakes are wired in parallel. You are going to have to hunt it down. If you had one magnet broken it should not matter. You have a wire broken or bad connection between your plug and the axles. Depending on how handy you are with a multimeter you will find it. Another idea is to have someone step on the brakes and watch your controler while you start shaking down the wirs harness. Hope this helps.
72 Excella500 is offline   Reply With Quote
Old 11-12-2003, 07:22 AM   #4
Rivet Master
Commercial Member
rluhr's Avatar
1968 17' Caravel
2005 30' Safari
Somewhere , roaming America
Join Date: Apr 2003
Posts: 1,090
Images: 39
I have the exact same problem!

On my rig, the trailer is so lightweight that I haven't been able to determine if the brakes are in fact still operating when it is blinking "NC". Early on, I suspected that the brakes were working and that I just had a bad unit. It feels about the same when braking, and since it blinks "NC" so intermittently (1-10 seconds at a time) I usually don't have time to test carefully before the display changes back to "C".

A trip to the local dealer ended up with the theory that the 7-way connector cable was stiff with age, and pulling slightly out during travel. Solution recommended was a $48 extension cable. It seemed to work for a couple of days, but then the problem returned -- intermittently.

Now I'm leaning toward the "bad wiring" theory. We tried the easy stuff: having somebody shake and twist the connector wire while another person looked at the display -- no luck. The truck connector is new and all the contacts look perfect.

Next step is the multimeter. But that's just diagnosing the inevitable. I expect to drop the necessary belly skins and just rewire the whole darned thing. Unfortunately, that will have to wait until next spring because I don't have a garage to work in this winter.

I wonder how many people who have other brands of brake controllers have this issue and don't know it?

- RL
rluhr is offline   Reply With Quote
Old 11-12-2003, 08:00 AM   #5
Rivet Master
Happycampers's Avatar
1979 30' Argosy
Havelock , where we park it
Join Date: Jun 2003
Posts: 1,651
I had the same problem on my sob and the insulation had rubbed off the wire by the axel and would ground out and no brake then it would move off it from the shift of the trailer and back and forth. Had to rewire the whole brake system, that is when I found it. Marvin
Marvin & Annie
Niki (fur baby)
1979 Argosy 30 (Costalotta)
WBCCI 10103
"Happiness is a warm Puppy" Charles Schulz
Happycampers is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
What is your Brake Controller of Choice? overlander64 Brakes & Brake Controllers 71 11-29-2008 08:40 AM
Some towing Q & A for newbies femuse Towing, Tow Vehicles & Hitches 3 08-24-2004 08:05 AM
Grabbing Brakes 74Tradewind Brakes & Brake Controllers 15 08-05-2004 05:26 PM
Trailer brakes won't lock-up? John Brakes & Brake Controllers 24 02-06-2003 12:22 PM
Heeeelp! My brakes have failed...anyone have a similar experience? williamhenshall Airstream Motorhome Forums 9 07-12-2002 03:04 PM

Virginia Campgrounds

Reviews provided by

Our Communities

Our communities encompass many different hobbies and interests, but each one is built on friendly, intelligent membership.

» More about our Communities

Automotive Communities

Our Automotive communities encompass many different makes and models. From U.S. domestics to European Saloons.

» More about our Automotive Communities

Marine Communities

Our Marine websites focus on Cruising and Sailing Vessels, including forums and the largest cruising Wiki project on the web today.

» More about our Marine Communities

Copyright 2002-2015 Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 06:40 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.